SCALAR OBJECTS

Name	Type	Access	OID	Description
1 tcpRtoAlgorithm	INTEGER Value Label/Meaning 1 other 2 constant 3 rsre 4 vanj 5 rfc2988	ReadOnly	.1.3.6.1.2.1.6.1	The algorithm used to determine the timeout value used for retransmitting unacknowledged octets.
2 tcpRtoMin	INTEGER32 Legal values: 0 .. 2147483647	ReadOnly	.1.3.6.1.2.1.6.2	The minimum value permitted by a TCP implementation for the retransmission timeout, measured in milliseconds. More refined semantics for objects of this type depend on the algorithm used to determine the retransmission timeout; in particular, the IETF standard algorithm rfc2988(5) provides a minimum value.
3 tcpRtoMax	INTEGER32 Legal values: 0 .. 2147483647	ReadOnly	.1.3.6.1.2.1.6.3	The maximum value permitted by a TCP implementation for the retransmission timeout, measured in milliseconds. More refined semantics for objects of this type depend on 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).
4 tcpMaxConn	INTEGER32 Legal values: -1 , 0 .. 2147483647	ReadOnly	.1.3.6.1.2.1.6.4	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.
5 tcpActiveOpens	COUNTER	ReadOnly	.1.3.6.1.2.1.6.5	The number of times that TCP connections have made a direct transition to the SYN-SENT state from the CLOSED state. Discontinuities in the value of this counter are indicated via discontinuities in the value of sysUpTime.
6 tcpPassiveOpens	COUNTER	ReadOnly	.1.3.6.1.2.1.6.6	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 are indicated via discontinuities in the value of sysUpTime.
7 tcpAttemptFails	COUNTER	ReadOnly	.1.3.6.1.2.1.6.7	The number of times that 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 that TCP connections have made a direct transition to the LISTEN state from the SYN-RCVD state. Discontinuities in the value of this counter are indicated via discontinuities in the value of sysUpTime.
8 tcpEstabResets	COUNTER	ReadOnly	.1.3.6.1.2.1.6.8	The number of times that 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 are indicated via discontinuities in the value of sysUpTime.
9 tcpCurrEstab	GAUGE	ReadOnly	.1.3.6.1.2.1.6.9	The number of TCP connections for which the current state is either ESTABLISHED or CLOSE-WAIT.
10 tcpInSegs	COUNTER	ReadOnly	.1.3.6.1.2.1.6.10	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 are indicated via discontinuities in the value of sysUpTime.
11 tcpOutSegs	COUNTER	ReadOnly	.1.3.6.1.2.1.6.11	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 are indicated via discontinuities in the value of sysUpTime.
12 tcpRetransSegs	COUNTER	ReadOnly	.1.3.6.1.2.1.6.12	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 are indicated via discontinuities in the value of sysUpTime.
14 tcpInErrs	COUNTER	ReadOnly	.1.3.6.1.2.1.6.14	The total number of segments received in error (e.g., bad TCP checksums). Discontinuities in the value of this counter are indicated via discontinuities in the value of sysUpTime.
15 tcpOutRsts	COUNTER	ReadOnly	.1.3.6.1.2.1.6.15	The number of TCP segments sent containing the RST flag. Discontinuities in the value of this counter are indicated via discontinuities in the value of sysUpTime.
17 tcpHCInSegs	COUNTER64	ReadOnly	.1.3.6.1.2.1.6.17	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 are indicated via discontinuities in the value of sysUpTime.
18 tcpHCOutSegs	COUNTER64	ReadOnly	.1.3.6.1.2.1.6.18	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 are indicated via discontinuities in the value of sysUpTime.

TABLE OBJECTS

Table tcpConnectionTable

Table Name	tcpConnectionTable
In MIB	TCP-MIB
Registered at OID	.1.3.6.1.2.1.6.19
Table 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.
Row 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.

tcpConnectionTable Indexes:

Name	Type	Access	Description
1 tcpConnectionLocalAddressType	INTEGER InetAddressType (ENUM list below)	NoAccess	Note: this object is based on the InetAddressType TEXTUAL-CONVENTION. The address type of tcpConnectionLocalAddress.
2 tcpConnectionLocalAddress	OCTETSTR Legal Lengths: 0 .. 255 InetAddress	NoAccess	Note: this object is based on the InetAddress TEXTUAL-CONVENTION. 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 should be careful not to create entries that would result in OIDs with more than 128 subidentifiers; otherwise the information cannot be accessed by using SNMPv1, SNMPv2c, or SNMPv3.
3 tcpConnectionLocalPort	UNSIGNED32 Legal values: 0 .. 65535 InetPortNumber	NoAccess	Note: this object is based on the InetPortNumber TEXTUAL-CONVENTION. The local port number for this TCP connection.
4 tcpConnectionRemAddressType	INTEGER InetAddressType (ENUM list below)	NoAccess	Note: this object is based on the InetAddressType TEXTUAL-CONVENTION. The address type of tcpConnectionRemAddress.
5 tcpConnectionRemAddress	OCTETSTR Legal Lengths: 0 .. 255 InetAddress	NoAccess	Note: this object is based on the InetAddress TEXTUAL-CONVENTION. 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 should be careful not to create entries that would result in OIDs with more than 128 subidentifiers; otherwise the information cannot be accessed by using SNMPv1, SNMPv2c, or SNMPv3.
6 tcpConnectionRemPort	UNSIGNED32 Legal values: 0 .. 65535 InetPortNumber	NoAccess	Note: this object is based on the InetPortNumber TEXTUAL-CONVENTION. The remote port number for this TCP connection.

Other tcpConnectionTable Columns:

Name	Type	Access	Description
7 tcpConnectionState	INTEGER Value Label/Meaning 1 closed 2 listen 3 synSent 4 synReceived 5 established 6 finWait1 7 finWait2 8 closeWait 9 lastAck 10 closing 11 timeWait 12 deleteTCB	ReadWrite	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 that 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 the TCB (as defined in [RFC793]) of the corresponding connection on the managed node is deleted, 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).
8 tcpConnectionProcess	UNSIGNED32	ReadOnly	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.

Table tcpListenerTable

Table Name	tcpListenerTable
In MIB	TCP-MIB
Registered at OID	.1.3.6.1.2.1.6.20
Table 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 a tcpListenerLocalAddressType of unknown (0) and a tcpListenerLocalAddress of ''h (a zero-length octet-string). 2. An application that is willing to accept only IPv4 or IPv6 datagrams is represented by a tcpListenerLocalAddressType of the appropriate address type and a tcpListenerLocalAddress of '0.0.0.0' or '::' respectively. 3. An application that is 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 as 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)).
Row Description	A conceptual row of the tcpListenerTable containing information about a particular TCP listener.

tcpListenerTable Indexes:

Name	Type	Access	Description
1 tcpListenerLocalAddressType	INTEGER InetAddressType (ENUM list below)	NoAccess	Note: this object is based on the InetAddressType TEXTUAL-CONVENTION. The address type of tcpListenerLocalAddress. The value should be unknown (0) if connection initiations to all local IP addresses are accepted.
2 tcpListenerLocalAddress	OCTETSTR Legal Lengths: 0 .. 255 InetAddress	NoAccess	Note: this object is based on the InetAddress TEXTUAL-CONVENTION. The local IP address for this TCP connection. The value of this object can be represented in three possible ways, depending on the characteristics of the listening application: 1. For an application willing to accept both IPv4 and IPv6 datagrams, the value of this object must be ''h (a zero-length octet-string), with the value of the corresponding tcpListenerLocalAddressType object being unknown (0). 2. For an application willing to accept only IPv4 or IPv6 datagrams, the value of this object must be '0.0.0.0' or '::' respectively, with tcpListenerLocalAddressType representing the appropriate address type. 3. For an application which is listening for data destined only to a specific IP address, the value of this object is the specific local address, with tcpListenerLocalAddressType representing the appropriate address type. As this object is used in the index for the tcpListenerTable, implementors should be careful not to create entries that would result in OIDs with more than 128 subidentifiers; otherwise the information cannot be accessed, using SNMPv1, SNMPv2c, or SNMPv3.
3 tcpListenerLocalPort	UNSIGNED32 Legal values: 0 .. 65535 InetPortNumber	NoAccess	Note: this object is based on the InetPortNumber TEXTUAL-CONVENTION. The local port number for this TCP connection.

Other tcpListenerTable Columns:

Name	Type	Access	Description
4 tcpListenerProcess	UNSIGNED32	ReadOnly	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.

DEPRECATED OR OBSOLETE OR HISTORIC OBJECTS

NOTIFICATIONS

TEXTUAL CONVENTIONS

These TEXTUAL-CONVENTIONS are used in other parts of the document above. They are SNMP's way of defining a datatype that is used repeatedly by other MIB objects. Any implementation implementing objects that use one of these definitions must follow its DESCRIPTION clause as well as the DESCRIPTION clause of the object itself.

Name	Type	Description
InetPortNumber	UNSIGNED32	Represents a 16 bit port number of an Internet transport layer protocol. Port numbers are assigned by IANA. A current list of all assignments is available from . The value zero is object-specific and must be defined as part of the description of any object that uses this syntax. Examples of the usage of zero might include situations where a port number is unknown, or when the value zero is used as a wildcard in a filter.
InetAddress	OCTETSTR	Denotes a generic Internet address. An InetAddress value is always interpreted within the context of an InetAddressType value. Every usage of the InetAddress textual convention is required to specify the InetAddressType object that provides the context. It is suggested that the InetAddressType object be logically registered before the object(s) that use the InetAddress textual convention, if they appear in the same logical row. The value of an InetAddress object must always be consistent with the value of the associated InetAddressType object. Attempts to set an InetAddress object to a value inconsistent with the associated InetAddressType must fail with an inconsistentValue error. When this textual convention is used as the syntax of an index object, there may be issues with the limit of 128 sub-identifiers specified in SMIv2, STD 58. In this case, the object definition MUST include a 'SIZE' clause to limit the number of potential instance sub-identifiers; otherwise the applicable constraints MUST be stated in the appropriate conceptual row DESCRIPTION clauses, or in the surrounding documentation if there is no single DESCRIPTION clause that is appropriate.
InetAddressType	INTEGER Value Label/Meaning 0 unknown 1 ipv4 2 ipv6 3 ipv4z 4 ipv6z 16 dns	A value that represents a type of Internet address. unknown(0) An unknown address type. This value MUST be used if the value of the corresponding InetAddress object is a zero-length string. It may also be used to indicate an IP address that is not in one of the formats defined below. ipv4(1) An IPv4 address as defined by the InetAddressIPv4 textual convention. ipv6(2) An IPv6 address as defined by the InetAddressIPv6 textual convention. ipv4z(3) A non-global IPv4 address including a zone index as defined by the InetAddressIPv4z textual convention. ipv6z(4) A non-global IPv6 address including a zone index as defined by the InetAddressIPv6z textual convention. dns(16) A DNS domain name as defined by the InetAddressDNS textual convention. Each definition of a concrete InetAddressType value must be accompanied by a definition of a textual convention for use with that InetAddressType. To support future extensions, the InetAddressType textual convention SHOULD NOT be sub-typed in object type definitions. It MAY be sub-typed in compliance statements in order to require only a subset of these address types for a compliant implementation. Implementations must ensure that InetAddressType objects and any dependent objects (e.g., InetAddress objects) are consistent. An inconsistentValue error must be generated if an attempt to change an InetAddressType object would, for example, lead to an undefined InetAddress value. In particular, InetAddressType/InetAddress pairs must be changed together if the address type changes (e.g., from ipv6(2) to ipv4(1)).

TREE VIEW

Tree view generated by running: snmptranslate -Tp TCP-MIB::tcp