RFC 2962 (rfc2962) - Page 2 of 20
An SNMP Application Level Gateway for Payload Address Translation
Alternative Format: Original Text Document
RFC 2962 SNMP Payload Address Translation October 2000 This document includes a detailed description of the requirements and limitations for an implementation of an SNMP Application Level Gateway. It also discusses other approaches to exchange SNMP packets across conflicting addressing realms. Table of Contents 1. Introduction ..................................................2 2. Terminology and Concepts Used ................................5 3. Problem Scope and Requirements ................................5 3.1 IP Addresses in SNMP Messages ................................6 3.2 Requirements ..................................................7 4. Translating IP Addresses in SNMP Packets ......................7 4.1 Basic SNMP Application Level Gateway ..........................8 4.2 Advanced SNMP Application Level Gateway ......................8 4.3 Packet Size and UDP Checksum ..................................9 5. Limitations and Alternate Solutions .........................10 6. Security Considerations .....................................12 7. Summary and Recommendations .................................13 8. Current Implementations .....................................14 9. Acknowledgments .............................................14 10. References ...................................................14 11. Authors' Addresses ...........................................16 12. Description of the Encoding of SNMP Packets .................17 13. Full Copyright Statement .....................................20 1. Introduction The need for IP address translation arises when a network's internal IP addresses cannot be used outside the network. Using basic network address translation allows local hosts on such private networks (addressing realms) to transparently access the external global Internet and enables access to selective local hosts from the outside. In particular it is not unlikely to have several addressing realms that are using the same private IPv4 address space within the same organization. In many of these cases, there is a need to manage the local addressing realm from a manager site outside the domain. However, managing such a network presents unique problems and challenges. Most available management applications use SNMP (Simple Network Management Protocol) to retrieve information from the network elements. For example, a router may be queried by the management application about the addresses of its neighboring elements. This information is then sent by the router back to the management Raz, et al. Informational
