IPv6 MIB Revision Design Team Bill Fenner INTERNET-DRAFT AT&T Research Expires: December 2002 Keith McCloghrie Rajiv Raghunarayan (Editor) Cisco Systems Juergen Schoenwalder TU Braunschweig June 2002 Management Information Base for the Transmission Control Protocol (TCP) draft-ietf-ipv6-rfc2012-update-00.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 ipng@sunroof.eng.sun.com. Copyright Notice Copyright (C) The Internet Society (2001). 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) [5] in an IP version independent manner. Raghunarayan, Editor [Page 1] INTERNET-DRAFT Expires: December 2002 June 2002 Table of Contents 1. The SNMP Management Framework . . . . . . . . . . . . . . . . . 2 2. Revision History. . . . . . . . . . . . . . . . . . . . . . . . 3 3. Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 4. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . 7 5. Open Issues . . . . . . . . . . . . . . . . . . . . . . . . . . 24 6. Acknowledgements. . . . . . . . . . . . . . . . . . . . . . . . 24 7. References. . . . . . . . . . . . . . . . . . . . . . . . . . . 25 8. Security Considerations . . . . . . . . . . . . . . . . . . . . 26 9. Editor's Address. . . . . . . . . . . . . . . . . . . . . . . . 27 10. Authors. . . . . . . . . . . . . . . . . . . . . . . . . . . . 27 11. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 28 1. The SNMP Management Framework The SNMP Management Framework presently consists of five major components: o An overall architecture, described in RFC 2571 [7]. o Mechanisms for describing and naming objects and events for the purpose of management. The first version of this Structure of Management Information (SMI) is called SMIv1 and described in STD 16, RFC 1155 [8], STD 16, RFC 1212 [9] and RFC 1215 [10]. The second version, called SMIv2, is described in STD 58, RFC 2578 [11], STD 58, RFC 2579 [12] and STD 58, RFC 2580 [13]. o Message protocols for transferring management information. The first version of the SNMP message protocol is called SNMPv1 and described in STD 15, RFC 1157 [14]. A second version of the SNMP message protocol, which is not an Internet standards track protocol, is called SNMPv2c and described in RFC 1901 [15] and RFC 1906 [16]. The third version of the message protocol is called SNMPv3 and described in RFC 1906 [16], RFC 2572 [17] and RFC 2574 [18]. o Protocol operations for accessing management information. The first set of protocol operations and associated PDU formats is described in STD 15, RFC 1157 [14]. A second set of protocol operations and associated PDU formats is described in RFC 1905 [19]. o A set of fundamental applications described in RFC 2573 [20] and the view-based access control mechanism described in RFC 2575 [21]. A more detailed introduction to the current SNMP Management Framework can be found in RFC 2570 [22]. Raghunarayan, Editor [Page 2] INTERNET-DRAFT Expires: December 2002 June 2002 Managed objects are accessed via a virtual information store, termed the Management Information Base or MIB. Objects in the MIB are defined using the mechanisms defined in the SMI. This memo specifies a MIB module that is compliant to the SMIv2. A MIB conforming to the SMIv1 can be produced through the appropriate translations. The resulting translated MIB must be semantically equivalent, except where objects or events are omitted because no translation is possible (use of Counter64). Some machine readable information in SMIv2 will be converted into textual descriptions in SMIv1 during the translation process. However, this loss of machine readable information is not considered to change the semantics of the MIB. 2. Revision History 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 3] INTERNET-DRAFT Expires: December 2002 June 2002 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 Raghunarayan, Editor [Page 4] INTERNET-DRAFT Expires: December 2002 June 2002 21 Feb 2001 -- Juergen's changes 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 3. Overview The current TCP-MIB defined in this memo consists of two tables an a group of scalars: - The tcp group of scalars reports parameters and statistics of a TCP protocol engine. Three scalars have been added to this group since the publication of RFC 2012. The first two, tcpHCInSegs and tcpHCOutSegs, provide high-capacity counters for fast networks. The third one, tcpListenerTableLastChange, provides management stations with an easier mechanism to validate their listener caches. - The tcpConnectionTable provides access to status information for all TCP connections handled by a TCP protocol engine. The table also contains basic per connection statistics such as the number of segments/octets received and sent and it reports identification of the operating system level processes which handles TCP connections and the start time of a connection. Raghunarayan, Editor [Page 5] INTERNET-DRAFT Expires: December 2002 June 2002 - The tcpListenerTable provides access to information about all TCP listening endpoints known by a TCP protocol engine. The table also contains basic per listening endpoint statistics such as the number of connections established (tcpListenerEstablished), number of connections that timed out (tcpListenerTimeOuts). Together, tcpListenerEstablished and tcpListenerTimeOuts, also provide an indication of the total number of connections accepted. Finally, the tcpListenerTable also reports the identification of the operating system level processes which handles this listening TCP endpoint and the start time when the listening endpoint was created. 3.1 Relationship to Other MIBs This section discusses the relationship of this TCP-MIB module to other MIB modules. 3.1.1 Relationship to RFC1213-MIB TCP related MIB objects were originally defined as part of the RFC1213-MIB defined in RFC 1213 [2]. The TCP related objects of the RFC1213-MIB were later copied into a separate MIB module and published in RFC 2012 [3] 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 to add specific status and statistic objects for listening endpoints and connections. 3.1.2 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 6] INTERNET-DRAFT Expires: December 2002 June 2002 3.1.3 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 (RFC 2790 [24]) (if the value is smaller than 2147483647) or the sysApplElmtRunIndex of the SYSAPPL-MIB (RFC 2287 [23]). 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. 4. Definitions TCP-MIB DEFINITIONS ::= BEGIN IMPORTS MODULE-IDENTITY, OBJECT-TYPE, Integer32, Unsigned32, Gauge32, Counter32, Counter64, IpAddress, mib-2 FROM SNMPv2-SMI TimeStamp FROM SNMPv2-TC MODULE-COMPLIANCE, OBJECT-GROUP FROM SNMPv2-CONF InetAddress, InetAddressType, InetPortNumber FROM INET-ADDRESS-MIB; tcpMIB MODULE-IDENTITY LAST-UPDATED "200206220000Z" ORGANIZATION "IETF IPv6 MIB Revision Team" CONTACT-INFO "Rajiv Raghunarayan (editor) Cisco Systems Inc. 170 West Tasman Drive San Jose, CA 95134 Phone: +1 408 853 9612 Email: " DESCRIPTION "The MIB module for managing TCP implementations." REVISION "200206220000Z" DESCRIPTION "IP version neutral revision, published as RFC XXXX." 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 } Raghunarayan, Editor [Page 7] INTERNET-DRAFT Expires: December 2002 June 2002 -- 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 [1] } 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, when the timeout algorithm is rsre(3), an object of this type has the semantics of the LBOUND quantity described in RFC 793." ::= { tcp 2 } 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, when the timeout algorithm is rsre(3), an object of this type has the semantics of the UBOUND quantity described in RFC 793." ::= { tcp 3 } Raghunarayan, Editor [Page 8] INTERNET-DRAFT Expires: December 2002 June 2002 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." ::= { tcp 5 } 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." ::= { 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." ::= { 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." ::= { tcp 8 } Raghunarayan, Editor [Page 9] INTERNET-DRAFT Expires: December 2002 June 2002 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." ::= { 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." ::= { tcp 11 } 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." ::= { 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)." ::= { tcp 14 } Raghunarayan, Editor [Page 10] INTERNET-DRAFT Expires: December 2002 June 2002 tcpOutRsts OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of TCP segments sent containing the RST flag." ::= { tcp 15 } -- { tcp 16 } was used to represent the ipv6TcpConnTable in RFC 2452, -- which has since been obsoleted. It MUST not be used. tcpHCInSegs OBJECT-TYPE SYNTAX Counter64 MAX-ACCESS read-only STATUS current DESCRIPTION "The total number of segments received, including those received in error, on systems that can receive more than 1 million TCP segments per second. This count includes segments received on currently established connections." ::= { 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, on systems that can transmit more than 1 million TCP segments per second." ::= { tcp 18 } tcpListenerTableLastChange OBJECT-TYPE SYNTAX TimeStamp MAX-ACCESS read-only STATUS current DESCRIPTION "The value of sysUpTime at the time of the last creation or deletion of an entry in the tcpListenerTable. If the number of entries has been unchanged since the last re-initialization of the local network management subsystem, then this object contains a zero value." ::= { tcp 19 } -- The TCP Connection table tcpConnectionTable OBJECT-TYPE SYNTAX SEQUENCE OF TcpConnectionEntry MAX-ACCESS not-accessible STATUS current Raghunarayan, Editor [Page 11] INTERNET-DRAFT Expires: December 2002 June 2002 DESCRIPTION "A table containing information about existing TCP connections. Note that unlike earlier TCP MIBs, there is a seperate table for connections in the LISTEN state." ::= { tcp 20 } 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, tcpConnectionRemAddress, tcpConnectionRemPort } ::= { tcpConnectionTable 1 } TcpConnectionEntry ::= SEQUENCE { tcpConnectionLocalAddressType InetAddressType, tcpConnectionLocalAddress InetAddress, tcpConnectionLocalPort InetPortNumber, tcpConnectionRemAddress InetAddress, tcpConnectionRemPort InetPortNumber, tcpConnectionState INTEGER, tcpConnectionInSegs Counter32, tcpConnectionOutSegs Counter32, tcpConnectionInOctets Counter32, tcpConnectionOutOctets Counter32, tcpConnectionHCInSegs Counter64, tcpConnectionHCOutSegs Counter64, tcpConnectionHCInOctets Counter64, tcpConnectionHCOutOctets Counter64, tcpConnectionStartTime TimeStamp, tcpConnectionProcess Unsigned32 } tcpConnectionLocalAddressType OBJECT-TYPE SYNTAX InetAddressType MAX-ACCESS not-accessible STATUS current DESCRIPTION "The address type of tcpConnectionLocalAddress. Only IPv4 and IPv6 addresses are expected." ::= { tcpConnectionEntry 1 } Raghunarayan, Editor [Page 12] INTERNET-DRAFT Expires: December 2002 June 2002 tcpConnectionLocalAddress OBJECT-TYPE SYNTAX InetAddress (SIZE(0..36)) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The local IP address for this TCP connection." ::= { tcpConnectionEntry 2 } tcpConnectionLocalPort OBJECT-TYPE SYNTAX InetPortNumber MAX-ACCESS not-accessible STATUS current DESCRIPTION "The local port number for this TCP connection." ::= { tcpConnectionEntry 3 } tcpConnectionRemAddress OBJECT-TYPE SYNTAX InetAddress (SIZE(0..36)) MAX-ACCESS not-accessible STATUS current DESCRIPTION "The remote IP address for this TCP connection." ::= { tcpConnectionEntry 4 } tcpConnectionRemPort OBJECT-TYPE SYNTAX InetPortNumber MAX-ACCESS not-accessible STATUS current DESCRIPTION "The remote port number for this TCP connection." ::= { tcpConnectionEntry 5 } tcpConnectionState OBJECT-TYPE SYNTAX INTEGER { closed(1), listen(2), -- do we need this here??? 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. Raghunarayan, Editor [Page 13] INTERNET-DRAFT Expires: December 2002 June 2002 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 6 } tcpConnectionInSegs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of segments, including control segments without payload and retransmitted segments, received on this connection." ::= { tcpConnectionEntry 7 } tcpConnectionOutSegs OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of segments, including control segments without payload and retransmitted segments, transmitted on this connection." ::= { tcpConnectionEntry 8 } tcpConnectionInOctets OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of octets, including the TCP header, received on this connection. This count includes retransmitted data." ::= { tcpConnectionEntry 9 } Raghunarayan, Editor [Page 14] INTERNET-DRAFT Expires: December 2002 June 2002 tcpConnectionOutOctets OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of octets, including the TCP header, transmitted on this connection. This count includes retransmitted data." ::= { tcpConnectionEntry 10 } tcpConnectionHCInSegs OBJECT-TYPE SYNTAX Counter64 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of segments, including control segments without payload and retransmitted segments, received on this connection. This is the 64-bit equivalent of the tcpConnectionInSegs counter." ::= { tcpConnectionEntry 11 } tcpConnectionHCOutSegs OBJECT-TYPE SYNTAX Counter64 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of segments, including control segments without payload and retransmitted segments, transmitted on this connection. This is the 64-bit equivalent of the tcpConnectionOutSegs counter." ::= { tcpConnectionEntry 12 } tcpConnectionHCInOctets OBJECT-TYPE SYNTAX Counter64 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of octets, including the TCP header, received on this connection. This count includes retransmitted data. This counter is the 64-bit equivalent of the tcpConnectionInOctets counter." ::= { tcpConnectionEntry 13 } tcpConnectionHCOutOctets OBJECT-TYPE SYNTAX Counter64 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of octets, including the TCP header, transmitted on this connection. This count includes retransmitted data. This counter is the 64-bit equivalent of the Raghunarayan, Editor [Page 15] INTERNET-DRAFT Expires: December 2002 June 2002 tcpConnectionOutOctets counter." ::= { tcpConnectionEntry 14 } tcpConnectionStartTime OBJECT-TYPE SYNTAX TimeStamp MAX-ACCESS read-only STATUS current DESCRIPTION "The value of sysUpTime at the time this connection was established. The value of this object will be zero - before the connection enters the established state, or - if the established state was entered prior to the last re-initialization of the local network management subsystem." ::= { tcpConnectionEntry 15 } 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 16 } -- 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). Raghunarayan, Editor [Page 16] INTERNET-DRAFT Expires: December 2002 June 2002 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: that 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 21 } 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 } TcpListenerEntry ::= SEQUENCE { tcpListenerLocalAddressType InetAddressType, tcpListenerLocalAddress InetAddress, tcpListenerLocalPort InetPortNumber, tcpListenerTimeOuts Counter32, tcpListenerEstablished Counter32, tcpListenerStartTime TimeStamp, tcpListenerProcess Unsigned32 } tcpListenerLocalAddressType OBJECT-TYPE SYNTAX InetAddressType MAX-ACCESS not-accessible STATUS current DESCRIPTION "The address type of tcpListenerLocalAddress. Only IPv4 and IPv6 addresses are expected, or unknown (0) if connection initiation to all local IP addresses are accepted. " ::= { tcpListenerEntry 1 } tcpListenerLocalAddress OBJECT-TYPE SYNTAX InetAddress (SIZE(0..36)) MAX-ACCESS not-accessible STATUS current Raghunarayan, Editor [Page 17] INTERNET-DRAFT Expires: December 2002 June 2002 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." ::= { tcpListenerEntry 2 } tcpListenerLocalPort OBJECT-TYPE SYNTAX InetPortNumber MAX-ACCESS not-accessible STATUS current DESCRIPTION "The local port number for this TCP connection." ::= { tcpListenerEntry 3 } tcpListenerTimeOuts OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of connection attempts to this endpoint which have failed due to timeout of the three-way handshake, i.e. the row was removed from the tcpConnectionTable but tcpConnectionState never moved from synReceived to established." ::= { tcpListenerEntry 4 } tcpListenerEstablished OBJECT-TYPE SYNTAX Counter32 MAX-ACCESS read-only STATUS current DESCRIPTION "The number of connections which have been established to this endpoint." ::= { tcpListenerEntry 5 } tcpListenerStartTime OBJECT-TYPE SYNTAX TimeStamp MAX-ACCESS read-only STATUS current DESCRIPTION "The value of sysUpTime at the time this listener was established. If the current state was entered prior to the last re-initialization of the local network management subsystem, then this object contains a zero value." ::= { tcpListenerEntry 6 } tcpListenerProcess OBJECT-TYPE SYNTAX Unsigned32 MAX-ACCESS read-only STATUS current Raghunarayan, Editor [Page 18] INTERNET-DRAFT Expires: December 2002 June 2002 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 7 } -- 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 19] INTERNET-DRAFT Expires: December 2002 June 2002 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 } tcpConnLocalPort OBJECT-TYPE SYNTAX Integer32 (0..65535) MAX-ACCESS read-only STATUS deprecated Raghunarayan, Editor [Page 20] INTERNET-DRAFT Expires: December 2002 June 2002 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." MODULE -- this module MANDATORY-GROUPS { tcpBaseGroup, tcpConnectionGroup } GROUP tcpListenerGroup DESCRIPTION "This group is mandatory for those systems supporting the tcpListenerTable." 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." GROUP tcpStatisticsGroup DESCRIPTION "This group is optional. It provides visibility for counters that some systems already implement." Raghunarayan, Editor [Page 21] INTERNET-DRAFT Expires: December 2002 June 2002 GROUP tcpHCStatisticsGroup DESCRIPTION "This group is mandatory for those systems which implement the tcpStatisticsGroup and 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 } 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 Raghunarayan, Editor [Page 22] INTERNET-DRAFT Expires: December 2002 June 2002 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 } tcpHCGroup OBJECT-GROUP OBJECTS { tcpHCInSegs, tcpHCOutSegs } STATUS current DESCRIPTION "The group of objects providing for counters of high speed TCP implementations." ::= { tcpMIBGroups 3 } tcpConnectionGroup OBJECT-GROUP OBJECTS { tcpConnectionState } STATUS current DESCRIPTION "The table of TCP connections." ::= { tcpMIBGroups 4 } tcpListenerGroup OBJECT-GROUP OBJECTS { tcpListenerTableLastChange } STATUS current DESCRIPTION "This group has objects providing general information about TCP listeners." ::= { tcpMIBGroups 5 } tcpStatisticsGroup OBJECT-GROUP OBJECTS { tcpConnectionInSegs, tcpConnectionOutSegs, tcpConnectionInOctets, tcpConnectionOutOctets, tcpConnectionStartTime, tcpConnectionProcess, tcpListenerTimeOuts, tcpListenerEstablished, tcpListenerStartTime, tcpListenerProcess } STATUS current DESCRIPTION "The segment and octet counters and other statistics specific to a TCP connection or listener." ::= { tcpMIBGroups 6 } Raghunarayan, Editor [Page 23] INTERNET-DRAFT Expires: December 2002 June 2002 tcpHCStatisticsGroup OBJECT-GROUP OBJECTS { tcpConnectionHCInSegs, tcpConnectionHCOutSegs, tcpConnectionHCInOctets, tcpConnectionHCOutOctets } STATUS current DESCRIPTION "The group of objects providing for statistics for listeners or connections on high speed TCP implementations." ::= { tcpMIBGroups 7 } END 5. Open Issues Does calculating the number of active TCP connections from the tcpConnectionTable have any operational concerns i.e. do we need a counter for the same? Or does the current counter, tcpCurrEstab (count of ESTABLISHED or CLOSE-WAIT connections), suffice? Are the current per-connection byte/segment counters appropriate? Other stats? [in optional conformance group] ConnSRTT? Number of half-open connections? Timeout for half-open connections? Should the tcpConnection*Octet counters include TCP header in the count as well? More HC counters? Do we need HC counter equivalents for tcpListenerTimeOuts and tcpListenerEstablished? How about a BITS object indicating the various TCP protocol features supported by this entity? Most of the timer values are represented in terms of sysUpTime i.e. TimeStamp. Is there an implementation concern here, with respect to, zeroing of values when the network management subsystem re-inits? Would DateAndTime be better, or would there be concerns of absence of clock hardware/issues with use of NTP for such cases? 6. 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. Raghunarayan, Editor [Page 24] INTERNET-DRAFT Expires: December 2002 June 2002 7. References [1] Daniele, M., Haberman, ., Routhier, S., and Schoenwaelder, J., "Textual Conventions for Internet Network Addresses", RFC 3291, May 2002. [2] Rose, M. and K. McCloghrie, "Management Information Base for Network Management of TCP/IP-based internets", RFC 1213, March 1991. [3] K. McCloghrie, "SNMPv2 Management Information Base for the Transmission Control Protocol using SMIv2", RFC 2012, November 1996. [4] Daniele, M., "IP Version 6 Management Information Base for the Transmission Control Protocol", RFC 2452, December 1998. [5] Postel, J., "Transmission Control Protocol - DARPA Internet Program Protocol Specification", STD 7, RFC 793, DARPA, September 1981. [6] Jacobson, V., "Congestion Avoidance and Control", SIGCOMM 1988, Stanford, California. [7] Harrington, D., Presuhn, R., and B. Wijnen, "An Architecture for Describing SNMP Management Frameworks", RFC 2571, April 1999. [8] Rose, M., and K. McCloghrie, "Structure and Identification of Management Information for TCP/IP-based Internets", STD 16, RFC 1155, May 1990. [9] Rose, M., and K. McCloghrie, "Concise MIB Definitions", STD 16, RFC 1212, March 1991. [10] Rose, M., "A Convention for Defining Traps for use with the SNMP", RFC 1215, March 1991. [11] 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. [12] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Textual Conventions for SMIv2", STD 58, RFC 2579, April 1999. [13] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Conformance Statements for SMIv2", STD 58, RFC 2580, April 1999. [14] Case, J., Fedor, M., Schoffstall, M., and J. Davin, "Simple Network Management Protocol", STD 15, RFC 1157, May 1990. Raghunarayan, Editor [Page 25] INTERNET-DRAFT Expires: December 2002 June 2002 [15] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Introduction to Community-based SNMPv2", RFC 1901, January 1996. [16] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Transport Mappings for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1906, January 1996. [17] Case, J., Harrington D., Presuhn R., and B. Wijnen, "Message Processing and Dispatching for the Simple Network Management Protocol (SNMP)", RFC 2572, April 1999. [18] Blumenthal, U., and B. Wijnen, "User-based Security Model (USM) for version 3 of the Simple Network Management Protocol (SNMPv3)", RFC 2574, April 1999. [19] Case, J., McCloghrie, K., Rose, M., and S. Waldbusser, "Protocol Operations for Version 2 of the Simple Network Management Protocol (SNMPv2)", RFC 1905, January 1996. [20] Levi, D., Meyer, P., and B. Stewart, "SNMPv3 Applications", RFC 2573, April 1999. [21] Wijnen, B., Presuhn, R., and K. McCloghrie, "View-based Access Control Model (VACM) for the Simple Network Management Protocol (SNMP)", RFC 2575, April 1999. [22] Case, J., Mundy, R., Partain, D., and B. Stewart, "Introduction to Version 3 of the Internet-standard Network Management Framework", RFC 2570, April 1999. [23] Krupczak, C., Saperia, J., "Definitions of System-Level Managed Objects for Applications", RFC 2287, February 1998. [24] Waldbusser, S., Grillo, P., "Host Resources MIB", RFC 2790, March 2000. 8. Security Considerations There are a number of management objects defined in this MIB that have a MAX-ACCESS clause of read-write and/or read-create. 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. There are a number of managed objects in this MIB that may contain sensitive information. These are: Raghunarayan, Editor [Page 26] INTERNET-DRAFT Expires: December 2002 June 2002 o The tcpConnectionLocalPort 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. 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. It is thus important to control even GET access to these objects and possibly to even encrypt the values of these object when sending them over the network via SNMP. Not all versions of SNMP provide features for such a secure environment. SNMPv1 by itself is not a secure environment. 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. It is recommended that the implementers consider the security features as provided by the SNMPv3 framework. Specifically, the use of the User-based Security Model RFC 2574 [18] and the View-based Access Control Model RFC 2575 [21] is recommended. It is then a customer/user responsibility to ensure that the SNMP entity giving access to an instance of this MIB, 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. 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: bkhabs@nc.rr.com Raghunarayan, Editor [Page 27] INTERNET-DRAFT Expires: December 2002 June 2002 Shawn A. Routhier, Wind River Email: sar@epilogue.com Juergen Schoenwalder, TU Braunschweig Email: schoenw@ibr.cs.tu-bs.de Dave Thaler, Microsoft Email: dthaler@windows.microsoft 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 11. Full Copyright Statement Copyright (C) The Internet Society (2002). 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 28]