IPv6 MIB Revision Design Team Rajiv Raghunarayan, Editor INTERNET-DRAFT Cisco Systems Expires: August 2004 February 2004 Management Information Base for the Transmission Control Protocol (TCP) draft-ietf-ipv6-rfc2012-update-06.txt Status of this Document This document is an Internet-Draft and is in full conformance with all provisions of Section 10 of RFC2026. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that other groups may also distribute working documents as Internet-Drafts. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.txt The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This document is a product of the IPv6 MIB Revision Design Team. Comments should be addressed to the editor/authors or the mailing list at ipv6@ietf.org. Copyright Notice Copyright (C) The Internet Society (2004). All Rights Reserved. Abstract This memo defines a portion of the Management Information Base (MIB) for use with network management protocols in the Internet community. In particular, it describes managed objects used for implementations of the Transmission Control Protocol (TCP) in an IP version independent manner. This memo obsoletes RFCs 2012 and 2452. Raghunarayan, Editor [Page 1] INTERNET-DRAFT Expires: August 2004 February 2004 Table of Contents 1. The Internet-Standard Management Framework . . . . . . . . . . 6 2. Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . 6 3. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4. Acknowledgements. . . . . . . . . . . . . . . . . . . . . . . . 26 5. Normative References. . . . . . . . . . . . . . . . . . . . . . 26 6. Informative References. . . . . . . . . . . . . . . . . . . . . 26 7. Security Considerations . . . . . . . . . . . . . . . . . . . . 27 8. Intellectual Property . . . . . . . . . . . . . . . . . . . . . 28 9. Editor's Address. . . . . . . . . . . . . . . . . . . . . . . . 29 10. Authors. . . . . . . . . . . . . . . . . . . . . . . . . . . . 29 11. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 30 Revision History [Note to RFC Editor: Please remove prior to publication] Changes from draft-ietf-ipv6-rfc2012-update-05.txt: 4th February 2004 Added a new type 'rfc2988' to the tcpRtoAlgorithm list. Modified the description of tcpRtoMin and tcpRtoMax to point to RFC 2988 for more detailed information. Added RFC 2988 and RFC 3418 to the list of references. Updated the description of InetAddress objects - added a pointer to the corresponding InetAddressType objects. Updated tcpMIBCompliance2 to include unknown(0) as a value to be supported for tcpListenerLocalAddressType. Added an explicit reference to sysUpTime as a discontinuity indicator to the counter objects in the mib. Also updated the description of InetAddress objects used as index elements to indicate the 128 octet limit. Removed citations from within the mib. Changes from draft-ietf-ipv6-rfc2012-update-04.txt: 25th November 2003 As per consensus, removed the SIZE(0..36) restriction from InetAddress objects. This has been stated as a part of the compliance. Raghunarayan, Editor [Page 2] INTERNET-DRAFT Expires: August 2004 February 2004 Added an IPR section and a copyright statement to DESCRIPTION clause in MODULE-IDENTITY. Added an RFC Editor's note to change XXXX to RFC publication number. Updated contact addresses for Brian Haberman, Shawn Routhier and Dave Thaler. Shortened the author list on the front page to editor only. Changes from draft-ietf-ipv6-rfc2012-update-03.txt: 14th September 2003 Some editorial changes - correcting some spellings, and added a statement to indicate the deprecation of RFC 2012 and RFC 2542. Changes from draft-ietf-ipv6-rfc2012-update-02.txt: 16th June 2003 Added tcpHCInSegs and tcpHCOutSegs back to the mib, in order to have the 64-bit counters along with the 32-bit counters. Changes from draft-ietf-ipv6-rfc2012-update-01.txt: 23rd February 2003 Changes in this version mainly concentrate on reducing this mib to a bare minimum update of RFC 2012, enough to satisfy the needs of IPv6. The actual modifications are listed below. Scalars tcpHCInSegs and tcpHCOutSegs dropped. Objects dropped from the tcpConnectionTable include tcpConnectionInSegs, tcpConnectionOutSegs, tcpConnectionInOctets, tcpConnectionOutOctets, tcpConnectionHCInSegs, tcpConnectionHCOutSegs, tcpConnectionHCInOctets, tcpConnectionHCOutOctets, tcpConnectionAge and tcpConnectionId. Objects dropped from tcpListenerTable include tcpListenerTimeOuts, tcpListenerEstablished and tcpListenerAge. Updated compliance statements to reflect the aforementioned changes. Changes from draft-ietf-ipv6-rfc2012-update-00.txt: 4th November 2002 Raghunarayan, Editor [Page 3] INTERNET-DRAFT Expires: August 2004 February 2004 Replaced the tcpConnectionStartTime and tcpListenerStartTime objects with tcpConnectionAge and tcpListenerAge respectively. Added tcpConnectionRemAddressType as an auxiliary object into the tcpConnectionTable. Added new object, tcpConnectionId, to provide a link into the TCP-ESTATS-MIB. Included tcpConnectionAge and tcpConnectionProcess into the tcpConnectionGroup. Included tcpListenerAge and tcpListenerProcess into the tcpListenerGroup. tcpListenerGroup added to the mandatory list for compliance. Changes from draft-ietf-ipngwg-rfc2012-update-01.txt: 27 June 2002 Replaced all occurrences of the term packets to segments, to be consistent with the TCP specification. Added limits to tcpRtoMin, tcpRtoMax and tcpMaxConn. Added the scalar, tcpListenerTableLastChange. Updated the description of tcpConnectionLocalAddress - removed reference to 'listen' state. Updated the description tcpConnection*Octets to explicitly indicate whether the count includes the TCP header octets. Updated the description of tcpConnectionStartTime and tcpListenerStartTime - added clarifying text. Renamed tcpConnectionProcessID to tcpConnectionProcess. Updated the description of tcpListenerTable. Updated the description of tcpListenerLocalAddressType to include unknown (0) as a valid value. Updated the description of tcpListenerLocalAddress - the value ''h (zero-length octet-string) represents the case wherein an application is will to accept connections for any IP interface associated with the node. Removed tcpListenerRemAddressType. Raghunarayan, Editor [Page 4] INTERNET-DRAFT Expires: August 2004 February 2004 Removed tcpListenerHCConnectionsTimedOut and tcpListenerHCConnectionsAccepted. Added them to open issues, to be added iff deemed required after discussions. Renamed tcpListenerConnectionsAccepted to tcpListenerEstablished and tcpListenerConnectionsTimedOut to tcpListenerTimeOuts. Renamed tcpListenerProcessID to tcpListenerProcess. Updated compliance statement for the object tcpConnectionState - support for the value 'deleteTCB (12)' deemed optional. Added RFC 2790 and RFC 2287 to the References section. Updated Contact-Info and Editor's address. Added Authors section. Changes from draft-ietf-ipngwg-rfc2012-update-00.txt: 14 November 2001 Added HC versions of connection counters. Added Listener table, with counters for accepted and timed out connection attempts. Added tcp{Connection,Listener}ProcessID to index into SYSAPPL-MIB or HOST-RESOURCES-MIB. Removed tcpConnectionRemAddrType, it must be the same as tcpConnectionLocalAddrType. Changes from draft-ops-rfc2012-update-00.txt 12 Jul 2001 Turned into IPNG WG document Added tcpCountersGroup for per-connection counters Changes from first draft posted to v6mib mailing list: 23 Feb 2001 Made threshold for HC packet counters 1Mpps Added copyright statements and table of contents 21 Feb 2001 -- Juergen's changes Raghunarayan, Editor [Page 5] INTERNET-DRAFT Expires: August 2004 February 2004 Renamed tcpInetConn* to tcpConnection* Updated Conformance info Added missing tcpConnectionState and tcpConnState objects to SEQUENCEs 6 Feb 2001 Removed v6-only objects. Renamed inetTcp* to tcpInet* Added SIZE restriction to InetAddress index objects. (36 = 32-byte addresses plus 4-byte scope, but it's just a strawman) Used InetPortNumber TC from updated INET-ADDRESS-MIB Updated compliance statements. Added Keith to authors Added open issues section. Changes from RFC 2012 Deprecated tcpConnTable Added tcpConnectionTable 1. The Internet-Standard Management Framework For a detailed overview of the documents that describe the current Internet-Standard Management Framework, please refer to section 7 of RFC 3410 [RFC3410]. Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. MIB objects are generally accessed through the Simple Network Management Protocol (SNMP). Objects in the MIB are defined using the mechanisms defined in the Structure of Management Information (SMI). This memo specifies a MIB module that is compliant to the SMIv2, which is described in STD 58, RFC 2578 [RFC2578], STD 58, RFC 2579 [RFC2579] and STD 58, RFC 2580 [RFC2580]. 2. Overview The current TCP-MIB defined in this memo consists of two tables and a group of scalars: Raghunarayan, Editor [Page 6] INTERNET-DRAFT Expires: August 2004 February 2004 - The tcp group of scalars reports parameters and statistics of a TCP protocol engine. - The tcpConnectionTable provides access to status information for all TCP connections handled by a TCP protocol engine. In addition the table also reports identification of the operating system level processes which handle the TCP connections. - The tcpListenerTable provides access to information about all TCP listening endpoints known by a TCP protocol engine. And similar to the case of the connection table, the tcpListenerTable also reports the identification of the operating system level processes which handle this listening TCP endpoint. 2.1 Relationship to Other MIBs This section discusses the relationship of this TCP-MIB module to other MIB modules. 2.1.1 Relationship to RFC1213-MIB TCP related MIB objects were originally defined as part of the RFC1213-MIB defined in RFC 1213 [RFC1213]. The TCP related objects of the RFC1213-MIB were later copied into a separate MIB module and published in RFC 2012 [RFC2012] in SMIv2 format. The previous versions of the TCP-MIB both defined the tcpConnTable, which has been deprecated for basically two reasons: (1) The tcpConnTable only supports IPv4. The current approach in the IETF is to write IP version neutral MIBs rather than having different definitions for various version of IP. This reduces the amount of overhead when new objects are introduced since there is only one place to add them. Hence, the approach taken in RFC 2452 of having separate tables is not continued. (2) The tcpConnTable mixes listening endpoints with connections. It turns out that connections tend to have a different behaviour and management access pattern compared to listening endpoints. Splitting the original tcpConnTable into two tables thus allows for the addition of specific status and statistics objects for listening endpoints and connections. 2.1.2 Relationship to IPV6-TCP-MIB The IPV6-TCP-MIB defined in RFC 2452 has been moved to Historic since the approach of having separate IP version specific tables is not followed anymore. Implementation of RFC 2452 is thus not suggested anymore. Raghunarayan, Editor [Page 7] INTERNET-DRAFT Expires: August 2004 February 2004 2.1.3 Relationship to HOST-RESOURCES-MIB and SYSAPPL-MIB The tcpConnectionTable and the tcpListenerTable report the identification of the operating system level process which handles a connection or a listening endpoint. The value is reported as an Unsigned32 which is expected to be the same as the hrSWRunIndex of the HOST-RESOURCES-MIB [RFC2790] (if the value is smaller than 2147483647) or the sysApplElmtRunIndex of the SYSAPPL-MIB [RFC2287]. This allows managment applications to identify the TCP connections that belong to an operating system level process which has proven to be valuable in operational environments. 3. Definitions TCP-MIB DEFINITIONS ::= BEGIN IMPORTS MODULE-IDENTITY, OBJECT-TYPE, Integer32, Unsigned32, Gauge32, Counter32, Counter64, IpAddress, mib-2 FROM SNMPv2-SMI MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF InetAddress, InetAddressType, InetPortNumber FROM INET-ADDRESS-MIB; tcpMIB MODULE-IDENTITY LAST-UPDATED "200402040000Z" ORGANIZATION "IETF IPv6 MIB Revision Team http://www.ietf.org/html.charters/ipv6-charter.html" CONTACT-INFO "Rajiv Raghunarayan (editor) Cisco Systems Inc. 170 West Tasman Drive San Jose, CA 95134 Phone: +1 408 853 9612 Email: Send comments to " -- RFC Ed: please verify mailing list address at publication -- and delete this note DESCRIPTION "The MIB module for managing TCP implementations. Copyright (C) The Internet Society (2004). This version of this MIB module is a part of RFC xxxx; see the RFC itself for full legal notices." -- RFC Ed : replace xxxx with actual RFC number & remove note Raghunarayan, Editor [Page 8] INTERNET-DRAFT Expires: August 2004 February 2004 REVISION "200402040000Z" DESCRIPTION "IP version neutral revision, published as RFC XXXX." -- RFC Ed : replace xxxx with actual RFC number & remove note REVISION "9411010000Z" DESCRIPTION "Initial SMIv2 version, published as RFC 2012." REVISION "9103310000Z" DESCRIPTION "The initial revision of this MIB module was part of MIB-II." ::= { mib-2 49 } -- the TCP base variables group tcp OBJECT IDENTIFIER ::= { mib-2 6 } -- Scalars tcpRtoAlgorithm OBJECT-TYPE SYNTAX INTEGER { other(1), -- none of the following constant(2), -- a constant rto rsre(3), -- MIL-STD-1778, Appendix B vanj(4), -- Van Jacobson's algorithm rfc2988(5) -- RFC 2988 } MAX-ACCESS read-only STATUS current DESCRIPTION "The algorithm used to determine the timeout value used for retransmitting unacknowledged octets." ::= { tcp 1 } tcpRtoMin OBJECT-TYPE SYNTAX Integer32 (0..2147483647) UNITS "milliseconds" MAX-ACCESS read-only STATUS current DESCRIPTION "The minimum value permitted by a TCP implementation for the retransmission timeout, measured in milliseconds. More refined semantics for objects of this type depend upon the algorithm used to determine the retransmission timeout; in particular, the IETF standard algorithm rfc2988(5) provides a minimum value." ::= { tcp 2 } Raghunarayan, Editor [Page 9] INTERNET-DRAFT Expires: August 2004 February 2004 tcpRtoMax OBJECT-TYPE SYNTAX Integer32 (0..2147483647) UNITS "milliseconds" MAX-ACCESS read-only STATUS current DESCRIPTION "The maximum value permitted by a TCP implementation for the retransmission timeout, measured in milliseconds. More refined semantics for objects of this type depend upon the algorithm used to determine the retransmission timeout; in particular, the IETF standard algorithm rfc2988(5) provides an upper bound (as part of an adaptive backoff algorithm)." ::= { tcp 3 } tcpMaxConn OBJECT-TYPE SYNTAX Integer32 (-1 | 0..2147483647) MAX-ACCESS read-only STATUS current DESCRIPTION "The limit on the total number of TCP connections the entity can support. In entities where the maximum number of connections is dynamic, this object should contain the value -1." ::= { tcp 4 } tcpActiveOpens OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of times TCP connections have made a direct transition to the SYN-SENT state from the CLOSED state. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 5 } Raghunarayan, Editor [Page 10] INTERNET-DRAFT Expires: August 2004 February 2004 tcpPassiveOpens OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of times TCP connections have made a direct transition to the SYN-RCVD state from the LISTEN state. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 6 } tcpAttemptFails OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of times TCP connections have made a direct transition to the CLOSED state from either the SYN-SENT state or the SYN-RCVD state, plus the number of times TCP connections have made a direct transition to the LISTEN state from the SYN-RCVD state. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 7 } tcpEstabResets OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of times TCP connections have made a direct transition to the CLOSED state from either the ESTABLISHED state or the CLOSE-WAIT state. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 8 } Raghunarayan, Editor [Page 11] INTERNET-DRAFT Expires: August 2004 February 2004 tcpCurrEstab OBJECT-TYPE SYNTAX Gauge32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of TCP connections for which the current state is either ESTABLISHED or CLOSE-WAIT." ::= { tcp 9 } tcpInSegs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of segments received, including those received in error. This count includes segments received on currently established connections. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 10 } tcpOutSegs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of segments sent, including those on current connections but excluding those containing only retransmitted octets. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 11 } Raghunarayan, Editor [Page 12] INTERNET-DRAFT Expires: August 2004 February 2004 tcpRetransSegs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of segments retransmitted - that is, the number of TCP segments transmitted containing one or more previously transmitted octets. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 12 } tcpInErrs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of segments received in error (e.g., bad TCP checksums). Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 14 } tcpOutRsts OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of TCP segments sent containing the RST flag. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 15 } -- { tcp 16 } was used to represent the ipv6TcpConnTable in RFC 2452, -- which has since been obsoleted. It MUST not be used. Raghunarayan, Editor [Page 13] INTERNET-DRAFT Expires: August 2004 February 2004 tcpHCInSegs OBJECT-TYPE SYNTAX Counter64 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of segments received, including those received in error. This count includes segments received on currently established connections. This object is the 64-bit equivalent of tcpInSegs. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 17 } tcpHCOutSegs OBJECT-TYPE SYNTAX Counter64 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of segments sent, including those on current connections but excluding those containing only retransmitted octets. This object is the 64-bit equivalent of tcpOutSegs. Discontinuities in the value of this counter can occur at re-initialization of the management system, and at other times as indicated by discontinuities the value of sysUpTime." ::= { tcp 18 } -- The TCP Connection table tcpConnectionTable OBJECT-TYPE SYNTAX SEQUENCE OF TcpConnectionEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A table containing information about existing TCP connections. Note that unlike earlier TCP MIBs, there is a separate table for connections in the LISTEN state." ::= { tcp 19 } Raghunarayan, Editor [Page 14] INTERNET-DRAFT Expires: August 2004 February 2004 tcpConnectionEntry OBJECT-TYPE SYNTAX TcpConnectionEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A conceptual row of the tcpConnectionTable containing information about a particular current TCP connection. Each row of this table is transient, in that it ceases to exist when (or soon after) the connection makes the transition to the CLOSED state." INDEX { tcpConnectionLocalAddressType, tcpConnectionLocalAddress, tcpConnectionLocalPort, tcpConnectionRemAddressType, tcpConnectionRemAddress, tcpConnectionRemPort } ::= { tcpConnectionTable 1 } TcpConnectionEntry ::= SEQUENCE { tcpConnectionLocalAddressType InetAddressType, tcpConnectionLocalAddress InetAddress, tcpConnectionLocalPort InetPortNumber, tcpConnectionRemAddressType InetAddressType, tcpConnectionRemAddress InetAddress, tcpConnectionRemPort InetPortNumber, tcpConnectionState INTEGER, tcpConnectionProcess Unsigned32 } tcpConnectionLocalAddressType OBJECT-TYPE SYNTAX InetAddressType MAX-ACCESS not-accessible STATUS current DESCRIPTION "The address type of tcpConnectionLocalAddress." ::= { tcpConnectionEntry 1 } tcpConnectionLocalAddress OBJECT-TYPE SYNTAX InetAddress MAX-ACCESS not-accessible STATUS current DESCRIPTION "The local IP address for this TCP connection. The type of this address is determined by the value of tcpConnectionLocalAddressType. As this object is used in the index for the tcpConnectionTable, implementors of this table should be careful not to create entries that would result in OIDs with more than 128 subidentifiers; else the information cannot be accessed using SNMPv1, SNMPv2c or SNMPv3." ::= { tcpConnectionEntry 2 } Raghunarayan, Editor [Page 15] INTERNET-DRAFT Expires: August 2004 February 2004 tcpConnectionLocalPort OBJECT-TYPE SYNTAX InetPortNumber MAX-ACCESS not-accessible STATUS current DESCRIPTION "The local port number for this TCP connection." ::= { tcpConnectionEntry 3 } tcpConnectionRemAddressType OBJECT-TYPE SYNTAX InetAddressType MAX-ACCESS not-accessible STATUS current DESCRIPTION "The address type of tcpConnectionRemAddress." ::= { tcpConnectionEntry 4 } tcpConnectionRemAddress OBJECT-TYPE SYNTAX InetAddress MAX-ACCESS not-accessible STATUS current DESCRIPTION "The remote IP address for this TCP connection. The type of this address is determined by the value of tcpConnectionRemAddressType. As this object is used in the index for the tcpConnectionTable, implementors of this table should be careful not to create entries that would result in OIDs with more than 128 subidentifiers; else the information cannot be accessed using SNMPv1, SNMPv2c or SNMPv3." ::= { tcpConnectionEntry 5 } tcpConnectionRemPort OBJECT-TYPE SYNTAX InetPortNumber MAX-ACCESS not-accessible STATUS current DESCRIPTION "The remote port number for this TCP connection." ::= { tcpConnectionEntry 6 } Raghunarayan, Editor [Page 16] INTERNET-DRAFT Expires: August 2004 February 2004 tcpConnectionState OBJECT-TYPE SYNTAX INTEGER { closed(1), listen(2), synSent(3), synReceived(4), established(5), finWait1(6), finWait2(7), closeWait(8), lastAck(9), closing(10), timeWait(11), deleteTCB(12) } MAX-ACCESS read-write STATUS current DESCRIPTION "The state of this TCP connection. The value listen(2) is included only for parallelism to the old tcpConnTable, and should not be used. A connection in LISTEN state should be present in the tcpListenerTable. The only value which may be set by a management station is deleteTCB(12). Accordingly, it is appropriate for an agent to return a `badValue' response if a management station attempts to set this object to any other value. If a management station sets this object to the value deleteTCB(12), then this has the effect of deleting the TCB (as defined in RFC 793) of the corresponding connection on the managed node, resulting in immediate termination of the connection. As an implementation-specific option, a RST segment may be sent from the managed node to the other TCP endpoint (note however that RST segments are not sent reliably)." ::= { tcpConnectionEntry 7 } tcpConnectionProcess OBJECT-TYPE SYNTAX Unsigned32 MAX-ACCESS read-only STATUS current DESCRIPTION "The system's process ID for the process associated with this connection, or zero if there is no such process. This value is expected to be the same as HOST-RESOURCES-MIB:: hrSWRunIndex or SYSAPPL-MIB::sysApplElmtRunIndex for some row in the appropriate tables." ::= { tcpConnectionEntry 8 } Raghunarayan, Editor [Page 17] INTERNET-DRAFT Expires: August 2004 February 2004 -- The TCP Listener table tcpListenerTable OBJECT-TYPE SYNTAX SEQUENCE OF TcpListenerEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A table containing information about TCP listeners. A listening application can be represented in three possible ways: 1. An application that is willing to accept both IPv4 and IPv6 datagrams is represented by tcpListenerLocalAddressType of unknown (0) and tcpListenerLocalAddress of ''h (a zero-length octet-string). 2. An application which is willing to accept only IPv4 or IPv6 datagrams is represented by a tcpListenerLocalAddressType of the appropriate address type and tcpListenerLocalAddress of ''h (a zero-length octet-string). 3. An application which is a listening for data destined only to a specific IP address, but from any remote system, is represented by a tcpListenerLocalAddressType of an appropriate address type, with tcpListenerLocalAddress the specific local address. NOTE: The address type in this table represents the address type used for the communication, irrespective of the higher-layer abstraction. For example, an application using IPv6 'sockets' to communicate via IPv4 between ::ffff:10.0.0.1 and ::ffff:10.0.0.2 would use InetAddressType ipv4(1))." ::= { tcp 20 } tcpListenerEntry OBJECT-TYPE SYNTAX TcpListenerEntry MAX-ACCESS not-accessible STATUS current DESCRIPTION "A conceptual row of the tcpListenerTable containing information about a particular TCP listener." INDEX { tcpListenerLocalAddressType, tcpListenerLocalAddress, tcpListenerLocalPort } ::= { tcpListenerTable 1 } Raghunarayan, Editor [Page 18] INTERNET-DRAFT Expires: August 2004 February 2004 TcpListenerEntry ::= SEQUENCE { tcpListenerLocalAddressType InetAddressType, tcpListenerLocalAddress InetAddress, tcpListenerLocalPort InetPortNumber, tcpListenerProcess Unsigned32 } tcpListenerLocalAddressType OBJECT-TYPE SYNTAX InetAddressType MAX-ACCESS not-accessible STATUS current DESCRIPTION "The address type of tcpListenerLocalAddress. The value should be unknown (0) if connection initiation to all local IP addresses are accepted." ::= { tcpListenerEntry 1 } tcpListenerLocalAddress OBJECT-TYPE SYNTAX InetAddress MAX-ACCESS not-accessible STATUS current DESCRIPTION "The local IP address for this TCP connection. In the case of a listener which is willing to accept connections for any IP interface associated with the node, a value of ''h (zero-length octet-string) is used. The type of this address is determined by the value of tcpListenerLocalAddressType. As this object is used in the index for the tcpListenerTable, implementors of this table should be careful not to create entries that would result in OIDs with more than 128 subidentifiers; else the information cannot be accessed using SNMPv1, SNMPv2c or SNMPv3." ::= { tcpListenerEntry 2 } tcpListenerLocalPort OBJECT-TYPE SYNTAX InetPortNumber MAX-ACCESS not-accessible STATUS current DESCRIPTION "The local port number for this TCP connection." ::= { tcpListenerEntry 3 } Raghunarayan, Editor [Page 19] INTERNET-DRAFT Expires: August 2004 February 2004 tcpListenerProcess OBJECT-TYPE SYNTAX Unsigned32 MAX-ACCESS read-only STATUS current DESCRIPTION "The system's process ID for the process associated with this listener, or zero if there is no such process. This value is expected to be the same as HOST-RESOURCES-MIB:: hrSWRunIndex or SYSAPPL-MIB::sysApplElmtRunIndex for some row in the appropriate tables." ::= { tcpListenerEntry 4 } -- The deprecated TCP Connection table tcpConnTable OBJECT-TYPE SYNTAX SEQUENCE OF TcpConnEntry MAX-ACCESS not-accessible STATUS deprecated DESCRIPTION "A table containing information about existing IPv4-specific TCP connections or listeners. This table has been deprecated in favor of the version neutral tcpConnectionTable." ::= { tcp 13 } tcpConnEntry OBJECT-TYPE SYNTAX TcpConnEntry MAX-ACCESS not-accessible STATUS deprecated DESCRIPTION "A conceptual row of the tcpConnTable containing information about a particular current IPv4 TCP connection. Each row of this table is transient, in that it ceases to exist when (or soon after) the connection makes the transition to the CLOSED state." INDEX { tcpConnLocalAddress, tcpConnLocalPort, tcpConnRemAddress, tcpConnRemPort } ::= { tcpConnTable 1 } TcpConnEntry ::= SEQUENCE { tcpConnState INTEGER, tcpConnLocalAddress IpAddress, tcpConnLocalPort Integer32, tcpConnRemAddress IpAddress, tcpConnRemPort Integer32 } Raghunarayan, Editor [Page 20] INTERNET-DRAFT Expires: August 2004 February 2004 tcpConnState OBJECT-TYPE SYNTAX INTEGER { closed(1), listen(2), synSent(3), synReceived(4), established(5), finWait1(6), finWait2(7), closeWait(8), lastAck(9), closing(10), timeWait(11), deleteTCB(12) } MAX-ACCESS read-write STATUS deprecated DESCRIPTION "The state of this TCP connection. The only value which may be set by a management station is deleteTCB(12). Accordingly, it is appropriate for an agent to return a `badValue' response if a management station attempts to set this object to any other value. If a management station sets this object to the value deleteTCB(12), then this has the effect of deleting the TCB (as defined in RFC 793) of the corresponding connection on the managed node, resulting in immediate termination of the connection. As an implementation-specific option, a RST segment may be sent from the managed node to the other TCP endpoint (note however that RST segments are not sent reliably)." ::= { tcpConnEntry 1 } tcpConnLocalAddress OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS deprecated DESCRIPTION "The local IP address for this TCP connection. In the case of a connection in the listen state which is willing to accept connections for any IP interface associated with the node, the value 0.0.0.0 is used." ::= { tcpConnEntry 2 } Raghunarayan, Editor [Page 21] INTERNET-DRAFT Expires: August 2004 February 2004 tcpConnLocalPort OBJECT-TYPE SYNTAX Integer32 (0..65535) MAX-ACCESS read-only STATUS deprecated DESCRIPTION "The local port number for this TCP connection." ::= { tcpConnEntry 3 } tcpConnRemAddress OBJECT-TYPE SYNTAX IpAddress MAX-ACCESS read-only STATUS deprecated DESCRIPTION "The remote IP address for this TCP connection." ::= { tcpConnEntry 4 } tcpConnRemPort OBJECT-TYPE SYNTAX Integer32 (0..65535) MAX-ACCESS read-only STATUS deprecated DESCRIPTION "The remote port number for this TCP connection." ::= { tcpConnEntry 5 } -- conformance information tcpMIBConformance OBJECT IDENTIFIER ::= { tcpMIB 2 } tcpMIBCompliances OBJECT IDENTIFIER ::= { tcpMIBConformance 1 } tcpMIBGroups OBJECT IDENTIFIER ::= { tcpMIBConformance 2 } -- compliance statements tcpMIBCompliance2 MODULE-COMPLIANCE STATUS current DESCRIPTION "The compliance statement for systems which implement TCP. There are a number of INDEX objects that cannot be represented in the form of OBJECT clauses in SMIv2, but for which we have the following compliance requirements, expressed in OBJECT clause form in this description clause: Raghunarayan, Editor [Page 22] INTERNET-DRAFT Expires: August 2004 February 2004 -- OBJECT tcpConnectionLocalAddressType -- SYNTAX InetAddressType { ipv4(1), ipv6(2) } -- DESCRIPTION -- This MIB requires support for only global IPv4 -- and IPv6 address types. -- -- OBJECT tcpConnectionRemAddressType -- SYNTAX InetAddressType { ipv4(1), ipv6(2) } -- DESCRIPTION -- This MIB requires support for only global IPv4 -- and IPv6 address types. -- -- OBJECT tcpListenerLocalAddressType -- SYNTAX InetAddressType { unknown(0), ipv4(1), -- ipv6(2) } -- DESCRIPTION -- This MIB requires support for only global IPv4 -- and IPv6 address types. The type unknown also -- needs to be supported to identify a special -- case in the listener table - a listen using -- both IPv4 and IPv6 addresses on the device. -- " MODULE -- this module MANDATORY-GROUPS { tcpBaseGroup, tcpConnectionGroup, tcpListenerGroup } GROUP tcpHCGroup DESCRIPTION "This group is mandatory for those systems which are capable of receiving or transmitting more than 1 million TCP segments per second. 1 million segments per second will cause a Counter32 to wrap in just over an hour." OBJECT tcpConnectionState SYNTAX INTEGER { closed(1), listen(2), synSent(3), synReceived(4), established(5), finWait1(6), finWait2(7), closeWait(8), lastAck(9), closing(10), timeWait(11) } MIN-ACCESS read-only DESCRIPTION "Write access is not required, nor is support for the value deleteTCB (12)." ::= { tcpMIBCompliances 2 } Raghunarayan, Editor [Page 23] INTERNET-DRAFT Expires: August 2004 February 2004 tcpMIBCompliance MODULE-COMPLIANCE STATUS deprecated DESCRIPTION "The compliance statement for IPv4-only systems which implement TCP. In order to be IP version independent, this compliance statement is deprecated in favor of tcpMIBCompliance2. However, agents are still encouraged to implement these objects in order to interoperate with the deployed base of managers." MODULE -- this module MANDATORY-GROUPS { tcpGroup } OBJECT tcpConnState MIN-ACCESS read-only DESCRIPTION "Write access is not required." ::= { tcpMIBCompliances 1 } -- units of conformance tcpGroup OBJECT-GROUP OBJECTS { tcpRtoAlgorithm, tcpRtoMin, tcpRtoMax, tcpMaxConn, tcpActiveOpens, tcpPassiveOpens, tcpAttemptFails, tcpEstabResets, tcpCurrEstab, tcpInSegs, tcpOutSegs, tcpRetransSegs, tcpConnState, tcpConnLocalAddress, tcpConnLocalPort, tcpConnRemAddress, tcpConnRemPort, tcpInErrs, tcpOutRsts } STATUS deprecated DESCRIPTION "The tcp group of objects providing for management of TCP entities." ::= { tcpMIBGroups 1 } tcpBaseGroup OBJECT-GROUP OBJECTS { tcpRtoAlgorithm, tcpRtoMin, tcpRtoMax, tcpMaxConn, tcpActiveOpens, tcpPassiveOpens, tcpAttemptFails, tcpEstabResets, tcpCurrEstab, tcpInSegs, tcpOutSegs, tcpRetransSegs, tcpInErrs, tcpOutRsts } STATUS current DESCRIPTION "The group of counters common to TCP entities." ::= { tcpMIBGroups 2 } Raghunarayan, Editor [Page 24] INTERNET-DRAFT Expires: August 2004 February 2004 tcpConnectionGroup OBJECT-GROUP OBJECTS { tcpConnectionState, tcpConnectionProcess } STATUS current DESCRIPTION "The group provides general information about TCP connections." ::= { tcpMIBGroups 3 } tcpListenerGroup OBJECT-GROUP OBJECTS { tcpListenerProcess } STATUS current DESCRIPTION "This group has objects providing general information about TCP listeners." ::= { tcpMIBGroups 4 } tcpHCGroup OBJECT-GROUP OBJECTS { tcpHCInSegs, tcpHCOutSegs } STATUS current DESCRIPTION "The group of objects providing for counters of high speed TCP implementations." ::= { tcpMIBGroups 5 } END Raghunarayan, Editor [Page 25] INTERNET-DRAFT Expires: August 2004 February 2004 4. Acknowledgements This document contains a modified subset of RFC 1213 and updates RFC 2012 and RFC 2452. Acknowledgements are therefore due to the authors and editors of these documents for their excellent work. Several useful comments regarding usability and design were also received from Kristine Adamson. The authors would like to like all these people for their contribution to this effort. 5. Normative References [RFC793] Postel, J., "Transmission Control Protocol - DARPA Internet Program Protocol Specification", STD 7, RFC 793, DARPA, September 1981. [RFC2287] Krupczak, C., Saperia, J., "Definitions of System-Level Managed Objects for Applications", RFC 2287, February 1998. [RFC2790] Waldbusser, S., Grillo, P., "Host Resources MIB", RFC 2790, March 2000. [RFC2578] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Structure of Management Information Version 2 (SMIv2)", STD 58, RFC 2578, April 1999. [RFC2579] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M. and S. Waldbusser, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999. [RFC3291] Daniele, M., Haberman, B., Routhier, S., and Schoenwaelder, J., "Textual Conventions for Internet Network Addresses", RFC 3291, May 2002. [RFC3418] Presuhn, R., "Management Information Base (MIB) for the Simple Network Management Protocol (SNMP)", RFC 3418, December 2002. 6. Informative References [RFC1213] Rose, M. and K. McCloghrie, "Management Information Base for Network Management of TCP/IP-based internets", RFC 1213, March 1991. Raghunarayan, Editor [Page 26] INTERNET-DRAFT Expires: August 2004 February 2004 [RFC2012] K. McCloghrie, "SNMPv2 Management Information Base for the Transmission Control Protocol using SMIv2", RFC 2012, November 1996. [RFC2452] Daniele, M., "IP Version 6 Management Information Base for the Transmission Control Protocol", RFC 2452, December 1998. [RFC2988] Paxson, V., Allman, M., "Computing TCP's Retransmission Timer", RFC2988, November 2000. [RFC3410] Case, J., Mundy, R., Partain, D. and B. Stewart, "Introduction and Applicability Statements for Internet- Standard Management Framework", RFC 3410, December 2002. [VANJ] Jacobson, V., "Congestion Avoidance and Control", SIGCOMM 1988, Stanford, California. 7. Security Considerations There are management objects defined in this MIB that have a MAX-ACCESS clause of read-write. Such objects may be considered sensitive or vulnerable in some network environments. The support for SET operations in a non-secure environment without proper protection can have a negative effect on network operations. These are the tables and objects and their sensitivity/vulnerability: o The tcpConnectionState and tcpConnState objects have a MAX-ACCESS clause of read-write, which allows termination of an arbitrary connection. Unauthorized access could cause a denial of service. Some of the readable objects in this MIB module (i.e., objects with a MAX-ACCESS other than not-accessible) may be considered sensitive or vulnerable in some network environments. It is thus important to control even GET and/or NOTIFY access to these objects and possibly to even encrypt the values of these objects when sending them over the network via SNMP. These are the tables and objects and their sensitivity/vulnerability: o The tcpConnectionTable and the tcpConnTable contain objects providing information on the active connections on the device, the status of these connections and the associated processes. This information may be used by an attacker to launch attacks against known/unknown weakness in certain protocols/applications. In addition, access to the connection table could also have privacy implications since it provide detailed information on active connections. Raghunarayan, Editor [Page 27] INTERNET-DRAFT Expires: August 2004 February 2004 o The tcpListenerTable and the tcpConnTable contain objects providing information on listeners on an entity. For e.g. the tcpListenerLocalPort and tcpConnLocalPort objects can be used to identify what ports are open on the machine and can thus what attacks are likely to succeed, without the attacker having to run a port scanner. SNMP versions prior to SNMPv3 did not include adequate security. Even if the network itself is secure (for example by using IPSec), even then, there is no control as to who on the secure network is allowed to access and GET/SET (read/change/create/delete) the objects in this MIB module. It is RECOMMENDED that implementers consider the security features as provided by the SNMPv3 framework (see [RFC3410], section 8), including full support for the SNMPv3 cryptographic mechanisms (for authentication and privacy). Further, deployment of SNMP versions prior to SNMPv3 is NOT RECOMMENDED. Instead, it is RECOMMENDED to deploy SNMPv3 and to enable cryptographic security. It is then a customer/operator responsibility to ensure that the SNMP entity giving access to an instance of this MIB module is properly configured to give access to the objects only to those principals (users) that have legitimate rights to indeed GET or SET (change/create/delete) them. 8. Intellectual Property The IETF takes no position regarding the validity or scope of any intellectual property or other rights that might be claimed to pertain to the implementation or use of the technology described in this document or the extent to which any license under such rights might or might not be available; neither does it represent that it has made any effort to identify any such rights. Information on the IETF's procedures with respect to rights in standards-track and standards-related documentation can be found in BCP-11. Copies of claims of rights made available for publication and any assurances of licenses to be made available, or the result of an attempt made to obtain a general license or permission for the use of such proprietary rights by implementors or users of this specification can be obtained from the IETF Secretariat. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. Raghunarayan, Editor [Page 28] INTERNET-DRAFT Expires: August 2004 February 2004 9. Editor's Address Rajiv Raghunarayan Cisco Systems Inc. 170 West Tasman Drive San Jose, CA 95134 USA Email: raraghun@cisco.com 10. Authors This document is an output of the IPv6 MIB revision team, and contributors to earlier versions of this document include: Bill Fenner, AT&T Labs -- Research Email: fenner@research.att.com Brian Haberman Email: brian@innovationslab.net Shawn A. Routhier, Wind River Email: shawn.routhier@windriver.com Juergen Schoenwalder, TU Braunschweig Email: schoenw@ibr.cs.tu-bs.de Dave Thaler, Microsoft Email: dthaler@windows.microsoft.com This documents updates parts of the MIBs from several documents. RFC 2012 has been the base document for these updations. RFC 2452 was the first document to define the managed objects for implementations of TCP over IPv6. RFC 2012: Keith McCloghrie, Cisco Systems (Editor) kzm@cisco.com RFC 2452: Mike Daniele, Compaq Computer Corporation daniele@zk3.dec.com Raghunarayan, Editor [Page 29] INTERNET-DRAFT Expires: August 2004 February 2004 11. Full Copyright Statement Copyright (C) The Internet Society (2004). 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. Raghunarayan, Editor [Page 30]