Network Working Group D. Cansever
Request for Comments: 2333 GTE Laboratories, Inc.
Category: Standards Track April 1998
Network Working Group D. Cansever
Request for Comments: 2333 GTE Laboratories, Inc.
Category: Standards Track April 1998
NHRP Protocol Applicability Statement
NHRP协议适用性声明
Status of this Memo
本备忘录的状况
This document specifies an Internet standards track protocol for the Internet community, and requests discussion and suggestions for improvements. Please refer to the current edition of the "Internet Official Protocol Standards" (STD 1) for the standardization state and status of this protocol. Distribution of this memo is unlimited.
本文件规定了互联网社区的互联网标准跟踪协议，并要求进行讨论和提出改进建议。有关本协议的标准化状态和状态，请参考当前版本的“互联网官方协议标准”（STD 1）。本备忘录的分发不受限制。
Copyright Notice
版权公告
Copyright (C) The Internet Society (1998). All Rights Reserved.
版权所有（C）互联网协会（1998年）。版权所有。
Abstract
摘要
As required by the Routing Protocol Criteria [RFC 1264], this memo discusses the applicability of the Next Hop Resolution Protocol (NHRP) in routing of IP datagrams over Non-Broadcast Multiple Access (NBMA) networks, such as ATM, SMDS and X.25.
根据路由协议标准[RFC 1264]的要求，本备忘录讨论了下一跳解析协议（NHRP）在非广播多址（NBMA）网络（如ATM、SMDS和X.25）上路由IP数据报时的适用性。
The NHRP protocol description is defined in [1]. The NHRP MIB description is defined in [2].
[1]中定义了NHRP协议描述。[2]中定义了NHRP MIB描述。
This document summarizes the key features of NHRP and discusses the environments for which the protocol is well suited. For the purposes of description, NHRP can be considered a generalization of Classical IP and ARP over ATM which is defined in [3] and of the Transmission of IP Datagrams over the SMDS Service, defined in [4]. This generalization occurs in 2 distinct directions.
本文档总结了NHRP的关键特性，并讨论了该协议非常适合的环境。为了便于描述，NHRP可被视为[3]中定义的ATM上的经典IP和ARP以及[4]中定义的SMDS服务上的IP数据报传输的推广。这种概括有两个不同的方向。
Firstly, NHRP avoids the need to go through extra hops of routers when the Source and Destination belong to different Logical Internet Subnets (LIS). Of course, [3] and [4] specify that when the source and destination belong to different LISs, the source station must forward data packets to a router that is a member of multiple LISs, even though the source and destination stations may be on the same logical NBMA network. If the source and destination stations belong to the same logical NBMA network, NHRP provides the source station
首先，当源和目的地属于不同的逻辑Internet子网（LIS）时，NHRP避免了需要经过额外的路由器跳数。当然，[3]和[4]规定，当源站和目的站属于不同的LIS时，源站必须将数据包转发给作为多个LIS成员的路由器，即使源站和目的站可能位于同一逻辑NBMA网络上。如果源站和目的站属于同一逻辑NBMA网络，则NHRP提供源站
with an inter-LIS address resolution mechanism at the end of which both stations can exchange packets without having to use the services of intermediate routers. This feature is also referred to as "short-cut" routing. If the destination station is not part of the logical NBMA network, NHRP provides the source with the NBMA address of the current egress router towards the destination.
具有LIS间地址解析机制，在该机制的末尾，两个站点可以交换数据包，而无需使用中间路由器的服务。此功能也称为“捷径”布线。如果目标站不是逻辑NBMA网络的一部分，则NHRP向源提供朝向目标的当前出口路由器的NBMA地址。
The second generalization is that NHRP is not specific to a particular NBMA technology. Of course, [3] assumes an ATM network and [4] assumes an SMDS network at their respective subnetwork layers.
第二个概括是，NHRP不是特定于特定NBMA技术的。当然，[3]假设ATM网络，[4]假设SMDS网络位于各自的子网络层。
NHRP is specified for resolving the destination NBMA addresses of IP datagrams over IP subnets within a large NBMA cloud. NHRP has been designed to be extensible to network layer protocols other than IP, possibly subject to other network layer protocol specific additions.
指定NHRP用于在大型NBMA云中通过IP子网解析IP数据报的目标NBMA地址。NHRP被设计为可扩展到除IP以外的网络层协议，可能会受到其他网络层协议特定添加的影响。
As an important application of NHRP, the Multiprotocol Over ATM (MPOA) Working Group of the ATM Forum has decided to adopt and to integrate NHRP into its MPOA Protocol specification [5]. As such, NHRP will be used in resolving the ATM addresses of MPOA packets destined outside the originating subnet.
作为NHRP的一个重要应用，ATM论坛的多协议ATM（MPOA）工作组决定采用NHRP并将其集成到其MPOA协议规范中[5]。因此，NHRP将用于解析目的地在发起子网之外的MPOA数据包的ATM地址。
NHRP provides a mechanism to obtain the NBMA network address of the destination, or of a router along the path to the destination. NHRP is not a routing protocol, but may make use of routing information. This is further discussed in Section 5.
NHRP提供了一种机制，用于获取目的地的NBMA网络地址，或沿到目的地的路径获取路由器的NBMA网络地址。NHRP不是路由协议，但可以利用路由信息。这将在第5节中进一步讨论。
The most prominent feature of NHRP is that it avoids extra router hops in an NBMA with multiple LISs. To this goal, NHRP provides the source with the NBMA address of the destination, if the destination is directly attached to the NBMA. If the destination station is not attached to the NBMA, then NHRP provides the source with the NBMA address of an exit router that has connectivity to the destination. In general, there may be multiple exit routers that have connectivity to the destination. If NHRP uses the services of a dynamic routing algorithm in fulfilling its function, which is necessary for robust and scalable operation, then the exit router identified by NHRP reflects the selection made by the network layer dynamic routing protocol. In general, the selection made by the routing protocol would often reflect a desirable attribute, such as identifying the exit router that induces the least number of hops in the original routed path.
NHRP最显著的特点是，它避免了具有多个LIS的NBMA中额外的路由器跳数。为此，如果目的地直接连接到NBMA，则NHRP向源提供目的地的NBMA地址。如果目标站未连接到NBMA，则NHRP向源提供连接到目标的出口路由器的NBMA地址。通常，可能有多个出口路由器连接到目的地。如果NHRP使用动态路由算法的服务来实现其功能，这是稳健和可扩展操作所必需的，那么由NHRP标识的出口路由器反映了网络层动态路由协议所做的选择。通常，路由协议所做的选择通常会反映期望的属性，例如识别在原始路由路径中引起最少跳数的出口路由器。
NHRP is defined for avoiding extra hops in the delivery of IP packets with a single destination. As such, it is not intended for direct use in a point-to-multipoint communication setting. However, elements of NHRP may be used in certain multicast scenarios for the purpose of providing short cut routing. Such an effort is discussed in [6]. In this case, NHRP would avoid intermediate routers in the multicast path. The scalability of providing short-cut paths in a multicast environment is an open issue.
NHRP的定义是为了避免在单一目的地的IP数据包传输中出现额外的跳数。因此，它不打算在点对多点通信设置中直接使用。然而，为了提供快捷路由，可以在某些多播场景中使用NHRP的元素。[6]中讨论了这种努力。在这种情况下，NHRP将避免多播路径中的中间路由器。在多播环境中提供快捷路径的可伸缩性是一个有待解决的问题。
NHRP can be used in host-host, host-router and router-host communications. When used in router-router communication, NHRP (as defined in [1]) can produce persistent routing loops if the underlying routing protocol looses information critical to loop suppression. This may occur when there is a change in router metrics across the autonomous system boundaries. NHRP for router-router communication that avoids persistent forwarding loops will be addressed in a separate document.
NHRP可用于主机、主机路由器和路由器-主机通信。当用于路由器-路由器通信时，如果底层路由协议丢失了对环路抑制至关重要的信息，则NHRP（如[1]中所定义）可以产生持久路由环路。当自治系统边界上的路由器度量发生变化时，可能会发生这种情况。避免持久转发循环的路由器-路由器通信的NHRP将在单独的文档中解决。
A special case of router-router communication where loops will not occur is when the destination host is directly adjacent to the non-NBMA interface of the egress router. If it is believed that the adjacency of the destination station to the egress router is a stable topological configuration, then NHRP can safely be used in this router-router communication scenario. If the NHRP Request has the Q bit set, indicating that the requesting party is a router, and if the destination station is directly adjacent to the egress router as a stable topological configuration, then the egress router can issue a corresponding NHRP reply. If the destination is not adjacent to the egress router, and if Q bit is set in the Request, then a safe mode of operation for the egress router would be to issue a negative NHRP Reply (NAK) for this particular request, thereby enforce data packets to follow the routed path.
路由器通信的一种特殊情况是，当目标主机直接与出口路由器的非NBMA接口相邻时，不会发生环路。如果认为目的站与出口路由器的邻接是稳定的拓扑结构，那么NHRP可以安全地用于此路由器通信场景。如果NHRP请求设置了Q位，指示请求方是路由器，并且如果目的站作为稳定拓扑配置直接与出口路由器相邻，则出口路由器可以发出相应的NHRP应答。如果目的地与出口路由器不相邻，并且如果在请求中设置了Q位，则出口路由器的安全操作模式将是针对该特定请求发出否定NHRP应答（NAK），从而强制数据分组跟随路由路径。
As a result of having inter-LIS address resolution capability, NHRP allows the communicating parties to exchange packets by fully utilizing the particular features of the NBMA network. One such example is the use of QoS guarantees when the NMBA network is ATM.
由于具有LIS间地址解析能力，NHRP允许通信各方通过充分利用NBMA网络的特定特征来交换分组。其中一个例子是当NMBA网络是ATM时使用QoS保证。
Here, due to short-cut routing, ATM provided QoS guarantees can be implemented without having to deal with the issues of re-assembling and re-segmenting IP packets at each network layer hop.
这里，由于采用了捷径路由，可以实现ATM提供的QoS保证，而无需处理在每个网络层跃点处重新组装和重新分割IP数据包的问题。
NHRP protocol can be viewed as a client-server interaction. An NHRP Client is the one who issues an NHRP Request. An NHRP Server is the one who issues a reply to an NHRP request, or the one who forwards a received NHRP request to another Server. Of course, an NHRP entity may act both as a Client and a Server.
NHRP协议可以看作是一种客户机-服务器交互。NHRP客户机是发出NHRP请求的人。NHRP服务器是对NHRP请求发出回复的服务器，或者是将接收到的NHRP请求转发给另一台服务器的服务器。当然，NHRP实体可以同时充当客户端和服务器。
In general, issuing an NHRP request is an application dependent action [7]. For applications that do not have particular QoS requirements, and that are executed within a short period of time, an NBMA short-cut may not be a necessity. In situations where there is a "cost" associated with NBMA short-cuts, such applications may be better served by network layer hop-by-hop routing. Here, "cost" may be understood in a monetary context, or as additional strain on the equipment that implements short-cuts. Therefore, there is a trade-off between the "cost" of a short-cut path and its utility to the user. Reference [7] proposes that this trade-off should be addressed at the application level. In an environment consisting of LANs and routers that are interconnected via dedicated links, the basic routing decision is whether to forward a packet to a router, or to broadcast it locally. Such a decision on local vs. remote is based on the destination address. When routing IP packets over an NBMA network, where there is potentially a direct Source to Destination connectivity with QoS options, the decision on local vs. remote is no longer as fundamentally important as in the case where packets have to traverse routers that are interconnected via dedicated links. Thus, in an NBMA network with QoS options, the basic decision becomes the one of short-cut vs. hop-by-hop network layer routing. In this case, the relevant criterion becomes applications' QoS requirements [7]. NHRP is particularly applicable for environments where the decision on local vs. remote is superseded by the decision on short-cut vs. hop-by-hop network layer routing.
通常，发出NHRP请求是一种依赖于应用程序的操作[7]。对于没有特定QoS要求且在短时间内执行的应用程序，NBMA捷径可能不是必需的。在存在与NBMA捷径相关的“成本”的情况下，网络层逐跳路由可以更好地服务于此类应用。在这里，“成本”可以从货币的角度来理解，也可以理解为对实施捷径的设备造成的额外压力。因此，在一条捷径的“成本”和它对用户的效用之间存在一种权衡。参考文献[7]建议应在应用程序级别解决这一权衡问题。在由局域网和通过专用链路互连的路由器组成的环境中，基本路由决定是将数据包转发到路由器，还是在本地广播。本地与远程的这种决定是基于目标地址的。当通过NBMA网络路由IP数据包时，如果可能存在具有QoS选项的直接源到目的地连接，则本地与远程的决策不再像数据包必须通过通过专用链路互连的路由器那样重要。因此，在具有QoS选项的NBMA网络中，基本决策变成了捷径与逐跳网络层路由。在这种情况下，相关标准成为应用程序的QoS要求[7]。NHRP特别适用于以下环境：本地与远程路由的决定被短途与逐跳网络层路由的决定所取代。
Let us assume that the trade-off is in favor of a short-cut NBMA route. Generally, an NHRP request can be issued by a variety of NHRP aware entities, including hosts and routers with NBMA interfaces. If an IP packet traverses multiple hops before a short-cut path has been established, then there is a chance that multiple short-cut paths could be formed. In order to avoid such an undesirable situation, a useful operation rule is to authorize only the following entities to issue an NHRP request and to perform short-cut routing.
让我们假设这种权衡有利于一条捷径NBMA路线。通常，NHRP请求可以由各种NHRP感知实体发出，包括具有NBMA接口的主机和路由器。如果一个IP包在一条短路径建立之前经过多个跃点，那么就有可能形成多条短路径。为了避免这种不良情况，一个有用的操作规则是仅授权以下实体发出NHRP请求并执行快捷路由。
i) The host that originates the IP packet, if the host has an NBMA interface. ii) The first router along the routing path of the IP packet such that the next hop is reachable through the NBMA interface of that particular router. iii) A policy router within an NBMA network through which the IP packet has to traverse.
i） 如果主机具有NBMA接口，则发起IP数据包的主机。ii）沿IP分组的路由路径的第一路由器，使得下一跳可通过该特定路由器的NBMA接口到达。iii）NBMA网络内的策略路由器，IP数据包必须通过该路由器。
As previously indicated, NHRP is defined for the delivery of IP packets with a single destination. Thus, this discussion is confined to a unicast setting. The scalability of NHRP can be analyzed at three distinct levels:
如前所述，NHRP被定义为具有单个目的地的IP分组的传送。因此，此讨论仅限于单播设置。NHRP的可扩展性可以从三个不同的层次进行分析：
o Client level o LIS level o Domain level
o 客户端级别o LIS级别o域级别
At the the Client level, the scalability of NHRP is affected by the processing and memory limitations of the NIC that provides interface to the NBMA network. When the NBMA network is connection oriented, such as ATM, NIC limitations may bound the scalability of NHRP in certain applications. For example, a server that handles hundreds of requests per second using an ATM interface may be bounded by the performance characteristics of the corresponding NIC. Similarly, when the NHRP Client resides at an NBMA interface of a router, memory and processing limitations of router's NIC may bound the scalability of NHRP. This is because routers generally deal with an aggregation of traffic from multiple sources, which in turn creates a potentially large number of SVCCs out of the router's NBMA interface.
在客户端级别，NHRP的可伸缩性受提供NBMA网络接口的NIC的处理和内存限制的影响。当NBMA网络面向连接时，如ATM，NIC限制可能会限制NHRP在某些应用中的可扩展性。例如，使用ATM接口每秒处理数百个请求的服务器可能受到相应NIC性能特征的限制。类似地，当NHRP客户端驻留在路由器的NBMA接口上时，路由器NIC的内存和处理限制可能会限制NHRP的可伸缩性。这是因为路由器通常处理来自多个来源的流量聚合，这反过来会在路由器的NBMA接口之外产生大量潜在的SVCC。
At the LIS level, the main issue is to maintain and deliver a sizable number of NBMA to Network layer address mappings within large LISs. To this goal, NHRP implementations can use the services of the Server Cache Synchronization Protocol (SCSP) [8] that allows multiple synchronized NHSs within an LIS, and hence resolve the associated scalability issue.
在LIS级别，主要问题是在大型LIS中维护和交付大量NBMA到网络层的地址映射。为了实现这一目标，NHRP实现可以使用服务器缓存同步协议（SCSP）[8]的服务，该协议允许在一个LIS中进行多个同步NHS，从而解决相关的可伸缩性问题。
At the NHRP Domain level, network layer routing is used in resolving the NBMA address of a destination outside the LIS. As such, the scalability of NHRP is closely tied to the scalability of the network layer routing protocol used by NHRP. Dynamic network layer routing protocols are proven to scale well. Thus, when used in conjunction with dynamic routing algorithms, at the NHRP domain level, NHRP should scale in the same order as the routing algorithm, subject to the assumption that all the routers along the path are NHRP aware. If an NHRP Request is processed by a router that does not implement NHRP, it will be silently discarded. Then, short-cuts cannot be implemented and connectivity will be provided on a hop-by-hop basis.
在NHRP域级别，网络层路由用于解析LIS之外目的地的NBMA地址。因此，NHRP的可伸缩性与NHRP使用的网络层路由协议的可伸缩性密切相关。动态网络层路由协议被证明具有良好的可扩展性。因此，当与动态路由算法结合使用时，在NHRP域级别，NHRP应按照与路由算法相同的顺序进行扩展，前提是路径上的所有路由器都是NHRP感知的。如果一个NHRP请求是由一个没有实现NHRP的路由器处理的，它将被悄悄地丢弃。然后，无法实施捷径，将在逐跳的基础上提供连接。
Thus, when NHRP is implemented in conjunction with dynamic network layer routing, a scaling requirement for NHRP is that virtually all the routers within a logical NBMA network should be NHRP aware.
因此，当NHRP与动态网络层路由一起实现时，NHRP的扩展要求是，逻辑NBMA网络中的几乎所有路由器都应该知道NHRP。
One can also use static routing in conjunction with NHRP. Then, not all the routers in the NBMA network need to be NHRP aware. That is, since the routers that need to process NHRP control messages are specified by static routing, routers that are not included in the manually defined static paths do not have to be NHRP aware. Of course, static routing does not scale, and if the destination is off the NBMA network, then the use of static routing could result in persistently suboptimal routes. Use of static routing also has fairly negative failure modes.
还可以将静态路由与NHRP结合使用。然后，并非NBMA网络中的所有路由器都需要知道NHRP。也就是说，由于需要处理NHRP控制消息的路由器由静态路由指定，因此不包括在手动定义的静态路径中的路由器不必具有NHRP感知。当然，静态路由不会扩展，如果目的地脱离NBMA网络，那么使用静态路由可能会导致持续的次优路由。使用静态路由也有相当消极的故障模式。
NHRP does not replace existing routing protocols. In general, routing protocols are used to determine the proper path from a source host or router, or intermediate router, to a particular destination. If the routing protocol indicates that the proper path is via an interface to an NBMA network, then NHRP may be used at the NBMA interface to resolve the destination IP address into the corresponding NBMA address. Of course, the use of NHRP is subject to considerations discussed in Section 4.
NHRP不会取代现有的路由协议。通常，路由协议用于确定从源主机或路由器或中间路由器到特定目的地的正确路径。如果路由协议指示正确路径是经由到NBMA网络的接口，则可以在NBMA接口处使用NHRP将目的地IP地址解析为相应的NBMA地址。当然，NHRP的使用取决于第4节中讨论的考虑因素。
Assuming that NHRP is applicable and the destination address has been resolved, packets are forwarded using the particular data forwarding and path determination mechanisms of the underlying NBMA network. Here, the sequence of events are such that route determination is performed by IP routing, independent of NHRP. Then, NHRP is used to create a short-cut track upon the path determined by the IP routing protocol. Therefore, NHRP "shortens" the routed path. NHRP (as defined in [1]) is not sufficient to suppress persistent forwarding loops when used for router-router communication if the underlying routing protocol looses information critical to loop suppression [9]. Work is in progress [10] to augment NHRP to enable its use for the router-router communication without persistent forwarding loops.
假设NHRP是适用的并且目的地地址已被解析，则使用底层NBMA网络的特定数据转发和路径确定机制来转发分组。这里，事件序列使得路由确定由独立于NHRP的IP路由执行。然后，NHRP用于在IP路由协议确定的路径上创建一条捷径。因此，NHRP“缩短”了路由路径。当用于路由器-路由器通信时，如果底层路由协议丢失了对环路抑制至关重要的信息[9]，则NHRP（如[1]中所定义）不足以抑制持久转发环路。正在进行的工作[10]旨在增强NHRP，使其能够在无持续转发循环的情况下用于路由器通信。
When the routed path keeps changing on some relatively short time scale, such as seconds, this situation will have an effect on the operation of NHRP. In certain router-router operations, changes in the routed path could create persistent routing loops. In host-router, or router-host communications, frequent changes in routed paths could result in inefficiencies such as frequent creation of short-cut paths which are short lived.
当路由路径在相对较短的时间尺度（如秒）上不断变化时，这种情况将对NHRP的运行产生影响。在某些路由器操作中，路由路径的更改可能会创建持久路由循环。在主机路由器或路由器-主机通信中，路由路径的频繁更改可能导致效率低下，例如频繁创建短寿命的捷径。
NHRP is an address resolution protocol, and SCSP is a database synchronization protocol. As such, they are possibly subject to server (for NHRP) or peer (for SCSP) spoofing and denial of service attacks. They both provide authentication mechanisms to allow their
NHRP是一种地址解析协议，SCSP是一种数据库同步协议。因此，它们可能受到服务器（针对NHRP）或对等方（针对SCSP）的欺骗和拒绝服务攻击。它们都提供身份验证机制，以允许
use in environments in which spoofing is a concern. Details can be found in sections 5.3.4 in [1] and B.3.1 in [8]. There are no additional security constraints or concerns raised in this document that are not already discussed in the referenced sections.
在涉及欺骗的环境中使用。详情见[1]第5.3.4节和[8]第B.3.1节。本文件中没有其他未在参考章节中讨论的安全约束或问题。
References
工具书类
[1] Luciani, J., Katz, D., Piscitello, D., Cole, B., and N. Doraswamy, "NMBA Next Hop Resolution Protocol (NHRP)", RFC 2332, April 1998.
[1] Luciani，J.，Katz，D.，Piscitello，D.，Cole，B.，和N.Doraswamy，“NMBA下一跳解析协议（NHRP）”，RFC 2332，1998年4月。
[2] Greene, M., and J. Luciani, "NHRP Management Information Base", Work in Progress.
[2] Greene，M.和J.Luciani，“NHRP管理信息库”，正在进行中。
[3] Laubach, M., and J. Halpern, "Classical IP and ARP over ATM", RFC 2225, April 1998.
[3] Laubach，M.和J.Halpern，“ATM上的经典IP和ARP”，RFC 22251998年4月。
[4] Lawrance, J., and D. Piscitello, "The Transmission of IP datagrams over the SMDS service", RFC 1209, March 1991.
[4] Lawrance，J.和D.Piscitello，“通过SMDS服务传输IP数据报”，RFC 1209，1991年3月。
[5] Multiprotocol Over ATM Version 1.0, ATM Forum Document af-mpoa-0087.000
[5] ATM上的多协议1.0版，ATM论坛文件af-mpoa-0087.000
[6] Rekhter, Y., and D. Farinacci, "Support for Sparse Mode PIM over ATM", Work in Progress.
[6] Y.Rekhter和D.Farinaci，“支持ATM上的稀疏模式PIM”，工作正在进行中。
[7] Rekhter, Y., and D. Kandlur, "Local/Remote" Forwarding Decision in Switched Data Link Subnetworks", RFC 1937, May 1996.
[7] Y.Rekhter和D.Kandlur，“交换数据链路子网中的本地/远程转发决策”，RFC 1937，1996年5月。
[8] Luciani, J., Armitage, G., Halpern, J., and N. Doraswamy, "Server Cache Synchronization Protocol (SCSP) - NBMA", RFC 2334, April 1998.
[8] Luciani，J.，Armitage，G.，Halpern，J.，和N.Doraswamy，“服务器缓存同步协议（SCSP）-NBMA”，RFC 2334，1998年4月。
[9] Cole, R., Shur, D., and C. Villamizar, "IP over ATM: A Framework Document", RFC 1932, April 1996.
[9] Cole，R.，Shur，D.，和C.Villamizar，“ATM上的IP：框架文件”，RFC 1932，1996年4月。
[10] Rekhter, Y., "NHRP for Destinations off the NBMA Subnetwork", Work in Progress.
[10] Rekhter，Y.，“NBMA子网外目的地的NHRP”，正在进行的工作。
Acknowledgements
致谢
The author acknowledges valuable contributions and comments from many participants of the ION Working Group, in particular from Joel Halpern of Newbridge Networks, David Horton of Centre for Information Technology Research, Andy Malis of Nexion, Yakov Rekhter and George Swallow of Cisco Systems and Curtis Villamizar of ANS.
作者感谢ION工作组许多参与者的宝贵贡献和评论，特别是新桥网络的Joel Halpern、信息技术研究中心的David Horton、Nexion的Andy Malis、思科系统的Yakov Rekhter和George Swallow以及ANS的Curtis Villamizar。
Author's Address
作者地址
Derya H. Cansever GTE Laboratories Inc. 40 Sylvan Rd. MS 51 Waltham MA 02254
德尔雅H.坎瑟夫GTE实验室有限公司，马萨诸塞州沃尔瑟姆市西尔文路40号，邮编：02254
Phone: +1 617 466 4086
EMail: dcansever@gte.com
Phone: +1 617 466 4086
EMail: dcansever@gte.com
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