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| author | Thomas Voss <mail@thomasvoss.com> | 2024-11-27 20:54:24 +0100 |
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| committer | Thomas Voss <mail@thomasvoss.com> | 2024-11-27 20:54:24 +0100 |
| commit | 4bfd864f10b68b71482b35c818559068ef8d5797 (patch) | |
| tree | e3989f47a7994642eb325063d46e8f08ffa681dc /doc/rfc/rfc1987.txt | |
| parent | ea76e11061bda059ae9f9ad130a9895cc85607db (diff) | |
doc: Add RFC documents
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| -rw-r--r-- | doc/rfc/rfc1987.txt | 2467 |
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diff --git a/doc/rfc/rfc1987.txt b/doc/rfc/rfc1987.txt new file mode 100644 index 0000000..1d58f38 --- /dev/null +++ b/doc/rfc/rfc1987.txt @@ -0,0 +1,2467 @@ + + + + + + +Network Working Group P. Newman, Ipsilon +Request for Comments: 1987 W. Edwards, Sprint +Category: Informational R. Hinden, Ipsilon + E. Hoffman, Ipsilon + F. Ching Liaw, Ipsilon + T. Lyon, Ipsilon + G. Minshall, Ipsilon + August 1996 + + + + Ipsilon's General Switch Management Protocol Specification + Version 1.1 + + + + + +Status of this Memo + + This memo provides information for the Internet community. This memo + does not specify an Internet standard of any kind. Distribution of + this memo is unlimited. + + +Abstract + + The General Switch Management Protocol (GSMP), is a general purpose + protocol to control an ATM switch. GSMP allows a controller to + establish and release connections across the switch; add and delete + leaves on a point-to-multipoint connection; manage switch ports; + request configuration information; and request statistics. + + + + + + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 1] + +RFC 1987 GSMP Protocol Specification August 1996 + + +Table of Contents + + 1. Introduction....................................................3 + + 2. GSMP Packet Format..............................................4 + + 3. Connection Management Messages..................................7 + 3.1 Add Branch Message.........................................11 + 3.2 Delete Branch Message......................................12 + 3.3 Delete Tree Message........................................13 + 3.4 Verify Tree Message........................................13 + 3.5 Delete All Message.........................................14 + 3.6 Move Branch Message........................................14 + + 4. Port Management Message........................................16 + + 5. Statistics Messages............................................20 + 5.1 VC Activity Message........................................20 + 5.2 Port and VC Statistics Messages............................23 + 5.2.1 Port Statistics Message..............................26 + 5.2.2 VC Statistics Message................................26 + + 6. Configuration..................................................26 + 6.1 Switch Configuration Message...............................27 + 6.2 Port Configuration Message.................................28 + 6.3 All Ports Configuration Message............................32 + + 7. Event Messages.................................................33 + 7.1 Port Up Message............................................35 + 7.2 Port Down Message..........................................35 + 7.3 Invalid VPI/VCI Message....................................35 + 7.4 New Port Message...........................................35 + 7.5 Dead Port Message..........................................36 + + 8. Adjacency Protocol.............................................36 + 8.1 Packet Format..............................................36 + 8.2 Procedure..................................................39 + + 9. Failure Response Messages......................................41 + + References........................................................43 + Security Considerations...........................................43 + Authors' Addresses................................................43 + + + + + + + + +Newman, et. al. Informational [Page 2] + +RFC 1987 GSMP Protocol Specification August 1996 + + +1. Introduction + + The General Switch Management Protocol (GSMP), is a general purpose + protocol to control an ATM switch. GSMP allows a controller to + establish and release connections across the switch; add and delete + leaves on a point-to-multipoint connection; manage switch ports; + request configuration information; and request statistics. It also + allows the switch to inform the controller of asynchronous events + such as a link going down. GSMP runs across an ATM link connecting + the controller to the switch, on a control connection (virtual + channel) established at initialization. The GSMP protocol is + asymmetric, the controller being the master and the switch being the + slave. Multiple switches may be controlled by a single controller + using multiple instantiations of the protocol over separate control + connections. + + A switch is assumed to contain multiple "ports". Each port is a + combination of one "input port" and one "output port". Some GSMP + requests refer to the port as a whole whereas other requests are + specific to the input port or the output port. ATM cells arrive at + the switch from an external communication link on incoming virtual + channels at an input port. ATM cells depart from the switch to an + external communication link on outgoing virtual channels from an + output port. Virtual channels on a port or link are referenced by + their virtual path and virtual channel identifiers (VPI/VCI). A + virtual channel connection across a switch is formed by connecting an + incoming virtual channel to one or more outgoing virtual channels. + Virtual channel connections are referenced by the input port on which + they arrive and the virtual path and virtual channel identifiers + (VPI/VCI) of their incoming virtual channel. + + In general a virtual channel is established with a certain quality of + service (QOS). Unfortunately this is an ill defined and changing + concept as new ideas make their way into hardware. For this version + of the GSMP protocol it is assumed that each virtual channel + connection may be assigned a priority when it is established. It may + be assumed that for virtual channel connections that share the same + output port, an ATM cell on a connection with a higher priority is + much more likely to exit the switch before an ATM cell on a + connection with a lower priority if they are both in the switch at + the same time. The number of priorities that each port of the switch + supports may be obtained from the port configuration message. + + Switch ports are described by a 32 bit port number. The switch + assigns port numbers and it may typically choose to structure the 32 + bits into sub-fields that have meaning to the physical structure of + the switch (e.g. shelf, slot, port). In general, a port in the same + physical location on the switch will always have the same port + + + +Newman, et. al. Informational [Page 3] + +RFC 1987 GSMP Protocol Specification August 1996 + + + number, even across power cycles. The internal structure of the port + number is opaque to the GSMP protocol. However, by looking up the + product identity in a database, network management tools may discover + the partitioning of the port number and the physical meaning of the + sub-fields. + + Each switch port also maintains a port session number assigned by the + switch. A connection management message or a port management message + with an incorrect port session number must be rejected. This allows + the controller to detect a link failure and to keep state + synchronized. The port session number of a port remains unchanged + while the port is continuously in the available state and the link + status is continuously up. When a port returns to the available state + after it has been unavailable or in any of the loopback states, or + when the line status returns to the up state after it has been down + or in test, or after a power cycle, its port session number will have + changed. Port session numbers should be assigned using some form of + random number. + + GSMP also contains an adjacency protocol. The adjacency protocol is + used to synchronize state across the link, to discover the identity + of the entity at the other end of a link, and to detect when it + changes. + + +2. GSMP Packet Format + + GSMP packets are variable length and are encapsulated directly in an + AAL-5 CPCS-PDU [I.363] with an LLC/SNAP header as illustrated: + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | LLC (0xAA-AA-03) | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + | SNAP (0x00-00-00-88-0C) | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + ~ GSMP Message ~ + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Pad (0 - 47 octets) | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + AAL-5 CPCS-PDU Trailer (8 octets) + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + + + +Newman, et. al. Informational [Page 4] + +RFC 1987 GSMP Protocol Specification August 1996 + + + (The convention in the documentation of Internet Protocols [rfc1700] + is to express numbers in decimal and to picture data in "big-endian" + order. That is, fields are described left to right, with the most + significant octet on the left and the least significant octet on the + right. Whenever a diagram shows a group of octets, the order of + transmission of those octets is the normal order in which they are + read in English. Whenever an octet represents a numeric quantity the + left most bit in the diagram is the high order or most significant + bit. That is, the bit labeled 0 is the most significant bit. + Similarly, whenever a multi-octet field represents a numeric quantity + the left most bit of the whole field is the most significant bit. + When a multi-octet quantity is transmitted, the most significant + octet is transmitted first. This is the same coding convention as is + used in the ATM layer [I.361] and AAL-5 [I.363].) + + The LLC/SNAP header contains the octets: 0xAA 0xAA 0x03 0x00 0x00 + 0x00 0x88 0x0C. + + The maximum transmission unit (MTU) of the GSMP message is 1500 + octets. + + The default virtual channel for LLC/SNAP encapsulated messages is: + + VPI = 0 + VCI = 15. + + GSMP is a master-slave protocol. The controller issues request + messages to the switch. Each request message indicates whether a + response is required from the switch and contains a transaction + identifier to enable the response to be associated with the request. + The switch replies with a response message indicating either a + successful result or a failure. There are four classes of GSMP + request-response message: Connection Management, Port Management, + Statistics, and Configuration. The switch may also generate + asynchronous Event messages to inform the controller of asynchronous + events. Event messages are not acknowledged by the controller. There + is also an adjacency protocol message used to establish + synchronization across the link and maintain a handshake. + + For the request-response messages each message type has a format for + the request message and a format for the success response. Unless + otherwise specified a failure response message is identical to the + request message that caused the failure, with the Code field + indicating the nature of the failure. Event messages have only a + single format defined as they are not acknowledged by the controller. + + Except for the adjacency protocol message, no GSMP messages may be + sent across the link until the adjacency protocol has achieved + + + +Newman, et. al. Informational [Page 5] + +RFC 1987 GSMP Protocol Specification August 1996 + + + synchronization, and all GSMP messages received on a link that does + not currently have state synchronization must be discarded. + + All GSMP messages, except the adjacency protocol message, have the + following format: + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + ~ Message Body ~ + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Version + The GSMP protocol version number, currently Version = 1. It + should be set by the sender of the message to the GSMP + protocol version that the sender is currently running. + + Message Type + The GSMP message type. GSMP messages fall into five + classes: Connection Management, Port Management, + Statistics, Configuration, and Events. Each class, except + for port management, has a number of different message + types. In addition, one Message Type is allocated to the + adjacency protocol. + + Result + Field in a connection management request message or a port + management request message, is used to indicate whether a + response is required to the request message if the outcome + is successful. A value of "NoSuccessAck" indicates that the + request message does not expect a response if the outcome + is successful, and a value of "AckAll" indicates that a + response is expected if the outcome is successful. In both + cases a failure response will be generated if the request + fails. This facility reduces the traffic in the case where + the controller is simply checking that the state in the + switch is correct. For all other request messages a value + of "NoSuccessAck" in the request message is ignored and the + request message is handled as if the field were set to + "AckAll". In a response message the result field can have + two values: "Success" and "Failure". + + + + +Newman, et. al. Informational [Page 6] + +RFC 1987 GSMP Protocol Specification August 1996 + + + The encoding of the result field is: + + NoSuccessAck: Result = 1 + AckAll: Result = 2 + Success: Result = 3 + Failure: Result = 4. + + + The Result field is not used in an adjacency protocol + message and should be set to zero by the sender and ignored + by the receiver. + + Code + Field gives further information concerning the result in a + response message. It is mostly used to pass an error code + in a failure response but can also be used to give further + information in a success response message or an event + message. In a request message the code field is not used + and is set to zero. In an adjacency protocol message the + Code field is used to determine the function of the + message. + + Transaction Identifier + Used to associate a request message with its response + message. For request messages the controller may select any + transaction identifier. For response messages the + transaction identifier is set to the value of the + transaction identifier from the message to which it is a + response. For event messages the transaction identifier + should be set to zero. In the adjacency protocol the + Transaction Identifier is not used. This field is not + present in the adjacency protocol message. + + +3. Connection Management Messages + + Connection management messages are used by the controller to + establish, delete, modify and verify connections across the switch. + The Add Branch, Delete Branch, Delete Tree, Verify Tree, and Delete + All connection management messages have the following format for both + request and response messages: + + + + + + + + + + +Newman, et. al. Informational [Page 7] + +RFC 1987 GSMP Protocol Specification August 1996 + + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port Session Number | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Input Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | Input VPI | Input VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Output Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | Output VPI | Output VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Number of Branches | Reserved | Priority | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Port Session Number + Field gives the session number of the input port. Each + switch port maintains a Port Session Number assigned by the + switch. The port session number of a port remains unchanged + while the port is continuously in the Available state and + the link status is continuously Up. When a port returns to + the Available state after it has been Unavailable or in any + of the Loopback states, or when the line status returns to + the Up state after it has been Down or in Test, or after a + power cycle, a new Port Session Number must be generated. + Port session numbers should be assigned using some form of + random number. The switch must reject any connection + management request message that has an invalid Port Session + Number for the port specified in the Input Port field by + returning a failure response message with the Code field + indicating, "Invalid port session number." The current port + session number may be obtained using a configuration + message. + + Input Port + Indicates a switch input port. Switch ports are referenced + by a 32 bit value assigned by the switch. + + Input VPI + Identifies an ATM virtual path arriving at the switch input + port indicated by the Input Port field. + + + + + +Newman, et. al. Informational [Page 8] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Input VCI + Identifies an ATM virtual channel arriving on the virtual + path indicated by the Input VPI field at the switch input + port indicated by the Input Port field. + + Output Port + Indicates a switch output port. Switch ports are + referenced by a 32 bit value assigned by the switch. + + Output VPI + Identifies an outgoing virtual path departing from the + switch output port indicated in the Output Port field. + + Output VCI + Identifies an outgoing virtual channel departing on the + virtual path indicated by the Output VPI field from the + switch output port indicated in the Output Port field. + + Number of Branches + Gives the number of output branches on a virtual channel + connection. (A unicast connection will have one branch, a + multicast connection will have two or more branches.) This + field is only used in the Verify Tree message. In all + other connection management messages this field should be + set to zero by the sender and ignored by the receiver. + + Reserved + This field is not used. It is set to zero by the sender and + ignored by the receiver. + + Priority + Gives the priority of the connection. The highest priority + is numbered zero and the lowest priority is numbered "Q-1" + where "Q" is the number of priorities that the output port + can support. The ability to offer different qualities of + service to different connections based upon their priority + is assumed to be a property of the output port of the + switch. It is assumed that for virtual channel connections + that share the same output port, an ATM cell on a + connection with a higher priority is much more likely to + exit the switch before an ATM cell on a connection with a + lower priority if they are both in the switch at the same + time. The number of priorities that each output port can + support is given in the Port Configuration message. If a + connection request is received with a value in the priority + field that the switch cannot support, the switch will + assign the closest priority that it is capable of + supporting. This field is only used in the Add Branch and + + + +Newman, et. al. Informational [Page 9] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Move Branch messages. In all other connection management + messages this field should be set to zero by the sender and + ignored by the receiver. + + If the result field of the request message is "AckAll" the switch + must reply to all connection management request messages with a + success response message or a failure response message. If the + result field of the request message is "NoSuccessAck" the switch must + only reply in the case of a failure. + + A success response message must not be sent until the operation has + been successfully completed. For connection management messages the + success response message is a copy of the request message returned + with a Result field indicating success. The Code field is not used in + a connection management success response message and should be set to + zero. The failure response message is a copy of the request message + returned with a Result field indicating failure. The Code field is + used to pass the Failure Code in a connection management failure + response message. If the switch issues a failure response the + connection state within the switch must not be modified by the + request message that resulted in the failure. + + No distinction is made between unicast connections and multicast + connections. The first Add Branch message for a particular Input + Port, Input VPI, and Input VCI will establish a unicast connection. + The second Add Branch message with the same Input Port, Input VPI, + and Input VCI fields will convert the connection to a multicast + connection with two branches. Subsequent Add Branch messages with the + same Input Port, Input VPI, and Input VCI fields will add further + branches to the multicast connection. Use of the Delete Branch + message on a multicast connection with two branches will result in a + unicast connection. Use of the Delete Branch message on a unicast + connection will delete the unicast connection. There is no concept of + a connection with zero output branches. All connections are + unidirectional, one input virtual channel to one or more output + virtual channels. + + The connection management messages may be issued regardless of the + Port Status of the switch port. Connections may be established or + deleted when a switch port is in the Available, Unavailable, or any + of the Loopback states. However, all connection state on an input + port will be deleted when the port returns to the Available state + from any other state, i.e. when a Port Management message is received + for that port with the Function field indicating either Bring Up, or + Reset Input Port. + + + + + + +Newman, et. al. Informational [Page 10] + +RFC 1987 GSMP Protocol Specification August 1996 + + +3.1 Add Branch Message + + The Add Branch message is a connection management message used to + establish a virtual channel connection or to add an additional branch + to an existing virtual channel connection. It may also be used to + check the connection state stored in the switch. The connection is + specified by the Input Port, Input VPI, and Input VCI fields. The + output branch is specified by the Output Port, Output VPI, and Output + VCI fields. The priority of the connection is specified by the + Priority field. The Add Branch message is: + + Message Type = 16 + + If the virtual channel connection specified by the Input Port, Input + VPI, and Input VCI fields does not already exist, it must be + established with the single output branch specified in the request + message. The output branch should have the priority specified by the + Priority field. If the Result field of the request message is + "AckAll" a success response message must be sent upon successful + establishment of the specified branch. The success response message + must not be sent until the Add Branch operation has been completed. + + If the virtual channel connection specified by the Input Port, Input + VPI, and Input VCI fields already exists, but the specified output + branch does not, the new output branch must be added. The new output + branch should have the priority specified by the Priority field. If + the Result field of the request message is "AckAll" a success + response message must be sent upon successful establishment of the + specified branch. The success response message must not be sent until + the Add Branch operation has been completed. + + If the virtual channel connection specified by the Input Port, Input + VPI, and Input VCI fields already exists and the specified output + branch also already exists, the priority of the connection, if + different from the request message, should be changed to that in the + request message. A success response message must be sent if the + Result field of the request message is "AckAll". This allows the + controller to periodically reassert the state of a connection or to + change its priority. If the result field of the request message is + "NoSuccessAck" a success response message should not be returned. + This may be used to reduce the traffic on the control link for + messages that are reasserting previously established state. For + messages that are reasserting previously established state, the + switch must always check that this state is correctly established in + the switch hardware (i.e. the actual connection tables used to + forward cells). + + + + + +Newman, et. al. Informational [Page 11] + +RFC 1987 GSMP Protocol Specification August 1996 + + + The behavior is undefined if the output virtual channel specified by + the Output Port, Output VPI, and Output VCI fields is already in use + by any connection other than that specified by the Input Port, Input + VPI, and Input VCI fields. + + A failure response must be returned if the switch is unable to + establish the specified branch or if there is an error in any of the + fields of the request message. If a failure message is returned the + state of the switch must not have been modified by the request + message. + + It should be noted that different switches support multicast in + different ways. There will be a limit to the total number of + multicast connections any switch can support, and possibly a limit on + the maximum number of branches that a multicast connection may + specify. Some switches also impose a limit on the number of + different VPI/VCI values that may be assigned to the output branches + of a multicast connection. Many switches are incapable of supporting + more than a single branch of any particular multicast connection on + the same output port. Specific failure codes are defined for some of + these conditions. If a switch sends a failure response to an Add + Branch message it must choose the most specific failure code. + +3.2 Delete Branch Message + + The Delete Branch message is a connection management message used to + delete a single branch of a virtual channel connection, or in the + case of the last branch, to delete the connection. The virtual + channel connection is specified by the Input Port, Input VPI, and + Input VCI fields. The specific branch is indicated by the Output + Port, Output VPI, and Output VCI fields. The Delete Branch message + is: + + Message Type = 17 + + If the Result field of the request message is "AckAll" a success + response message must be sent upon successful deletion of the + specified branch. The success response message must not be sent until + the delete branch operation has been completed and if possible, not + until all data on that branch, queued for transmission, has been + transmitted. A failure message indicating, "The specified connection + does not exist," must be sent if the connection specified by the + Input Port, Input VPI, and Input VCI fields does not exist. A failure + message indicating, "The specified branch does not exist," must be + sent if the connection specified by the Input Port, Input VPI, and + Input VCI fields exists but the branch specified by the Output Port, + Output VPI, and Output VCI fields does not exist. + + + + +Newman, et. al. Informational [Page 12] + +RFC 1987 GSMP Protocol Specification August 1996 + + +3.3 Delete Tree Message + + The Delete Tree message is a connection management message used to + delete an entire virtual channel connection. All remaining branches + of the connection are deleted. The virtual channel connection is + specified by the Input Port, Input VPI, and Input VCI fields. The + Output Port, Output VPI, and Output VCI fields are not used in this + message and their contents should be set to zero by the sender and + ignored by the receiver. The Delete Tree message is: + + Message Type = 18 + + If the Result field of the request message is "AckAll" a success + response message must be sent upon successful deletion of the + specified connection. The success message must not be sent until the + delete operation has been completed and if possible, not until all + data on the connection, queued for transmission, has been + transmitted. A failure message indicating, "The specified connection + does not exist," must be sent if the connection specified by the + Input Port, Input VPI, and Input VCI fields does not exist. + +3.4 Verify Tree Message + + The Verify Tree message is a connection management message used to + verify the number of branches on a virtual channel connection. The + virtual channel connection is specified by the Input Port, Input VPI, + and Input VCI fields. The Output Port, Output VPI, and Output VCI + fields are not used in this message and their contents should be set + to zero by the sender and ignored by the receiver. The number of + branches that the sender believes that this virtual channel + connection should contain is given by the Number of Branches field. + The Verify Tree message is: + + Message Type = 19 + + If the Result field of the request message is "AckAll" a success + response message must be sent if the receiver agrees that the actual + number of branches of the specified virtual channel connection + matches the number contained in the Number of Branches field of the + request message. The failure response message, with the code field + set to "Failure specific to the particular message type," must be + sent if the actual number of branches of the specified virtual + channel connection does not match the number contained in the Number + of Branches field of the request message. In this failure response + message the Number of Branches field must be changed to contain the + actual number of branches of the specified virtual channel + connection. A failure response message with the code field set to a + different value must be used to indicate some other failure such as, + + + +Newman, et. al. Informational [Page 13] + +RFC 1987 GSMP Protocol Specification August 1996 + + + "The specified connection does not exist." In this case the Number of + Branches field will be the same as that of the request message. + + The Verify Tree message can only be guaranteed to yield a correct + response when there are no other connection request messages or their + response messages pending for the specified connection. If this is + not the case the result of the Verify Tree message is undefined. + +3.5 Delete All Message + + The Delete All message is a connection management message used to + delete all connections on a switch input port. All connections that + arrive at the specified input port must be deleted. On completion of + the operation all dynamically assigned VPI/VCI values for the + specified port must be unassigned, i.e. there must be no virtual + connections established in the VPI/VCI space that GSMP controls on + this port. The Input VPI, Input VCI, Output Port, Output VPI, and + Output VCI fields are not used in this message and their contents are + ignored and unspecified. The Delete All message is" + + Message Type = 20 + + If the Result field of the request message is "AckAll" a success + response message must be sent upon completion of the operation. The + success response message must not be sent until the operation has + been completed. + + +3.6 Move Branch Message + + The Move Branch connection management message has the following + format for both request and response messages: + + + + + + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 14] + +RFC 1987 GSMP Protocol Specification August 1996 + + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port Session Number | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Input Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | Input VPI | Input VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Old Output Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | Old Output VPI | Old Output VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | New Output Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | New Output VPI | New Output VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Reserved | Priority | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + The Move Branch message is a connection management message used to + move a single output branch of a virtual channel connection from its + current output port, output VPI, and output VCI, to a new output + port, output VPI, and output VCI on the same virtual channel + connection. None of the other output branches are modified. When the + operation is complete the original output VPI/VCI on the original + output port will be deleted from the connection. The Move Branch + message is: + + Message Type = 22 + + If the virtual channel connection specified by the Input Port, Input + VPI, and Input VCI fields already exists, and the output branch + specified by the Old Output Port, Old Output VPI, and Old Output VCI + fields exists as a branch on that connection, the output branch + specified by the New Output Port, New Output VPI, and New Output VCI + fields is added to the connection and the branch specified by the Old + Output Port, Old Output VPI, and Old Output VCI fields is deleted. If + the Result field of the request message is "AckAll" a success + response message must be sent upon successful completion of the + operation. The success response message must not be sent until the + Move Branch operation has been completed. + + + + + +Newman, et. al. Informational [Page 15] + +RFC 1987 GSMP Protocol Specification August 1996 + + + If the virtual channel connection specified by the Input Port, Input + VPI, and Input VCI fields already exists, but the output branch + specified by the Old Output Port, Old Output VPI, and Old Output VCI + fields does not exist as a branch on that connection, a failure + response must be returned with the Code field indicating, "The + specified branch does not exist." The connection state of the switch + must not be modified in this case. + + If the virtual channel connection specified by the Input Port, Input + VPI, and Input VCI fields does not exist, a failure response must be + returned with the Code field indicating, "The specified connection + does not exist." The connection state of the switch must not be + modified in this case. + + The behavior is undefined if the output virtual channel specified by + the New Output Port, New Output VPI, and New Output VCI fields is + already in use by any connection. + + A failure response will be returned if the switch is unable to + establish the specified branch or if there is an error in any of the + fields of the request message. If a failure message is returned the + state of the switch must not have been modified by the request + message. + +4. Port Management Message + + The Port Management message allows a port to be brought into service, + taken out of service, looped back, or reset. Only the Bring Up and + the Reset Input Port functions change the connection state + (established connections) on the input port. Only the Bring Up + function changes the value of the Port Session Number. If the Result + field of the request message is "AckAll" a success response message + must be sent upon successful completion of the operation. The success + response message must not be sent until the operation has been + completed. The Port Management Message is: + + Message Type = 32 + + The Port Management message has the following format for the request + and success response messages: + + + + + + + + + + + +Newman, et. al. Informational [Page 16] + +RFC 1987 GSMP Protocol Specification August 1996 + + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port Session Number | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Event Sequence Number | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Event Flags | Duration | Function | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Port + Gives the port number of the port to which the message + applies. + + Port Session Number + Gives the current port session number for the port. If the + Port Session Number in the request message does not match + the current port session number of the port indicated by + the Port field of the request message, a failure response + must be returned with, "Invalid port session number," + indicated in the Code field. If the specified function + requires a new Port Session Number to be generated the new + Port Session Number must be given in the success response + message. The Port Session Number must be generated using + some form of random number. + + Event Sequence Number + In the success response message gives the current value of + the Event Sequence Number of the switch port indicated by + the Port field. The Event Sequence Number is set to zero + when the port is initialized and is incremented by one each + time an asynchronous event is detected on that port that + the switch would normally report via an Event message. If + the Event Sequence Number in the success response differs + from the Event Sequence Number of the most recent Event + message received for that port, events have occurred that + were not reported via an Event message. This is most likely + to be due to the flow control that restricts the rate at + which a switch can send Event messages for each port. In + the request message this field is not used and should be + set to zero by the sender and ignored by the receiver. + + + + +Newman, et. al. Informational [Page 17] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Event Flags + Field in the request message is used to reset the Event + Flags in the switch port indicated by the Port field. Each + Event Flag in a switch port corresponds to a type of Event + message. When a switch port sends an Event message it sets + the corresponding Event Flag on that port. The port is not + permitted to send another Event message of the same type + until the Event Flag has been reset. If the Function field + in the request message is set to "Reset Event Flags," for + each bit that is set in the Event Flags field, the + corresponding Event Flag in the switch port is reset. + + The Event Flags field is only used in a request message + with the Function field set to "Reset Event Flags." For all + other values of the Function field, the Event Flags field + should be set to zero in the request message and must be + ignored by the receiver. In the success response message + the Event Flags field must be set to the current value of + the Event Flags for the port, after the completion of the + operation specified by the request message, for all values + of the Function field. Setting the Event Flags field to all + zeros in a "Reset Event Flags" request message allows the + controller to obtain the current state of the Event Flags + and the current Event Sequence Number of the port without + changing the state of the Event Flags. + + The correspondence between the types of Event message and + the bits of the Event Flags field is as follows: + + Port Up: Bit 0, (most significant bit) + Port Down: Bit 1, + Invalid VPI/VCI: Bit 2, + New Port: Bit 3, + Dead Port: Bit 4. + + Duration + Is the length of time, in seconds, that any of the loopback + states remain in operation. When the duration has expired + the port will automatically be returned to service. If + another Port Management message is received for the same + port before the duration has expired, the loopback will + continue to remain in operation for the length of time + specified by the Duration field in the new message. The + Duration field is only used in request messages with the + Function field set to Internal Loopback, External Loopback, + or Bothway Loopback. In all other request messages it + should be set to zero by the sender and ignored by the + receiver. + + + +Newman, et. al. Informational [Page 18] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Function + Specifies the action to be taken. The specified action will + be taken regardless of the current status of the port + (Available, Unavailable, or any Loopback state). The + defined values of the Function field are: + + Bring Up: + Function = 1. Bring the port into service. All + connections that arrive at the specified input port + must be deleted and a new Port Session Number must be + selected using some form of random number. On + completion of the operation all dynamically assigned + VPI/VCI values for the specified input port must be + unassigned, i.e. no virtual connections will be + established in the VPI/VCI space that GSMP controls on + this input port. The Port Status of the port + afterwards will be Available. + + Take Down: + Function = 2. Take the port out of service. Any cells + received at this port will be discarded. No cells will + be transmitted from this port. The Port Status of the + port afterwards will be Unavailable. The behavior is + undefined if the port over which the GSMP protocol is + running is taken down. + + Internal Loopback: + Function = 3. Cells arriving at the output port from + the switch fabric are looped through to the input port + to return to the switch fabric. All of the ATM + functions of the input port above the PHY layer, e.g. + header translation, are performed upon the looped back + cells. The Port Status of the port afterwards will be + Internal Loopback. + + External Loopback: + Function = 4. Cells arriving at the input port from + the external communications link are immediately + looped back to the communications link at the physical + layer without entering the input port. None of the ATM + functions of the input port above the PHY layer are + performed upon the looped back cells. The Port Status + of the port afterwards will be External Loopback. + + Bothway Loopback: + Function = 5. Both internal and external loopback are + performed. The Port Status of the port afterwards will + be Bothway Loopback. + + + +Newman, et. al. Informational [Page 19] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Reset Input Port: + Function = 6. All connections that arrive at the + specified input port must be deleted and the input and + output port hardware re-initialized. On completion of + the operation all dynamically assigned VPI/VCI values + for the specified input port must be unassigned, i.e. + no virtual connections will be established in the + VPI/VCI space that GSMP controls on this input port. + The Port Session Number is not changed by the Reset + Input Port function. The Port Status of the port + afterwards will be Unavailable. + + Reset Event Flags: + Function = 7. For each bit that is set in the Event + Flags field, the corresponding Event Flag in the + switch port must be reset. The Port Status of the port + is not changed by this function. + + +5. Statistics Messages + + The statistics messages permit the controller to request the values + of various hardware counters associated with the switch input and + output ports, and virtual channels. Two classes of statistics message + are defined: the VC Activity Message, and the Port and VC Statistics + Messages. The VC Activity message is used to determine whether one or + more specific VCs have recently been carrying traffic. The Port and + VC Statistics message is used to query the various port and VC + specific traffic and error counters. + +5.1 VC Activity Message + + The VC Activity message is used to determine whether one or more + specific VCs have recently been carrying traffic. The VC Activity + message contains one or more VC Activity records. Each VC Activity + record is used to request and return activity information concerning + a single virtual connection. Each VC is specified by its input port, + input VPI, and input VCI. These are specified in the Input Port, + Input VPI, and Input VCI fields of each VC Activity record. Two + forms of activity detection are supported. If the switch supports per + VC traffic accounting the current value of the traffic counter for + each specified VC must be returned. The units of traffic counted are + not specified but will typically be either cells or frames. The + controller must compare the traffic counts returned in the message + with previous values for each of the specified VCs to determine + whether each VC has been active in the intervening period. If the + switch does not support per VC traffic accounting, but is capable of + detecting per-VC activity by some other unspecified means, the result + + + +Newman, et. al. Informational [Page 20] + +RFC 1987 GSMP Protocol Specification August 1996 + + + may be indicated for each VC using the Flags field. The VC Activity + message is: + + Message Type = 48 + + The VC Activity request and success response messages have the + following format: + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Number of Records | Reserved | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + ~ VC Activity Records ~ + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Number of Records + Field specifies the number of VC Activity records to + follow. The maximum number of VC Activity records permitted + in a single VC Activity message is 120. + + Reserved + Field is not used. It is set to zero by the sender and + ignored by the receiver. + + Each VC Activity Record has the following format: + + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Input Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Flags | Input VPI | Input VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + VC Traffic Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Input Port + Identifies the port number of the input port on which the + VC of interest arrives in order to identify the VC + (regardless of whether the traffic count for the VC is + maintained on the input port or the output port). + + + +Newman, et. al. Informational [Page 21] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Input VPI + Input VCI + Fields identify the specific virtual channel for which + statistics are being requested. + + Flags + In the request message this field is unused, it should be + set to zero by the sender and ignored by the receiver. In + the success response message bit 0 (msb) of the Flags field + is used to indicate an invalid VC Activity record. This bit + must be zero if any of the fields in this VC Activity + record are invalid, if the input port specified by the + Input Port field does not exist, or if the specified + connection does not exist. If this bit is zero in a success + response message bits 1 and 2 of the Flags field and the VC + Traffic Count field are undefined. If bit 0 of the flags + field is set, the VC Activity record is valid, and bits 1 + and 2 of the Flags field in the VC Activity record are used + as follows: + + Bit 1 of the Flags field: if set, indicates that the + value in bit 2 of the Flags field is valid; if zero, + indicates that the value in the VC Traffic Count field + is valid. + + If bit 1 of the Flags field is set, bit 2 of the Flags + field, if set, indicates that there has been some + activity on this virtual channel since the last VC + Activity message for this virtual channel. + + If bit 1 of the Flags field is set, bit 2 of the Flags + field, if zero, indicates that there has been no + activity on this virtual channel since the last VC + Activity message for this virtual channel. + + Bit 3 of the Flags field is not used, it should be set + to zero by the sender and ignored by the receiver. + + VC Traffic Count + Field is unused in the request message, it should be set to + zero by the sender and ignored by the receiver. In the + success response message, if the switch supports per-VC + traffic counting, the VC Traffic Count field must be set to + the value of a free running, VC specific, 64 bit traffic + counter counting traffic flowing across the specified + virtual channel. The value of the traffic counter is not + modified by reading it. If per-VC traffic counting is + supported, the switch must report the VC Activity result + + + +Newman, et. al. Informational [Page 22] + +RFC 1987 GSMP Protocol Specification August 1996 + + + using the traffic count rather than using bit 2 of the + Flags field. + + The format of the failure response is the same as the request message + with the Number of Records field set to zero and no VC Activity + records returned in the message. If the switch is incapable of + detecting per-VC activity, a failure response must be returned + indicating, "The specified request is not implemented on this + switch." + +5.2 Port and VC Statistics Messages + + The Port and VC Statistics messages are used to query the various + port and VC specific traffic and error counters. + + The Port and VC Statistics request messages have the following + format: + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | VPI | VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Port + Identifies the port number of the port for which statistics + are being requested. + + VPI + VCI + Fields identify the specific virtual channel for which + statistics are being requested. For requests that do not + require a virtual channel to be specified these fields + should be set to zero in the request and ignored by the + receiver. + + The success response messages for the port and VC statistics group + have the following format: + + + + + + + +Newman, et. al. Informational [Page 23] + +RFC 1987 GSMP Protocol Specification August 1996 + + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | VPI | VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Input Cell Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Input Frame Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Input Cell Discard Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Input Frame Discard Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Input HEC Error Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Input Invalid VPI/VCI Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Output Cell Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Output Frame Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + Output Cell Discard Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + + + +Newman, et. al. Informational [Page 24] + +RFC 1987 GSMP Protocol Specification August 1996 + + + + Output Frame Discard Count + + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Port + VPI/VCI + Fields are the same as those of the request message. + + Input Cell Count + Output Cell Count + Each gives the value of a free running 64 bit counter + counting cells arriving at the input or departing from the + output respectively. In response to a Port Statistics + message the count will be on a per port basis and in + response to a VC Statistics message the count will be on a + per VC basis. + + Input Frame Count + Output Frame Count + Each gives the value of a free running 64 bit counter + counting frames (packets) arriving at the input or + departing from the output respectively. In response to a + Port Statistics message the count will be on a per port + basis and in response to a VC Statistics message the count + will be on a per VC basis. + + Input Cell Discard Count + Output Cell Discard Count + Each gives the value of a free running 64 bit counter + counting cells discarded due to queue overflow on an input + port or on an output port respectively. In response to a + Port Statistics message the count will be on a per port + basis and in response to a VC Statistics message the count + will be on a per VC basis. + + Input Frame Discard Count + Output Frame Discard Count + Each gives the value of a free running 64 bit counter + counting frames discarded due to queue overflow on an input + port or on an output port respectively. In response to a + Port Statistics message the count will be on a per port + basis and in response to a VC Statistics message the count + will be on a per VC basis. + + HEC Error Count + Gives the value of a free running 64 bit counter counting + cells discarded due to header checksum errors on arrival at + an input port. + + + +Newman, et. al. Informational [Page 25] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Invalid VPI/VCI Count + Gives the value of a free running 64 bit counter counting + cells discarded because their VPI/VCI is invalid on arrival + at an input port. An incoming VPI/VCI is invalid if no + connection is currently established having that value of + VPI/VCI. + +5.2.1 Port Statistics Message + + The Port Statistics message requests the statistics for the switch + port specified in the Port field. The contents of the VPI/VCI field + in the Port Statistics request message are ignored. All of the count + fields in the success response message refer to per-port counts + regardless of the virtual channels to which the cells belong. Any of + the count fields in the success response message not supported by the + port will be set to zero. The Port Statistics message is: + + Message Type = 49 + +5.2.2 VC Statistics Message + + The VC Statistics message requests the statistics for the virtual + channel specified in the VPI/VCI field that arrives on the switch + input port specified in the Port field. All of the count fields in + the success response message refer only to the specified virtual + channel. The HEC Error Count and Invalid VPI/VCI Count fields are not + VC specific and are set to zero. Any of the other count fields not + supported on a per virtual channel basis will be set to zero in the + success response message. The VC Statistics message is: + + Message Type = 50 + +6. Configuration + + The configuration messages permit the controller to discover the + capabilities of the switch. Three configuration request messages have + been defined: Switch, Port, and All Ports. + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 26] + +RFC 1987 GSMP Protocol Specification August 1996 + + + All configuration request messages have the following format: + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Port + Identifies the port number for which configuration + information is being requested. If the Port field is not + required by the message it is set to zero by the sender and + ignored by the receiver. + +6.1 Switch Configuration Message + + The Switch Configuration message requests the global (non port- + specific) configuration for the switch. The Switch Configuration + message is: + + Message Type = 64 + + The Port field is not used in the request message and is set to zero. + + The Switch Configuration success response message has the following + format: + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Firmware Version Number | Reserved | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Switch Type | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + | Switch Name | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Firmware Version Number + The version number of the switch control firmware + installed. + + + +Newman, et. al. Informational [Page 27] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Reserved + Field is not used. It is set to zero by the sender and + ignored by the receiver. + + Switch Type + A 16 bit field allocated by the manufacturer of the switch. + (For these purposes the manufacturer of the switch is + assumed to be the organization identified by the OUI in the + Switch Name field.) The Switch Type identifies the product. + When the Switch Type is combined with the OUI from the + Switch Name the product is uniquely identified. Network + Management may use this identification to obtain product + related information from a database. + + Switch Name + A 48 bit quantity that is unique within the operational + context of the device. A 48 bit IEEE 802 MAC address, if + available, may be used as the Switch Name. The most + significant 24 bits of the Switch Name must be an + Organizationally Unique Identifier (OUI) that identifies + the manufacturer of the switch. + +6.2 Port Configuration Message + + The Port Configuration message requests the switch for the + configuration information of a single switch port. The Port field in + the request message specifies the port for which the configuration is + requested. The Port Configuration message is: + + Message Type = 65. + + The Port Configuration success response message has the following + format: + + + + + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 28] + +RFC 1987 GSMP Protocol Specification August 1996 + + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port Session Number | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | Min VPI | zero | Max VPI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Min VCI | Max VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Cell Rate | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port Status | Port Type | Line Status | Priorities | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Port + The switch port to which the configuration information + refers. Configuration information relating to both the + input and the output sides of the switch port is given. + Port numbers are 32 bits wide and allocated by the switch. + The switch may choose to structure the 32 bits into sub + fields that have meaning to the physical structure of the + switch hardware (e.g. shelf, slot, interface). + + Port Session Number + The current Port Session Number for the specified port. + Each switch port maintains a Port Session Number assigned + by the switch. The Port Session Number of a port remains + unchanged while the port is continuously in the Available + state. When a port returns to the Available state after it + has been Unavailable, or after a power cycle, its Port + Session Number must be changed, preferably using some form + of random number. + + Min VPI + The minimum value of dynamically assigned incoming VPI that + the connection table on the input port can support and may + be controlled by GSMP. + + Max VPI + The maximum value of dynamically assigned incoming VPI that + the connection table on the input port can support and may + be controlled by GSMP. It is assumed that the input port + + + +Newman, et. al. Informational [Page 29] + +RFC 1987 GSMP Protocol Specification August 1996 + + + can handle all values of VPI within the range Min VPI to + Max VPI inclusive and that GSMP may control all values + within this range. If the switch does not support virtual + paths it is acceptable for both Min VPI and Max VPI to + specify the same value, most likely zero. + + Min VCI + The minimum value of dynamically assigned incoming VCI that + the connection table on the input port can support and may + be controlled by GSMP. + + Max VCI + The maximum value of dynamically assigned incoming VCI that + the connection table on the input port can support and may + be controlled by GSMP. It is assumed that the input port + can handle all values of VCI within the range Min VCI to + Max VCI inclusive for each of the virtual paths in the + range Min VPI to Max VPI inclusive and that GSMP may + control all values within this range. + + Cell Rate + A measure of the bandwidth of the port. It is the rate of + cells arriving at or departing from the port in cells/s. It + is assumed that both input port and output port have the + same cell rate. + + Port Status + Gives the administrative state of the port. The defined + values of the Port Status field are: + + Available: + Port Status = 1. The port is available to both send + and receive cells. When a port changes to the + Available state from any other administrative state, + all dynamically assigned virtual connections must be + cleared and a new Port Session Number must be + generated. + + Unavailable: + Port Status = 2. The port has intentionally been taken + out of service. No cells will be transmitted from this + port. No cells will be received by this port. + + Internal Loopback: + Port Status = 3. The port has intentionally been taken + out of service and is in internal loopback: cells + arriving at the output port from the switch fabric are + looped through to the input port to return to the + + + +Newman, et. al. Informational [Page 30] + +RFC 1987 GSMP Protocol Specification August 1996 + + + switch fabric. All of the ATM functions of the input + port above the PHY layer, e.g. header translation, are + performed upon the looped back cells. + + External Loopback: + Port Status = 4. The port has intentionally been taken + out of service and is in external loopback: cells + arriving at the input port from the external + communications link are immediately looped back to the + communications link at the physical layer without + entering the input port. None of the ATM functions of + the input port above the PHY layer are performed upon + the looped back cells. + + Bothway Loopback: + Port Status = 5. The port has intentionally been taken + out of service and is in both internal and external + loopback. + + Port Type + The type of physical transmission interface for this port. + The values for this field are given by the IANAifTYPE + object from the MIB defined for the IANAifTYPE-MIB + specified in RFC 1573 [rfc1573]. Example values are: SONET + or SDH (39), DS-3 (30). + + Line Status + The status of the physical transmission medium connected to + the port. The defined values of the Line Status field are: + + Up: + Line Status = 1. The line is able to both send and + receive cells. When the Line Status changes to Up + from either the Down or Test states, a new Port + Session Number must be generated. + + Down: + Line Status = 2. The line is unable either to send or + receive cells or both. + + Test: + Line Status = 3. The port or line is in a test mode, + for example, power-on test. + + Priorities + The number of different priorities that this output port + can assign to virtual channel connections. Zero is invalid + in this field. If an output port is able to support "Q" + + + +Newman, et. al. Informational [Page 31] + +RFC 1987 GSMP Protocol Specification August 1996 + + + priorities, the highest priority is numbered zero and the + lowest priority is numbered "Q-1". The ability to offer + different qualities of service to different connections + based upon their priority is assumed to be a property of + the output port of the switch. It may be assumed that for + virtual channel connections that share the same output + port, an ATM cell on a connection with a higher priority is + much more likely to exit the switch before an ATM cell on a + connection with a lower priority if they are both in the + switch at the same time. + +6.3 All Ports Configuration Message + + The All Ports Configuration message requests the switch for the + configuration information of all of its ports. The All Ports + Configuration message is: + + Message Type = 66 + + The Port field is not used in the request message and is set to zero. + + The All Ports Configuration success response message has the + following format: + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Number of Records | Port Record Length | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | + ~ Port Records ~ + | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Number of Records + Field gives the number of Port Records to follow in the + message. The maximum number of port records allowed in a + single All Ports Configuration success response is 64. If a + switch has more than 64 ports it must send them in multiple + success response messages. + + Port Record Length + Field gives the length of each port record in bytes. This + is currently 24 but the Port Record Length field allows for + + + +Newman, et. al. Informational [Page 32] + +RFC 1987 GSMP Protocol Specification August 1996 + + + the future definition of further fields at the end of the + port record while preserving compatibility with earlier + versions of the protocol. + + Port Records follow in the remainder of the message. Each port record + has the following format: + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port Session Number | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | Min VPI | zero | Max VPI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Min VCI | Max VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Cell Rate | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port Status | Port Type | Line Status | Priorities | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + The definition of the fields in the port record is exactly the same + as that of the Port Configuration message. + +7. Event Messages + + Event messages allow the switch to inform the controller of certain + asynchronous events. Event messages are not acknowledged. The Result + field and the Code field in the message header are not used and + should be set to zero. Event messages are not sent during + initialization. Event messages have the following format: + + + + + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 33] + +RFC 1987 GSMP Protocol Specification August 1996 + + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Transaction Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Port Session Number | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Event Sequence Number | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | zero | VPI | VCI | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Port + Field gives the switch port to which the event message + refers. + + Port Session Number + The current Port Session Number for the specified port. + + Event Sequence Number + The current value of the Event Sequence Number for the + specified port. The Event Sequence Number is set to zero + when the port is initialized and is incremented by one each + time an asynchronous event is detected on that port that + the switch would normally report via an Event message. The + Event Sequence Number must be incremented each time an + event occurs even if the switch is prevented from sending + an Event message due to the action of the flow control. + + VPI/VCI + Field gives the VPI/VCI to which the event message refers. + If this field is not required by the event message it is + set to zero. + + Each switch port must maintain an Event Sequence Number and a set of + Event Flags, one Event Flag for each type of Event message. When a + switch port sends an Event message it must set the Event Flag on that + port corresponding to the type of the event. The port is not + permitted to send another Event message of the same type until the + Event Flag has been reset. Event Flags are reset by the "Reset Event + Flags" function of the Port Management message. This is a simple flow + control preventing the switch from flooding the controller with event + messages. The Event Sequence Number of the port must be incremented + every time an event is detected on that port even if the port is + + + +Newman, et. al. Informational [Page 34] + +RFC 1987 GSMP Protocol Specification August 1996 + + + prevented from reporting the event due to the action of the flow + control. This allows the controller to detect that it has not been + informed of some events that have occurred on the port due to the + action of the flow control. + +7.1 Port Up Message + + The Port Up message informs the controller that the Line Status of a + port has changed from either the Down or Test state to the Up state. + When the Line Status of a switch port changes to the Up state from + either the Down or Test state a new Port Session Number must be + generated, preferably using some form of random number. The new Port + Session Number is given in the Port Session Number field. The VPI/VCI + field is not used and is set to zero. The Port Up message is: + + Message Type = 80 + +7.2 Port Down Message + + The Port Down message informs the controller that the Line Status of + a port has changed from the Up state to the Down state. This message + will be sent to report link failure if the switch is capable of + detecting link failure. The port session number that was valid before + the port went down is reported in the Port Session Number field. The + VPI/VCI field is not used and is set to zero. The Port Down message + is: + + Message Type = 81 + +7.3 Invalid VPI/VCI Message + + The Invalid VPI/VCI message is sent to inform the controller that one + or more cells have arrived at an input port with a VPI/ VCI that is + currently not allocated to an assigned connection. The input port is + indicated in the Port field, and the VPI/VCI in the VPI/VCI field. + The Invalid VPI/VCI message is: + + Message Type = 82 + +7.4 New Port Message + + The New Port message informs the controller that a new port has been + added to the switch. The port number of the new port is given in the + Port field. A new Port Session Number must be assigned, preferably + using some form of random number. The new Port Session Number is + given in the Port Session Number field. The state of the new port is + undefined so the VPI/VCI field is not used and is set to zero. The + New Port message is: + + + +Newman, et. al. Informational [Page 35] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Message Type = 83 + +7.5 Dead Port Message + + The Dead Port message informs the controller that a port has been + removed from the switch. The port number of the port is given in the + Port field. The Port Session Number that was valid before the port + was removed is reported in the Port Session Number field. The + VPI/VCI fields are not used and are set to zero. The Dead Port + message is: + + Message Type = 84 + +8. Adjacency Protocol + + The adjacency protocol is used to synchronize state across the link, + to discover the identity of the entity at the other end of a link, + and to detect when it changes. No GSMP messages other than those of + the adjacency protocol may be sent across the link until the + adjacency protocol has achieved synchronization. + +8.1 Packet Format + + The adjacency protocol is: + + Message Type = 10 + + All GSMP messages belonging to the adjacency protocol have the + following structure: + + + + + + + + + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 36] + +RFC 1987 GSMP Protocol Specification August 1996 + + + 0 1 2 3 + 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Version | Message Type | Result | Code | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Sender Name | + + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | | | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + | Receiver Name | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Sender Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Receiver Port | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Sender Instance | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Receiver Instance | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Version + The GSMP protocol version number, currently Version = 1. It + should be set by the sender of the message to the GSMP + protocol version that the sender is currently running. + + Result + Field is not used in the adjacency protocol. It should be + set to zero by the sender and ignored by the receiver. + + Code + Field specifies the function of the message. Four Codes are + defined for the adjacency protocol: + + SYN: Code = 1 + SYNACK: Code = 2 + ACK: Code = 3 + RSTACK: Code = 4. + + Sender Name + For the SYN, SYNACK, and ACK messages, is the name of the + entity sending the message. The Sender Name is a 48 bit + quantity that is unique within the operational context of + the device. A 48 bit IEEE 802 MAC address, if available, + may be used for the Sender Name. For the RSTACK message, + the Sender Name field is set to the value of the Receiver + Name field from the incoming message that caused the RSTACK + message to be generated. + + + + +Newman, et. al. Informational [Page 37] + +RFC 1987 GSMP Protocol Specification August 1996 + + + Receiver Name + For the SYN, SYNACK, and ACK messages, is the name of the + entity that the sender of the message believes is at the + far end of the link. If the sender of the message does not + know the name of the entity at the far end of the link, + this field should be set to zero. For the RSTACK message, + the Receiver Name field is set to the value of the Sender + Name field from the incoming message that caused the RSTACK + message to be generated. + + Sender Port + For the SYN, SYNACK, and ACK messages, is the local port + number of the link across which the message is being sent. + Port numbers are locally assigned 32 bit values. For the + RSTACK message, the Sender Port field is set to the value + of the Receiver Port field from the incoming message that + caused the RSTACK message to be generated. + + Receiver Port + For the SYN, SYNACK, and ACK messages, is what the sender + believes is the local port number for the link, allocated + by the entity at the far end of the link. If the sender of + the message does not know the port number at the far end of + the link, this field should be set to zero. For the RSTACK + message, the Receiver Port field is set to the value of the + Sender Port field from the incoming message that caused the + RSTACK message to be generated. + + Sender Instance + For the SYN, SYNACK, and ACK messages, is the sender's + instance number for the link. It is used to detect when the + link comes back up after going down or when the identity of + the entity at the other end of the link changes. The + instance number is a 32 bit number that is guaranteed to be + unique within the recent past and to change when the link + or node comes back up after going down. Zero is not a valid + instance number. For the RSTACK message, the Sender + Instance field is set to the value of the Receiver Instance + field from the incoming message that caused the RSTACK + message to be generated. + + Receiver Instance + For the SYN, SYNACK, and ACK messages, is what the sender + believes is the current instance number for the link, + allocated by the entity at the far end of the link. If the + sender of the message does not know the current instance + number at the far end of the link, this field should be set + to zero. For the RSTACK message, the Receiver Instance + + + +Newman, et. al. Informational [Page 38] + +RFC 1987 GSMP Protocol Specification August 1996 + + + field is set to the value of the Sender Instance field from + the incoming message that caused the RSTACK message to be + generated. + +8.2 Procedure + + The adjacency protocol is described by the rules and state tables + given in this section. + + The rules and state tables use the following operations: + + o The "Update Peer Verifier" operation is defined as storing the + values of the Sender Instance, Sender Port, and Sender Name fields + from a SYN or SYNACK message received from the entity at the far + end of the link. + + o The procedure "Reset the link" is defined as: + + 1. Generate a new instance number for the link + 2. Delete the peer verifier (set to zero the values of Sender + Instance, Sender Port, and Sender Name previously stored by + the Update Peer Verifier operation) + 3. Send a SYN message + 4. Enter the SYNSENT state + + o The state tables use the following Boolean terms and operators: + + A The Sender Instance in the incoming message matches the + value stored from a previous message by the "Update Peer + Verifier" operation. + + B The Sender Instance, Sender Port, and Sender Name fields in + the incoming message match the values stored from a + previous message by the "Update Peer Verifier" operation. + + C The Receiver Instance, Receiver Port, and Receiver Name + fields in the incoming message match the values of the + Sender Instance, Sender Port, and Sender Name currently + sent in outgoing SYN, SYNACK, and ACK messages. + + "&&" Represents the logical AND operation + + "||" Represents the logical OR operation + + "!" Represents the logical negation (NOT) operation. + + + + + + +Newman, et. al. Informational [Page 39] + +RFC 1987 GSMP Protocol Specification August 1996 + + + o A timer is required for the periodic generation of SYN, SYNACK, + and ACK messages. The period of the timer is unspecified but a + value of one second is suggested. + + There are two independent events: the timer expires, and a packet + arrives. The processing rules for these events are: + + Timer Expires: Reset Timer + If state = SYNSENT Send SYN + If state = SYNRCVD Send SYNACK + If state = ESTAB Send ACK + + Packet Arrives: If incoming message is an RSTACK + If A && C && !SYNSENT + Reset the link + Else Discard the message + Else the following State Tables. + + o State synchronization across a link is considered to be achieved + when the protocol reaches the ESTAB state. + + State Tables + +State: SYNSENT + ++======================================================================+ +| Condition | Action | New State | ++====================+=====================================+===========+ +| SYNACK && C | Update Peer Verifier; Send ACK | ESTAB | ++--------------------+-------------------------------------+-----------+ +| SYNACK && !C | Send RSTACK | SYNSENT | ++--------------------+-------------------------------------+-----------+ +| SYN | Update Peer Verifier; Send SYNACK | SYNRCVD | ++--------------------+-------------------------------------+-----------+ +| ACK | Send RSTACK | SYNSENT | ++======================================================================+ + + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 40] + +RFC 1987 GSMP Protocol Specification August 1996 + + +State: SYNRCVD + ++======================================================================+ +| Condition | Action | New State | ++====================+=====================================+===========+ +| SYNACK && C | Update Peer Verifier; Send ACK | ESTAB | ++--------------------+-------------------------------------+-----------+ +| SYNACK && !C | Send RSTACK | SYNRCVD | ++--------------------+-------------------------------------+-----------+ +| SYN | Update Peer Verifier; Send SYNACK | SYNRCVD | ++--------------------+-------------------------------------+-----------+ +| ACK && B && C | Send ACK | ESTAB | ++--------------------+-------------------------------------+-----------+ +| ACK && !(B && C) | Send RSTACK | SYNRCVD | ++======================================================================+ + + +State: ESTAB + ++======================================================================+ +| Condition | Action | New State | ++====================+=====================================+===========+ +| SYN || SYNACK | Send ACK (note 1) | ESTAB | ++--------------------+-------------------------------------+-----------+ +| ACK && B && C | Send ACK (note 1) | ESTAB | ++--------------------+-------------------------------------+-----------+ +| ACK && !(B && C) | Send RSTACK | ESTAB | ++======================================================================+ + + Note 1: No more than one ACK should be sent within any time period of + length defined by the timer. + +9. Failure Response Messages + + A failure response message is formed by returning the request message + that caused the failure with the Result field in the header + indicating failure (Result = 4) and the Code field giving the failure + code. The failure code specifies the reason for the switch being + unable to satisfy the request message. A failure code of 16 is used + for a failure that is specific to the particular request message and + its meaning is defined within the text describing that message. The + following failure codes are defined: + + 1: Unspecified reason not covered by other failure codes. + 2: Invalid request message. + 3: The specified request is not implemented on this switch. + 4: Invalid port session number. + 5: One or more of the specified ports does not exist. + + + +Newman, et. al. Informational [Page 41] + +RFC 1987 GSMP Protocol Specification August 1996 + + + 6: One or more of the specified ports is down. + 7: One or more of the specified VPIs or VCIs is out of range on + one or more of the requested ports. + 8: The specified connection does not exist. + 9: The specified branch does not exist. + 10: A branch belonging to the specified multicast connection is + already established on the specified output port and the + switch cannot support more than a single branch of any + multicast connection on the same output port. + 11: The limit on the maximum number of multicast connections that + the switch can support has been reached. + 12: The limit on the maximum number of branches that the + specified multicast connection can support has been reached. + 13: Unable to assign the requested VPI/VCI value to the requested + branch on the specified multicast connection. + 14: General problem related to the manner in which multicast is + supported by the switch. + 15: Out of resources (e.g. memory exhausted, etc.). + 16: Failure specific to the particular message type. + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 42] + +RFC 1987 GSMP Protocol Specification August 1996 + + +REFERENCES + + [I.361] "B-ISDN ATM Layer Specification," International + Telecommunication Union, ITU-T Recommendation I.361, Mar. + 1993. + + [I.363] "B-ISDN ATM Adaptation Layer (AAL) Specification," + International Telecommunication Union, ITU-T Recommendation + I.363, Mar. 1993. + + [rfc1700] "Assigned Numbers," STD 2, RFC 1700, October 1994. + + [rfc1573] "Evolution of the Interfaces Group of MIB-II," RFC 1573, + January 1994. + + +SECURITY CONSIDERATIONS + + Security issues are not discussed in this document. + + +AUTHORS' ADDRESSES + + + Peter Newman Phone: +1 (415) 846-4603 + Ipsilon Networks, Inc. Email: pn@ipsilon.com + + W. L. Edwards, Chief Scientist Phone: +1 (913) 534 5334 + Sprint Email: texas@sprintcorp.com + + Robert M. Hinden Phone: +1 (415) 846-4604 + Ipsilon Networks, Inc. Email: hinden@ipsilon.com + + Eric Hoffman Phone: +1 (415) 846-4610 + Ipsilon Networks, Inc. Email: hoffman@ipsilon.com + + Fong Ching Liaw Phone: +1 (415) 846-4607 + Ipsilon Networks, Inc. Email: fong@ipsilon.com + + Tom Lyon Phone: +1 (415) 846-4601 + Ipsilon Networks, Inc. Email: pugs@ipsilon.com + + Greg Minshall Phone: +1 (415) 846-4605 + Ipsilon Networks, Inc. Email: minshall@ipsilon.com + + + + + + + +Newman, et. al. Informational [Page 43] + +RFC 1987 GSMP Protocol Specification August 1996 + + +Ipsilon Networks, Inc. is located at: + + 2191 East Bayshore Road + Suite 100 + Palo Alto, CA 94303 + USA + +Sprint is located at: + + Sprint + Sprint Technology Services - Long Distance Division + 9300 Metcalf Avenue + Mailstop KSOPKB0802 + Overland Park, KS 66212-6333 + USA + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +Newman, et. al. Informational [Page 44] + |