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diff --git a/doc/rfc/rfc1354.txt b/doc/rfc/rfc1354.txt new file mode 100644 index 0000000..6251ef0 --- /dev/null +++ b/doc/rfc/rfc1354.txt @@ -0,0 +1,675 @@ + + + + + + +Network Working Group F. Baker +Request For Comments: 1354 ACC + July 1992 + + + IP Forwarding Table MIB + +Status of this Memo + + This RFC specifies an IAB standards track protocol for the Internet + community, and requests discussion and suggestions for improvements. + Please refer to the current edition of the "IAB Official Protocol + Standards" for the standardization state and status of this protocol. + Distribution of this memo is unlimited. + +Abstract + + This memo defines a portion of the Management Information Base (MIB) + for use with network management protocols in TCP/IP-based internets. + In particular, it defines objects for managing routes in the IP + Internet. + + It is proposed that the ipRouteTable defined by MIB-II (RFC 1213) be + deprecated and replaced with this table. This adds the ability to + set or display multi-path routes, and varying routes by network + management policy. + +Table of Contents + + 1. The Network Management Framework ............................ 1 + 2. Objects ..................................................... 2 + 2.1 Format of Definitions ...................................... 2 + 3. Overview .................................................... 3 + 3.1 Structure of MIB ........................................... 3 + 4. Definitions ................................................. 4 + 4.1 IP Forwarding Table ........................................ 4 + 5. Acknowledgements ............................................ 11 + 6. References .................................................. 11 + 7. Security Considerations........................................ 12 + 8. Author's Address............................................... 12 + +1. The Network Management Framework + + The Internet-standard Network Management Framework consists of three + components. They are: + + RFC 1155 which defines the SMI, the mechanisms used for describing + and naming objects for the purpose of management. RFC 1212 defines a + + + +Baker [Page 1] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + more concise description mechanism, which is wholly consistent with + the SMI. + + RFC 1156 which defines MIB-I, the core set of managed objects for the + Internet suite of protocols. RFC 1213 defines MIB-II, an evolution + of MIB-I based on implementation experience and new operational + requirements. + + RFC 1157 which defines the SNMP, the protocol used for network access + to managed objects. + + The Framework permits new objects to be defined for the purpose of + experimentation and evaluation. + +2. Objects + + Managed objects are accessed via a virtual information store, termed + the Management Information Base or MIB. Objects in the MIB are + defined using the subset of Abstract Syntax Notation One (ASN.1) [7] + defined in the SMI. In particular, each object has a name, a syntax, + and an encoding. The name is an object identifier, an + administratively assigned name, which specifies an object type. The + object type together with an object instance serves to uniquely + identify a specific instantiation of the object. For human + convenience, we often use a textual string, termed the OBJECT + DESCRIPTOR, to also refer to the object type. + + The syntax of an object type defines the abstract data structure + corresponding to that object type. The ASN.1 language is used for + this purpose. However, the SMI [3] purposely restricts the ASN.1 + constructs which may be used. These restrictions are explicitly made + for simplicity. + + The encoding of an object type is simply how that object type is + represented using the object type's syntax. Implicitly tied to the + notion of an object type's syntax and encoding is how the object type + is represented when being transmitted on the network. + + The SMI specifies the use of the basic encoding rules of ASN.1 [8], + subject to the additional requirements imposed by the SNMP. + +2.1. Format of Definitions + + Section 4 contains contains the specification of all object types + contained in this MIB module. The object types are defined using the + conventions defined in the SMI, as amended by the extensions + specified in [9]. + + + + +Baker [Page 2] + +RFC 1354 IP Forwarding Table MIB July 1992 + + +3. Overview + +3.1. Structure of MIB + + The IP Forwarding Table is quite analogous to the older ipRoute + Table. The principal differences are: + + (1) It is somewhat re-organized, for aesthetic reasons, + + (2) It has the Next Hop Autonomous System Number, useful + primarily to the administrators of regional networks, + + (3) It is instanced by Policy and Next Hop as well as by + ultimate destination. Thus, multiple multipath routes + can be managed, not just a single route, along with the + circumstances under which the any given route might be + chosen. + +4. Definitions + + RFC1354-MIB DEFINITIONS ::= BEGIN + + IMPORTS + Gauge, IpAddress + FROM RFC1155-SMI + mib-2, ip + FROM RFC1213-MIB + OBJECT-TYPE + FROM RFC-1212; + + -- This MIB module uses the extended OBJECT-TYPE macro as + -- defined in [9]. + ipForward OBJECT IDENTIFIER ::= { ip 24 } + + ipForwardNumber OBJECT-TYPE + SYNTAX Gauge + ACCESS read-only + STATUS mandatory + DESCRIPTION + "The number of current ipForwardTable entries + that are not invalid." + ::= { ipForward 1 } + + + -- IP Forwarding Table + + -- The IP Forwarding Table obsoletes and replaces the ipRoute + -- Table current in MIB-I and MIB-II. It adds knowledge of + + + +Baker [Page 3] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + -- the autonomous system of the next hop, multiple next hop + -- support, and policy routing support. + + + ipForwardTable OBJECT-TYPE + SYNTAX SEQUENCE OF IpForwardEntry + ACCESS not-accessible + STATUS mandatory + DESCRIPTION + "This entity's IP Routing table." + REFERENCE + "RFC 1213 Section 6.6, The IP Group" + ::= { ipForward 2 } + + + ipForwardEntry OBJECT-TYPE + SYNTAX IpForwardEntry + ACCESS not-accessible + STATUS mandatory + DESCRIPTION + "A particular route to a particular destina- + tion, under a particular policy." + INDEX { + ipForwardDest, + ipForwardProto, + ipForwardPolicy, + ipForwardNextHop + } + ::= { ipForwardTable 1 } + + + IpForwardEntry ::= + SEQUENCE { + ipForwardDest + IpAddress, + ipForwardMask + IpAddress, + ipForwardPolicy + INTEGER, + ipForwardNextHop + IpAddress, + ipForwardIfIndex + INTEGER, + ipForwardType + INTEGER, + ipForwardProto + INTEGER, + ipForwardAge + + + +Baker [Page 4] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + INTEGER, + ipForwardInfo + OBJECT IDENTIFIER, + ipForwardNextHopAS + INTEGER, + ipForwardMetric1 + INTEGER, + ipForwardMetric2 + INTEGER, + ipForwardMetric3 + INTEGER, + ipForwardMetric4 + INTEGER, + ipForwardMetric5 + INTEGER + } + + ipForwardDest OBJECT-TYPE + SYNTAX IpAddress + ACCESS read-only + STATUS mandatory + DESCRIPTION + "The destination IP address of this route. An + entry with a value of 0.0.0.0 is considered a + default route. + + This object may not take a Multicast (Class D) + address value. + + Any assignment (implicit or otherwise) of an + instance of this object to a value x must be + rejected if the bitwise logical-AND of x with + the value of the corresponding instance of the + ipForwardMask object is not equal to x." + ::= { ipForwardEntry 1 } + + + ipForwardMask OBJECT-TYPE + SYNTAX IpAddress + ACCESS read-write + STATUS mandatory + DESCRIPTION + "Indicate the mask to be logical-ANDed with the + destination address before being compared to + the value in the ipForwardDest field. For + those systems that do not support arbitrary + subnet masks, an agent constructs the value of + the ipForwardMask by reference to the IP Ad- + + + +Baker [Page 5] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + dress Class. + + Any assignment (implicit or otherwise) of an + instance of this object to a value x must be + rejected if the bitwise logical-AND of x with + the value of the corresponding instance of the + ipForwardDest object is not equal to ipForward- + Dest." + DEFVAL { '00000000'h } -- 0.0.0.0 + ::= { ipForwardEntry 2 } + + + -- The following convention is included for specification + -- of TOS Field contents. At this time, the Host Requirements + -- and the Router Requirements documents disagree on the width + -- of the TOS field. This mapping describes the Router + -- Requirements mapping, and leaves room to widen the TOS field + -- without impact to fielded systems. + + ipForwardPolicy OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-only + STATUS mandatory + DESCRIPTION + "The general set of conditions that would cause + the selection of one multipath route (set of + next hops for a given destination) is referred + to as 'policy'. + + Unless the mechanism indicated by ipForwardPro- + to specifies otherwise, the policy specifier is + the IP TOS Field. The encoding of IP TOS is as + specified by the following convention. Zero + indicates the default path if no more specific + policy applies. + + +-----+-----+-----+-----+-----+-----+-----+-----+ + | | | | + | PRECEDENCE | TYPE OF SERVICE | 0 | + | | | | + +-----+-----+-----+-----+-----+-----+-----+-----+ + + IP TOS IP TOS + Field Policy Field Policy + Contents Code Contents Code + 0 0 0 0 ==> 0 0 0 0 1 ==> 2 + 0 0 1 0 ==> 4 0 0 1 1 ==> 6 + 0 1 0 0 ==> 8 0 1 0 1 ==> 10 + + + +Baker [Page 6] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + 0 1 1 0 ==> 12 0 1 1 1 ==> 14 + 1 0 0 0 ==> 16 1 0 0 1 ==> 18 + 1 0 1 0 ==> 20 1 0 1 1 ==> 22 + 1 1 0 0 ==> 24 1 1 0 1 ==> 26 + 1 1 1 0 ==> 28 1 1 1 1 ==> 30 + + Protocols defining 'policy' otherwise must ei- + ther define a set of values which are valid for + this object or must implement an integer- + instanced policy table for which this object's + value acts as an index." + ::= { ipForwardEntry 3 } + + + ipForwardNextHop OBJECT-TYPE + SYNTAX IpAddress + ACCESS read-only + STATUS mandatory + DESCRIPTION + "On remote routes, the address of the next sys- + tem en route; Otherwise, 0.0.0.0." + ::= { ipForwardEntry 4 } + + + ipForwardIfIndex OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-write + STATUS mandatory + DESCRIPTION + "The ifIndex value which identifies the local + interface through which the next hop of this + route should be reached." + DEFVAL { 0 } + ::= { ipForwardEntry 5 } + + + ipForwardType OBJECT-TYPE + SYNTAX INTEGER { + other (1), -- not specified by this MIB + invalid (2), -- logically deleted + local (3), -- local interface + remote (4) -- remote destination + } + ACCESS read-write + STATUS mandatory + DESCRIPTION + "The type of route. Note that local(3) refers + to a route for which the next hop is the final + + + +Baker [Page 7] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + destination; remote(4) refers to a route for + which the next hop is not the final destina- + tion. + + Setting this object to the value invalid(2) has + the effect of invalidating the corresponding + entry in the ipForwardTable object. That is, + it effectively disassociates the destination + identified with said entry from the route iden- + tified with said entry. It is an + implementation-specific matter as to whether + the agent removes an invalidated entry from the + table. Accordingly, management stations must + be prepared to receive tabular information from + agents that corresponds to entries not current- + ly in use. Proper interpretation of such en- + tries requires examination of the relevant ip- + ForwardType object." + DEFVAL { invalid } + ::= { ipForwardEntry 6 } + + ipForwardProto OBJECT-TYPE + SYNTAX INTEGER { + other (1), -- not specified + local (2), -- local interface + netmgmt (3), -- static route + icmp (4), -- result of ICMP Redirect + + -- the following are all dynamic + -- routing protocols + egp (5), -- Exterior Gateway Protocol + ggp (6), -- Gateway-Gateway Protocol + hello (7), -- FuzzBall HelloSpeak + rip (8), -- Berkeley RIP or RIP-II + is-is (9), -- Dual IS-IS + es-is (10), -- ISO 9542 + ciscoIgrp (11), -- Cisco IGRP + bbnSpfIgp (12), -- BBN SPF IGP + ospf (13), -- Open Shortest Path First + bgp (14), -- Border Gateway Protocol + idpr (15) -- InterDomain Policy Routing + } + ACCESS read-only + STATUS mandatory + DESCRIPTION + "The routing mechanism via which this route was + learned. Inclusion of values for gateway rout- + ing protocols is not intended to imply that + + + +Baker [Page 8] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + hosts should support those protocols." + ::= { ipForwardEntry 7 } + + + ipForwardAge OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-only + STATUS mandatory + DESCRIPTION + "The number of seconds since this route was + last updated or otherwise determined to be + correct. Note that no semantics of `too old' + can be implied except through knowledge of the + routing protocol by which the route was + learned." + DEFVAL { 0 } + ::= { ipForwardEntry 8 } + + + ipForwardInfo OBJECT-TYPE + SYNTAX OBJECT IDENTIFIER + ACCESS read-write + STATUS mandatory + DESCRIPTION + "A reference to MIB definitions specific to the + particular routing protocol which is responsi- + ble for this route, as determined by the value + specified in the route's ipForwardProto value. + If this information is not present, its value + should be set to the OBJECT IDENTIFIER { 0 0 }, + which is a syntactically valid object identif- + ier, and any implementation conforming to ASN.1 + and the Basic Encoding Rules must be able to + generate and recognize this value." + DEFVAL { { 0 0 } } -- 0.0 + ::= { ipForwardEntry 9 } + + + ipForwardNextHopAS OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-write + STATUS mandatory + DESCRIPTION + "The Autonomous System Number of the Next Hop. + When this is unknown or not relevant to the + protocol indicated by ipForwardProto, zero." + DEFVAL { 0 } + ::= { ipForwardEntry 10 } + + + +Baker [Page 9] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + ipForwardMetric1 OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-write + STATUS mandatory + DESCRIPTION + "The primary routing metric for this route. + The semantics of this metric are determined by + the routing-protocol specified in the route's + ipForwardProto value. If this metric is not + used, its value should be set to -1." + DEFVAL { -1 } + ::= { ipForwardEntry 11 } + + + ipForwardMetric2 OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-write + STATUS mandatory + DESCRIPTION + "An alternate routing metric for this route. + The semantics of this metric are determined by + the routing-protocol specified in the route's + ipForwardProto value. If this metric is not + used, its value should be set to -1." + DEFVAL { -1 } + ::= { ipForwardEntry 12 } + + + ipForwardMetric3 OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-write + STATUS mandatory + DESCRIPTION + "An alternate routing metric for this route. + The semantics of this metric are determined by + the routing-protocol specified in the route's + ipForwardProto value. If this metric is not + used, its value should be set to -1." + DEFVAL { -1 } + ::= { ipForwardEntry 13 } + + + ipForwardMetric4 OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-write + STATUS mandatory + DESCRIPTION + "An alternate routing metric for this route. + + + +Baker [Page 10] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + The semantics of this metric are determined by + the routing-protocol specified in the route's + ipForwardProto value. If this metric is not + used, its value should be set to -1." + DEFVAL { -1 } + ::= { ipForwardEntry 14 } + + + ipForwardMetric5 OBJECT-TYPE + SYNTAX INTEGER + ACCESS read-write + STATUS mandatory + DESCRIPTION + "An alternate routing metric for this route. + The semantics of this metric are determined by + the routing-protocol specified in the route's + ipForwardProto value. If this metric is not + used, its value should be set to -1." + DEFVAL { -1 } + ::= { ipForwardEntry 15 } + + END + +5. Acknowledgements + + This document was produced by the Router Requirements Working Group, + of which Phil Almquist is the chair. + + Chris Gunner (DEC) and Keith McCloghrie (Hughes LAN Systems) made + significant comments on it, and it is better for their input. + +6. References + + [1] Cerf, V., "IAB Recommendations for the Development of Internet + Network Management Standards", RFC 1052, NRI, April 1988. + + [2] Cerf, V., "Report of the Second Ad Hoc Network Management Review + Group", RFC 1109, NRI, August 1989. + + [3] Rose M., and K. McCloghrie, "Structure and Identification of + Management Information for TCP/IP-based internets", RFC 1155, + Performance Systems International, Hughes LAN Systems, May 1990. + + [4] McCloghrie K., and M. Rose, "Management Information Base for + Network Management of TCP/IP-based internets", RFC 1156, Hughes + LAN Systems, Performance Systems International, May 1990. + + + + + +Baker [Page 11] + +RFC 1354 IP Forwarding Table MIB July 1992 + + + [5] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple + Network Management Protocol", RFC 1157, SNMP Research, + Performance Systems International, Performance Systems + International, MIT Laboratory for Computer Science, May 1990. + + [6] McCloghrie K., and M. Rose, Editors, "Management Information + Base for Network Management of TCP/IP-based internets", RFC + 1213, Performance Systems International, March 1991. + + [7] Information processing systems - Open Systems Interconnection - + Specification of Abstract Syntax Notation One (ASN.1), + International Organization for Standardization, International + Standard 8824, December 1987. + + [8] Information processing systems - Open Systems Interconnection - + Specification of Basic Encoding Rules for Abstract Notation One + (ASN.1), International Organization for Standardization, + International Standard 8825, December 1987. + + [9] Rose, M., and K. McCloghrie, Editors, "Concise MIB Definitions", + RFC 1212, Performance Systems International, Hughes LAN Systems, + March 1991. + + [10] McCloghrie K., and M. Rose, Editors, "Management Information + Base for Network Management of TCP/IP-based internets", RFC + 1213, Performance Systems International, March 1991. + + [11] Baker, F., and R. Coltun, "OSPF Version 2 Management Information + Base", RFC 1253, ACC, Computer Science Center, August 1991. + +7. Security Considerations + + Security issues are not discussed in this memo. + +8. Author's Address + + Fred Baker + Advanced Computer Communications + 315 Bollay Drive + Santa Barbara, CA 93117-6014 + + Phone: (805) 685-4455 + + EMail: fbaker@acc.com + + + + + + + +Baker [Page 12] +
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