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diff --git a/doc/rfc/rfc2340.txt b/doc/rfc/rfc2340.txt new file mode 100644 index 0000000..468ceb3 --- /dev/null +++ b/doc/rfc/rfc2340.txt @@ -0,0 +1,787 @@ + + + + + + +Network Working Group B. Jamoussi +Request for Comments: 2340 D. Jamieson +Category: Informational D. Williston + S. Gabe + Nortel (Northern Telecom) Ltd. + May 1998 + + + Nortel's Virtual Network Switching (VNS) Overview + +Status of this Memo + + This memo provides information for the Internet community. It does + not specify an Internet standard of any kind. Distribution of this + memo is unlimited. + +Copyright Notice + + Copyright (C) The Internet Society (1998). All Rights Reserved. + +Abstract + + This document provides an overview of Virtual Network Switching + (VNS). + + VNS is a multi-protocol switching architecture that provides COS- + sensitive packet switching, reduces the complexity of operating + protocols like PPP and frame relay, provides logical networks and + traffic segregation for Virtual Private Networks (VPNs), security and + traffic engineering, enables efficient WAN broadcasting and + multicasting, and reduces address space requirements. VNS reduces the + number of routing hops over the WAN by switching packets based on + labels. + + VNS has been proven in production networks for several years. + +Table of Contents + + 1 Introduction ............................................ 2 + 2 What is VNS? ............................................ 3 + 3 VNS Header ............................................. 5 + 4 VNS Label Distribution .................................. 7 + 5 Logical Networks (LNs) .................................... 7 + 6 VNS Routing ............................................. 8 + 7 VNS Forwarding .......................................... 9 + 7.1 Unicast ................................................ 9 + 7.2 Multicast .............................................. 9 + 8 Traffic Engineering ..................................... 10 + + + +Jamoussi, et. al. Informational [Page 1] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + + 8.1 Equal Cost Multipaths .................................. 10 + 8.2 Trunk Load Spreading ................................... 10 + 9 Class of Service ........................................ 11 + 10 VNS Migration Strategies ................................ 11 + 11 Summary ................................................. 11 + 12 Security Considerations ................................. 12 + 13 Acknowledgments ......................................... 12 + 14 Authors' Addresses ...................................... 13 + 15 Full Copyright Statement ................................ 14 + +1. Introduction + + There are several key problem areas with today's wide area backbone + networks that carry LAN traffic: scalability, service + differentiation, redundancy, administration, and traffic containment. + + First, scalability is becoming a major concern because of the rapid + growth in bandwidth demand and geographical reach. As the size of the + WAN network grows traditional point-to-point and NBMA topologies or + network models lose their performance. + + Second, the need to provide several Classes of Service (CoS) has + never been greater. The days of a single "best effort" service are + over and service providers demand ways to differentiate the quality + of the service offered to their clients based on several policies. + + Third, the WAN is often carrying mission-critical traffic and loss of + service is not acceptable. So far, path redundancy has been addressed + inefficiently by requiring additional links or VCs. + + Fourth, network operators demand easy and simplified network + administration. Large NBMA topologies require extensive PVC + provisioning until SVC deployment becomes more ubiquitous. For + Point-to-point models, IP address space may be used inefficiently and + non-trivial network schemas are required to contain reserved address + space. + + Finally, proper segregation of traffic is becoming a must. This + requirement is being addressed today by adding leased lines or VCs + used to separate traffic flows based on regions or interest or + protocol. + + Nortel's Virtual Network Switching (VNS) is a technology that + provides efficient solutions to these challenges. + + + + + + + +Jamoussi, et. al. Informational [Page 2] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + + Section 2 provides an overview of VNS. The VNS header is specified in + Section 3. Section 4 describes the VNS label distribution mechanism. + Section 5 defines how a VNS network can be partitioned into Logical + Networks (LN). Section 6 outlines VNS routing. Section 7 defines both + unicast and multicast forwarding. Section 8 describes the mechanisms + used to engineer the traffic. Section 9 defines the COS based + switching of VNS. Section 10 provides network migration scenarios + using VNS. A summary of VNS is provided in Section 11. + +2. What is VNS? + + Virtual Network Switching (VNS) is a CoS-sensitive multi-protocol + label switching architecture that reduces or eliminates the number of + layer 3 hops over the WAN by switching traffic based on labels. + + VNS makes a network of point to point links appear to be a single + LAN (broadcast, multiple access) media. The network used by a + particular instance of VNS is called a Logical Network (LN) which is + described in more detail in Section 5. + + In reference to the ISO Network Layering Model, the Data Link Layer + is expanded to include VNS network layer. To the ISO Network Layer, + (e.g., IP), VNS is treated as a Data Link Layer. + + ------------------------ + | Application | + ------------------------ + | Presentation | + ------------------------ + | Session | + ------------------------ + | Transport | + ------------------------ ------------------------- + | Network (e.g., IP) | / Network VNS | + ----------------------------- | + | Data Link |-------------------------- + ----------------------------- | + | Physical | \ data link (e.g., ATM) | + ------------------------ ------------------------- + + Figure 1. ISO Network Layering Model for VNS + + In a VNS Network, three separate nodal functions are defined. An + ingress node, an egress node, and a tandem node. The ingress and + egress nodes define the boundary between an IP network and the VNS + network. Therefore, these nodes run both IP routing and VNS routing. + However, tandem nodes need only run VNS routing. + + + + +Jamoussi, et. al. Informational [Page 3] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + + A LAN packet is encapsulated in a VNS header as it enters the LN. The + label in the header is used to switch the packet across the LN. The + encapsulation header contains the identifier of the last node (or + egress node) that processes the packet as it traverses the LN. It is + the first node (or ingress node) that decides to which egress node + the packet is sent. All nodes between the ingress and egress nodes + (known as tandem nodes) decide independently the best packet + forwarding route to the egress node identified in the packet. + + The network layer protocols view VNS as a shared broadcast media, + where the speed to reach any node on the media is the same for all + nodes. VNS ensures that traffic destined to other nodes is forwarded + optimally. This transparent view of the VNS means that all the + details of the network (for example, topology and link states) can be + hidden from the Upper Layer Protocols (e.g. Layer 3 routing + protocols) and their applications. VNS also ensures that changes to + topology and link state are hidden. + + The network layer protocol on the ingress node views the network + layer protocol on the egress node as its logical and directly + connected neighbor. This is significant because the network layer + protocols always decide which directly connected neighbor should + receive a forwarded packet. The details of the actual topology + supporting the connectionless network are managed entirely by the + Virtual Network Switching and are hidden from the network layer + protocols. To the network layer, VNS simply appears to be another + Data Link Layer (or media), even though VNS is a network layer itself + running on top of the actual Data Link Layer (for example, ATM + trunks). + + For the ingress node to choose the egress node that provides the best + path to the packet's final destination, it must have knowledge of the + following: + + - the nodes that can be reached in the network + - the topology of the network that is using the VNS services for + transport across the network (but not necessarily the topology + of the full network) + + This knowledge is obtained through the network layer routing + mechanisms such as, IP's Open Shortest Path First (OSPF) and Address + Resolution Protocol (ARP). + + Once the network layer protocol on the ingress node has decided which + neighbor to transmit the packet to, it is the responsibility of VNS + forwarding, a part of VNS, to deliver the packet to that node. Once + the packet arrives at the egress node, the packet is delivered to the + network layer protocol, which then forwards it to its ultimate + + + +Jamoussi, et. al. Informational [Page 4] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + + destination. + + Tandem nodes have no interaction with the network layer protocols. + They only require knowledge of the VNS network topology. They make + their packet forwarding decision on the egress node identifier and + LN identifier carried in the VNS header of the packet. + +3. VNS Header + + VNS defines a unicast header shown in Figure 2 and a multicast header + shown in Figure 3. + + 3 2 1 0 + 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | TTL | LNN |x|LS-Key |x|DP | CmnHdr | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Protocol Type | Destination Node Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | COS |x x x x| Source Node Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Network Layer Header (e.g. IP) | + / / + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Data | + / / + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Figure 2. Unicast VNS Header + + The unicast header includes the following fields: + + - Common Header (CmnHdr): The common header identifies the packet to + be a VNS encapsulated packet. + + - Discard Priority: Indicates the level of congestion at which the + packet should be discarded. The value of this field is assigned on + the originating node based on policy information (see Section 9). + + - Load Spreading Key: indicates the stream to which the packet + belongs for the purposes of equal cost multipath and trunk load + spreading (see Section 8). + + - LNN: The Logical Network Number defines the logical network the + packet belongs to. This field in is used in conjunction with the + destination node identifier as the VNS switching label (see Section + 5). + + + + +Jamoussi, et. al. Informational [Page 5] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + + - TTL: The Time To Live field is used to detect and discard packets + caught in temporary routing loops. + + - Destination Node Identifier: This field contains an ID which + uniquely identifies the destination node. This ID is unique to the + physical network not just the LN. In conjunction with the LNN, this + forms a global VNS switching label. + + - Protocol Type: indicates the type of Network layer protocol being + carried in the packet. Examples include IP, IPX, and Bridging. If the + packet is a multicast packet then this is indicated in this field. + + - Source Node Identifier: This field contains an ID which uniquely + identifies the source node (ingress node). + + - CoS: The Class of Service field is used to provide routing class of + service. The COS field also affects the Emission Priority of the + packet in the scheduler (see Section 9). + + - Reserved Fields: All the fields marked with "x" are Reserved. + + 3 2 1 0 + 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | TTL | LNN |x|LS-Key |x|DP | CmnHdr | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | PT = Multicast| Destination Node Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | COS |x x x x| Source Node Identifier | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Protocol Type |x x x x x x x x| Multicast Group | + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + | Network Layer Header (e.g. IP) | + / / + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + / Data / + +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ + + Figure 3. Multicast VNS Header + + The multicast header shown in Figure 3, includes all the fields of + the unicast header. In addition, the multicast header includes the + following fields: + + - Multicast Group: this field is used to identify a sub-group within + the logical network that receives the multicast packets. + + + + + +Jamoussi, et. al. Informational [Page 6] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + + - Protocol Type: indicates the type of Network layer protocol being + carried in the packet. Examples include IP, IPX, and Bridging. + +4. VNS Label Distribution + + Label distribution in VNS is based on a distributed serverless + topology driven approach. Standard ARP or address gleaning is used to + distribute and map network layer addresses to VNS addresses. + + A VNS Label is an 6 byte encoding of the LNN and the node ID. VNS + Labels are treated as MAC addresses by the network layer. This means + that labels are distributed by the same means network layers use to + distribute MAC addresses. Thus, VNS leverages existing L2/L3 mapping + techniques and doesn't require a separate Label Distribution + Protocol. + +5. Logical Networks (LNs) + + A logical network consists of a subset of the nodes in a network + together with a subset of the trunking facilities that link those + nodes. Logical networks partition the network into subnetworks that + serve a subset of the overall topology. + + Each of the logical networks supported on any given node has a + separate routing and forwarding table (built by VNS). Therefore, + routing decisions are based on the resources available to the logical + network, not the entire network. + + Each instance of VNS will discover all the trunks which are connected + to neighbors which support a matching LNN. This provides a huge + administrative saving, since VNS provisioning is on a per-node basis, + not on a per-link basis. VNS provisioning requires only a unique + node ID and an LNN. Discovery of which trunks support which LNNs is + done at run time, relieving administrative effort, and allowing the + LN to dynamically adapt to topology changes. + + Multiple Logical Networks provide the following benefits to the + network system: + + - Logical networks allow service providers to service multiple + private networks or (Virtual Private Internets) easily over one + network. + + - Logical networks can be used to limit the impact of one network + layer protocol on the others. This is particularly true for + protocols that broadcast or multicast a large percentage of either + their control or data packets. This increases the effective + bandwidth of the trunks and allows the overall network to scale + + + +Jamoussi, et. al. Informational [Page 7] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + + better. + + - Logical networks allow for the configuration of the network to + meet individual community of interest and geographical + subnetworking needs. + + - Routing control traffic has significance only in the local + subnetwork that is isolated to that subnetwork. + + - Logical networks allow different instances of the same protocol + to share trunk facilities. + +6. VNS Routing + + VNS routing is a link state routing system which uses many concepts + similar to OSPF and PNNI. One of the most significant departures from + the others is its ability to calculate shortest path trees for + routing unicast traffic and spanning trees for routing multicast + traffic within a Logical Network. + + There is only one type of interface that VNS routing supports and + this is known as a VNS link. A link is a set of trunks that join two + VNS neighbor nodes. Each node in a VNS network maintains information + about the state of locally attached links. This information is + flooded throughout the network whenever there is a significant change + to the link's state or attributes (i.e. up/down, speed change, + available bandwidth change). + + Each node stores and forwards the link state information received + from all other nodes. This allows each node to have the same view of + all of the nodes in the network together with all of their link state + information. This data is used to compute both the shortest path to + reach each node in the Logical Network and a spanning tree for the + Logical Network. + + Logical networks are not bound to a particular trunk or link. They + are configured on a node. By default, a link will support a specific + logical network if the two nodes which it connects both are + configured to support the logical network number. This provides a + significant savings in operations over having to configure logical + networks on links or trunks. + + When a link first comes into service, a protocol is run which allows + the two neighboring nodes to exchange information about the logical + networks they support. This allows the two nodes to determine if the + links are to be considered as a locally attached link for a logical + network. + + + + +Jamoussi, et. al. Informational [Page 8] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + +7. VNS Forwarding + + VNS supports two types of forwarding: unicasting and multicasting. In + the first type, the data packet arrives on the ingress node and + unicasting forwards the data packet to a single destination (egress + node). In the second type, the data packet arrives on the ingress + node and multicasting forwards the data packet to all other nodes in + the logical network. + +7.1 Unicast + + When a packet first enters the LAN internetwork, the network layer + routing protocol determines the next hop of the best route for the + packet to reach its final destination. If the best route is through a + VNS Logical Network, the network layer routing protocol relies on VNS + forwarding to get the packet to the egress node. A VNS packet header + containing the node ID (the unique ID assigned to each node) of the + egress node is added to the front of the packet and VNS forwarding is + invoked to deliver the packet. The network layer routing protocol + learns the egress node ID through an Address Resolution Protocol + (ARP) for IP and Source Address learning for bridging. + + As the packet traverses the LN, routing decisions are made to + determine the next hop in the route to reach the destination node ID + specified in the VNS header. A forwarding table is built on each node + that assists in making the routing decision. + + Each VNS instance on each node builds and maintains a forwarding + table for its LN. Each forwarding table has an entry for every node + that is a member of the logical network. + +7.2 Multicast + + In addition to the unicast forwarding function, VNS also supports a + multicast forwarding service for traffic within an LN at the VNS + layer. Multicast packets are delivered to all nodes supporting the + logical network to which the multicast packet belongs. The packets + are sent along the branches of a spanning tree that is built by each + node supporting the logical network and is based on a common root + node (so that each node's view of the tree is the same as other + nodes). In other words, multicast packets are sent intelligently, + consuming a minimum of network bandwidth. If the network topology is + stable, each node receives each multicast packet only once. + + Multicast packets received at any node are not acknowledged. They are + simply forwarded to the specified network layer interface and sent to + any other neighbor nodes on the spanning tree. + + + + +Jamoussi, et. al. Informational [Page 9] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + +8. Traffic Engineering + + VNS forwarding supports two types of traffic engineering mechanisms: + equal cost multipaths and trunk load spreading. + + Equal cost multipaths allows different streams (unique network layer + source and destination address pairings) to be load spread between + multiple relatively equal cost paths, through the Logical Network to + the egress node. + + Trunk load spreading between two neighbors can take place when + multiple VNS trunks are defined between neighbors. Again, the load + spreading is based on network layer streams. + +8.1 Equal Cost Multipaths + + From any point in a logical network, there may be multiple paths to + reach a specific egress node. If VNS routing determines that more + than one of these paths are of equal cost, VNS packets will be load + spread between two of them. + + Equal cost multipath forwarding is supported not only on ingress + nodes but on tandem nodes as well. Each packet on an ingress node is + tagged with an equal cost multipath key. This key is acted upon at + the ingress node and stored in the VNS header to be used on tandem + nodes. + + The equal cost multipath key is calculated by running an algorithm + over the source and destination network layer addresses. This means + that, in a stable network, any given stream will always take the same + path through a Logical Network avoiding the problems that misordering + would otherwise cause. + +8.2 Trunk Load Spreading Between Neighbors + + VNS allows multiple trunks to be configured between neighboring VNS + nodes. VNS routing considers the aggregate bandwidth of those trunks + to determine the metric between the nodes. Also, VNS load spreads its + traffic amongst those trunks. + + As is the case with equal cost multipaths, the trunk load spreading + key is calculated on the ingress node from an algorithm run over the + source and destination network layer addresses. The key is then + stored in the VNS header to be used on all tandem nodes through the + Logical Network. + + + + + + +Jamoussi, et. al. Informational [Page 10] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + +9. Class of Service + + At the ingress to a VNS Network, packets are classified according to + the Class of Service (Cos) policy settings. The CoS differentiation + is achieved through different Emission and Discard priorities. The + semantics of the classification is carried in the VNS label (DP and + COS Fields described in Section 3) to be used at the ingress node as + well as all tandem points in the VNS network to affect queuing and + scheduling decisions. + +10. VNS Migration Strategies + + VNS supports several upper layer protocols such as IP, IPX, and + Bridging. Therefore, it is a multiprotocol label switching + architecture. In addition, VNS is not tied to a particular L2 + technology. It runs on cell (e.g., ATM) trunks, frame trunks, or a + mixture of both. + + VNS can be gradually introduced in a network. It can be implemented + between switching elements interconnected by point to point links. + Each of the switching nodes can run layer 3 routing simultaneously + with packet switching. VNS also allows for the interconnection of VNS + clouds through an ATM VC. + + Since VNS can run on a mixture of Frame and Cell trunks, it allows + for the graceful migration of the frame links to ATM without + requiring a complete immediate overhaul. + +11. Summary + + VNS addresses scalability problems in several ways: + + 1. By a generally distributed design which doesn't + require a Label Distribution Protocol, or servers of any kind. + 2. By providing an efficient, distributed multicast mechanism. + 3. By allowing administrators to control the size of a + Logical Network, limiting traffic to a subset of the physical + topology. + 4. By reducing layer 3 address space/subnet requirements in the + WAN which reduces the routing table size. + + VNS provides redundancy transparent to the network layer protocol by + managing the network of trunks independently of the network layer. + VNS will automatically discover any topology changes and re-route + traffic accordingly. + + + + + + +Jamoussi, et. al. Informational [Page 11] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + + VNS eases network administration by dynamically keeping track of + which trunks are available for each LNN. Network administrators + don't have to configure VNS or network layer addresses on a per link + basis. Network layer addresses only have to be assigned on a per + Logical Network basis. For nodes which will only be tandem VNS + nodes, network layer addresses aren't required at all. + + Since VNS traffic is constrained within an LNN, administrators have + control of where VNS traffic is allowed to flow. + + Finally, VNS supports switching of several Upper Layer Protocols and + supports several media (cell and Frame) or a mixture thereof. + Switching in the core of the WAN removes the need for routers and + improves the performance due to a reduction in the number of fields + that need to processed. + +12. Security Considerations + + Logical networks provide a means of restricting traffic flow for + security purposes. VNS also relies on the inherent security of the L2 + media such as an ATM Virtual Circuit. + +13. Acknowledgments + + The authors would like to acknowledge the valuable comments of Terry + Boland, Pierre Cousineau, Robert Eros, Robert Tomkins, and John + Whatman. + + + + + + + + + + + + + + + + + + + + + + + + +Jamoussi, et. al. Informational [Page 12] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + +14. Authors' Addresses + + Bilel Jamoussi + Nortel (Northern Telecom), Ltd. + PO Box 3511 Station C + Ottawa ON K1Y 4H7 + Canada + + EMail: jamoussi@Nortel.ca + + + Dwight Jamieson + Nortel (Northern Telecom), Ltd. + PO Box 3511 Station C + Ottawa ON K1Y 4H7 + Canada + + EMail: djamies@Nortel.ca + + + Dan Williston + Nortel (Northern Telecom), Ltd. + PO Box 3511 Station C + Ottawa ON K1Y 4H7 + Canada + + EMail: danwil@Nortel.ca + + + Stephen Gabe + Nortel (Northern Telecom), Ltd. + PO Box 3511 Station C + Ottawa ON K1Y 4H7 + Canada + + EMail: spgabe@Nortel.ca + + + + + + + + + + + + + + + +Jamoussi, et. al. Informational [Page 13] + +RFC 2340 Nortel's Virtual Network Switching (VNS) May 1998 + + +15. Full Copyright Statement + + Copyright (C) The Internet Society (1998). All Rights Reserved. + + This document and translations of it may be copied and furnished to + others, and derivative works that comment on or otherwise explain it + or assist in its implementation may be prepared, copied, published + and distributed, in whole or in part, without restriction of any + kind, provided that the above copyright notice and this paragraph are + included on all such copies and derivative works. However, this + document itself may not be modified in any way, such as by removing + the copyright notice or references to the Internet Society or other + Internet organizations, except as needed for the purpose of + developing Internet standards in which case the procedures for + copyrights defined in the Internet Standards process must be + followed, or as required to translate it into languages other than + English. + + The limited permissions granted above are perpetual and will not be + revoked by the Internet Society or its successors or assigns. + + This document and the information contained herein is provided on an + "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING + TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING + BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION + HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF + MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. + + + + + + + + + + + + + + + + + + + + + + + + +Jamoussi, et. al. Informational [Page 14] + |