RFC 2452 (rfc2452) - Page 2 of 10
IP Version 6 Management Information Base for the Transmission Control Protocol
Alternative Format: Original Text Document
RFC 2452 TCP MIB for IPv6 December 1998 Management stations execute management applications which monitor and control managed elements. Managed elements are devices such as hosts, routers, terminal servers, etc., which are monitored and controlled via access to their management information. Management information is viewed as a collection of managed objects, residing in a virtual information store, termed the Management Information Base (MIB). Collections of related objects are defined in MIB modules. These modules are written using a subset of OSI's Abstract Syntax Notation One (ASN.1) [1], termed the Structure of Management Information (SMI) [2]. 2. Overview This document is one in the series of documents that define various MIB objects, and statements of conformance, for IPv6. This document defines the required instrumentation for implementations of TCP over IPv6. 3. Transparency of IP versions to TCP The fact that a particular TCP connection uses IPv6 as opposed to IPv4, is largely invisible to a TCP implementation. A "TCPng" did not need to be defined, implementations simply need to support IPv6 addresses. As such, the managed objects already defined in [TCP MIB] are sufficient for managing TCP in the presence of IPv6. These objects are equally applicable whether the managed node supports IPv4 only, IPv6 only, or both IPv4 and IPv6. For example, tcpActiveOpens counts "The number of times TCP connections have made a direct transition to the SYN-SENT state from the CLOSED state", regardless of which version of IP is used between the connection endpoints. Stated differently, TCP implementations don't need separate counters for IPv4 and for IPv6. 4. Representing TCP Connections The exception to the statements in section 3 is the tcpConnTable. Since IPv6 addresses cannot be represented with the IpAddress syntax, not all TCP connections can be represented in the tcpConnTable defined in [TCP MIB]. Daniele Standards Track



