RFC 4898
TCP Extended Statistics MIB
Pages: 75
Proposed Standard
Proposed Standard
Part 3 of 3 – Pages 41 to 75
tcpEStatsStackMSSRcvd OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value received in an MSS option, or zero if none."
REFERENCE
"RFC 1122, Requirements for Internet Hosts - Communication
Layers"
::= { tcpEStatsStackEntry 3 }
tcpEStatsStackWinScaleSent OBJECT-TYPE
SYNTAX Integer32 (-1..14)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of the transmitted window scale option if one was
sent; otherwise, a value of -1.
Note that if both tcpEStatsStackWinScaleSent and
tcpEStatsStackWinScaleRcvd are not -1, then Rcv.Wind.Scale
will be the same as this value and used to scale receiver
window announcements from the local host to the remote
host."
REFERENCE
"RFC 1323, TCP Extensions for High Performance"
::= { tcpEStatsStackEntry 4 }
tcpEStatsStackWinScaleRcvd OBJECT-TYPE
SYNTAX Integer32 (-1..14)
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of the received window scale option if one was
received; otherwise, a value of -1.
Note that if both tcpEStatsStackWinScaleSent and
tcpEStatsStackWinScaleRcvd are not -1, then Snd.Wind.Scale
will be the same as this value and used to scale receiver
window announcements from the remote host to the local
host."
REFERENCE
"RFC 1323, TCP Extensions for High Performance"
::= { tcpEStatsStackEntry 5 }
tcpEStatsStackTimeStamps OBJECT-TYPE
SYNTAX TcpEStatsNegotiated
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Enabled(1) if TCP timestamps have been negotiated on,
selfDisabled(2) if they are disabled or not implemented on
the local host, or peerDisabled(3) if not negotiated by the
remote hosts."
REFERENCE
"RFC 1323, TCP Extensions for High Performance"
::= { tcpEStatsStackEntry 6 }
tcpEStatsStackECN OBJECT-TYPE
SYNTAX TcpEStatsNegotiated
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Enabled(1) if Explicit Congestion Notification (ECN) has
been negotiated on, selfDisabled(2) if it is disabled or
not implemented on the local host, or peerDisabled(3) if
not negotiated by the remote hosts."
REFERENCE
"RFC 3168, The Addition of Explicit Congestion Notification
(ECN) to IP"
::= { tcpEStatsStackEntry 7 }
tcpEStatsStackWillSendSACK OBJECT-TYPE
SYNTAX TcpEStatsNegotiated
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Enabled(1) if the local host will send SACK options,
selfDisabled(2) if SACK is disabled or not implemented on
the local host, or peerDisabled(3) if the remote host did
not send the SACK-permitted option.
Note that SACK negotiation is not symmetrical. SACK can
enabled on one side of the connection and not the other."
REFERENCE
"RFC 2018, TCP Selective Acknowledgement Options"
::= { tcpEStatsStackEntry 8 }
tcpEStatsStackWillUseSACK OBJECT-TYPE
SYNTAX TcpEStatsNegotiated
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Enabled(1) if the local host will process SACK options,
selfDisabled(2) if SACK is disabled or not implemented on
the local host, or peerDisabled(3) if the remote host sends
duplicate ACKs without SACK options, or the local host
otherwise decides not to process received SACK options.
Unlike other TCP options, the remote data receiver cannot
explicitly indicate if it is able to generate SACK options.
When sending data, the local host has to deduce if the
remote receiver is sending SACK options. This object can
transition from Enabled(1) to peerDisabled(3) after the SYN
exchange.
Note that SACK negotiation is not symmetrical. SACK can
enabled on one side of the connection and not the other."
REFERENCE
"RFC 2018, TCP Selective Acknowledgement Options"
::= { tcpEStatsStackEntry 9 }
--
-- The following two objects reflect the current state of the
-- connection.
--
tcpEStatsStackState OBJECT-TYPE
SYNTAX INTEGER {
tcpESStateClosed(1),
tcpESStateListen(2),
tcpESStateSynSent(3),
tcpESStateSynReceived(4),
tcpESStateEstablished(5),
tcpESStateFinWait1(6),
tcpESStateFinWait2(7),
tcpESStateCloseWait(8),
tcpESStateLastAck(9),
tcpESStateClosing(10),
tcpESStateTimeWait(11),
tcpESStateDeleteTcb(12)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"An integer value representing the connection state from the
TCP State Transition Diagram.
The value listen(2) is included only for parallelism to the
old tcpConnTable, and SHOULD NOT be used because the listen
state in managed by the tcpListenerTable.
The value DeleteTcb(12) is included only for parallelism to
the tcpConnTable mechanism for terminating connections,
although this table does not permit writing."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsStackEntry 10 }
tcpEStatsStackNagle OBJECT-TYPE
SYNTAX TruthValue
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"True(1) if the Nagle algorithm is being used, else
false(2)."
REFERENCE
"RFC 1122, Requirements for Internet Hosts - Communication
Layers"
::= { tcpEStatsStackEntry 11 }
--
-- The following objects instrument the overall operation of
-- TCP congestion control and data retransmissions. These
-- instruments are sufficient to fit the actual performance to
-- an updated macroscopic performance model [RFC2581] [Mat97]
-- [Pad98].
--
tcpEStatsStackMaxSsCwnd OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum congestion window used during Slow Start, in
octets."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 12 }
tcpEStatsStackMaxCaCwnd OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum congestion window used during Congestion
Avoidance, in octets."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 13 }
tcpEStatsStackMaxSsthresh OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum slow start threshold, excluding the initial
value."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 14 }
tcpEStatsStackMinSsthresh OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The minimum slow start threshold."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 15 }
tcpEStatsStackInRecovery OBJECT-TYPE
SYNTAX INTEGER {
tcpESDataContiguous(1),
tcpESDataUnordered(2),
tcpESDataRecovery(3)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"An integer value representing the state of the loss
recovery for this connection.
tcpESDataContiguous(1) indicates that the remote receiver
is reporting contiguous data (no duplicate acknowledgments
or SACK options) and that there are no unacknowledged
retransmissions.
tcpESDataUnordered(2) indicates that the remote receiver is
reporting missing or out-of-order data (e.g., sending
duplicate acknowledgments or SACK options) and that there
are no unacknowledged retransmissions (because the missing
data has not yet been retransmitted).
tcpESDataRecovery(3) indicates that the sender has
outstanding retransmitted data that is still
unacknowledged."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 16 }
tcpEStatsStackDupAcksIn OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of duplicate ACKs received."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 17 }
tcpEStatsStackSpuriousFrDetected OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of acknowledgments reporting out-of-order
segments after the Fast Retransmit algorithm has already
retransmitted the segments. (For example as detected by the
Eifel algorithm).'"
REFERENCE
"RFC 3522, The Eifel Detection Algorithm for TCP"
::= { tcpEStatsStackEntry 18 }
tcpEStatsStackSpuriousRtoDetected OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of acknowledgments reporting segments that have
already been retransmitted due to a Retransmission Timeout."
::= { tcpEStatsStackEntry 19 }
--
-- The following optional objects instrument unusual protocol
-- events that probably indicate implementation problems in
-- the protocol or path.
--
tcpEStatsStackSoftErrors OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of segments that fail various consistency tests
during TCP input processing. Soft errors might cause the
segment to be discarded but some do not. Some of these soft
errors cause the generation of a TCP acknowledgment, while
others are silently discarded."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsStackEntry 21 }
tcpEStatsStackSoftErrorReason OBJECT-TYPE
SYNTAX INTEGER {
belowDataWindow(1),
aboveDataWindow(2),
belowAckWindow(3),
aboveAckWindow(4),
belowTSWindow(5),
aboveTSWindow(6),
dataCheckSum(7),
otherSoftError(8)
}
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"This object identifies which consistency test most recently
failed during TCP input processing. This object SHOULD be
set every time tcpEStatsStackSoftErrors is incremented. The
codes are as follows:
belowDataWindow(1) - All data in the segment is below
SND.UNA. (Normal for keep-alives and zero window probes).
aboveDataWindow(2) - Some data in the segment is above
SND.WND. (Indicates an implementation bug or possible
attack).
belowAckWindow(3) - ACK below SND.UNA. (Indicates that the
return path is reordering ACKs)
aboveAckWindow(4) - An ACK for data that we have not sent.
(Indicates an implementation bug or possible attack).
belowTSWindow(5) - TSecr on the segment is older than the
current TS.Recent (Normal for the rare case where PAWS
detects data reordered by the network).
aboveTSWindow(6) - TSecr on the segment is newer than the
current TS.Recent. (Indicates an implementation bug or
possible attack).
dataCheckSum(7) - Incorrect checksum. Note that this value
is intrinsically fragile, because the header fields used to
identify the connection may have been corrupted.
otherSoftError(8) - All other soft errors not listed
above."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsStackEntry 22 }
--
-- The following optional objects expose the detailed
-- operation of the congestion control algorithms.
--
tcpEStatsStackSlowStart OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of times the congestion window has been
increased by the Slow Start algorithm."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 23 }
tcpEStatsStackCongAvoid OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of times the congestion window has been
increased by the Congestion Avoidance algorithm."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 24 }
tcpEStatsStackOtherReductions OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of congestion window reductions made as a result
of anything other than AIMD congestion control algorithms.
Examples of non-multiplicative window reductions include
Congestion Window Validation [RFC2861] and experimental
algorithms such as Vegas [Bra94].
All window reductions MUST be counted as either
tcpEStatsPerfCongSignals or tcpEStatsStackOtherReductions."
REFERENCE
"RFC 2861, TCP Congestion Window Validation"
::= { tcpEStatsStackEntry 25 }
tcpEStatsStackCongOverCount OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of congestion events that were 'backed out' of
the congestion control state machine such that the
congestion window was restored to a prior value. This can
happen due to the Eifel algorithm [RFC3522] or other
algorithms that can be used to detect and cancel spurious
invocations of the Fast Retransmit Algorithm.
Although it may be feasible to undo the effects of spurious
invocation of the Fast Retransmit congestion events cannot
easily be backed out of tcpEStatsPerfCongSignals and
tcpEStatsPathPreCongSumCwnd, etc."
REFERENCE
"RFC 3522, The Eifel Detection Algorithm for TCP"
::= { tcpEStatsStackEntry 26 }
tcpEStatsStackFastRetran OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of invocations of the Fast Retransmit algorithm."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 27 }
tcpEStatsStackSubsequentTimeouts OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of times the retransmit timeout has expired after
the RTO has been doubled. See Section 5.5 of RFC 2988."
REFERENCE
"RFC 2988, Computing TCP's Retransmission Timer"
::= { tcpEStatsStackEntry 28 }
tcpEStatsStackCurTimeoutCount OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of times the retransmit timeout has
expired without receiving an acknowledgment for new data.
tcpEStatsStackCurTimeoutCount is reset to zero when new
data is acknowledged and incremented for each invocation of
Section 5.5 of RFC 2988."
REFERENCE
"RFC 2988, Computing TCP's Retransmission Timer"
::= { tcpEStatsStackEntry 29 }
tcpEStatsStackAbruptTimeouts OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of timeouts that occurred without any
immediately preceding duplicate acknowledgments or other
indications of congestion. Abrupt Timeouts indicate that
the path lost an entire window of data or acknowledgments.
Timeouts that are preceded by duplicate acknowledgments or
other congestion signals (e.g., ECN) are not counted as
abrupt, and might have been avoided by a more sophisticated
Fast Retransmit algorithm."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsStackEntry 30 }
tcpEStatsStackSACKsRcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of SACK options received."
REFERENCE
"RFC 2018, TCP Selective Acknowledgement Options"
::= { tcpEStatsStackEntry 31 }
tcpEStatsStackSACKBlocksRcvd OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of SACK blocks received (within SACK options)."
REFERENCE
"RFC 2018, TCP Selective Acknowledgement Options"
::= { tcpEStatsStackEntry 32 }
tcpEStatsStackSendStall OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of interface stalls or other sender local
resource limitations that are treated as congestion
signals."
::= { tcpEStatsStackEntry 33 }
tcpEStatsStackDSACKDups OBJECT-TYPE
SYNTAX ZeroBasedCounter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of duplicate segments reported to the local host
by D-SACK blocks."
REFERENCE
"RFC 2883, An Extension to the Selective Acknowledgement
(SACK) Option for TCP"
::= { tcpEStatsStackEntry 34 }
--
-- The following optional objects instrument path MTU
-- discovery.
--
tcpEStatsStackMaxMSS OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum MSS, in octets."
REFERENCE
"RFC 1191, Path MTU discovery"
::= { tcpEStatsStackEntry 35 }
tcpEStatsStackMinMSS OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The minimum MSS, in octets."
REFERENCE
"RFC 1191, Path MTU discovery"
::= { tcpEStatsStackEntry 36 }
--
-- The following optional initial value objects are useful for
-- conformance testing instruments on application progress and
-- consumed network resources.
--
tcpEStatsStackSndInitial OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Initial send sequence number. Note that by definition
tcpEStatsStackSndInitial never changes for a given
connection."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsStackEntry 37 }
tcpEStatsStackRecInitial OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"Initial receive sequence number. Note that by definition
tcpEStatsStackRecInitial never changes for a given
connection."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsStackEntry 38 }
--
-- The following optional objects instrument the senders
-- buffer usage, including any buffering in the application
-- interface to TCP and the retransmit queue. All 'buffer
-- memory' instruments are assumed to include OS data
-- structure overhead.
--
tcpEStatsStackCurRetxQueue OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of octets of data occupying the
retransmit queue."
::= { tcpEStatsStackEntry 39 }
tcpEStatsStackMaxRetxQueue OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum number of octets of data occupying the
retransmit queue."
::= { tcpEStatsStackEntry 40 }
tcpEStatsStackCurReasmQueue OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of octets of sequence space spanned by
the reassembly queue. This is generally the difference
between rcv.nxt and the sequence number of the right most
edge of the reassembly queue."
::= { tcpEStatsStackEntry 41 }
tcpEStatsStackMaxReasmQueue OBJECT-TYPE
SYNTAX Gauge32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum value of tcpEStatsStackCurReasmQueue"
::= { tcpEStatsStackEntry 42 }
-- ================================================================
--
-- Statistics for diagnosing interactions between
-- applications and TCP.
--
tcpEStatsAppTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsAppEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains objects that are useful for
determining if the application using TCP is
limiting TCP performance.
Entries are retained in this table for the number of
seconds indicated by the tcpEStatsConnTableLatency
object, after the TCP connection first enters the closed
state."
::= { tcpEStats 6 }
tcpEStatsAppEntry OBJECT-TYPE
SYNTAX TcpEStatsAppEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in this table has information about the
characteristics of each active and recently closed TCP
connection."
INDEX { tcpEStatsConnectIndex }
::= { tcpEStatsAppTable 1 }
TcpEStatsAppEntry ::= SEQUENCE {
tcpEStatsAppSndUna Counter32,
tcpEStatsAppSndNxt Unsigned32,
tcpEStatsAppSndMax Counter32,
tcpEStatsAppThruOctetsAcked ZeroBasedCounter32,
tcpEStatsAppHCThruOctetsAcked ZeroBasedCounter64,
tcpEStatsAppRcvNxt Counter32,
tcpEStatsAppThruOctetsReceived ZeroBasedCounter32,
tcpEStatsAppHCThruOctetsReceived ZeroBasedCounter64,
tcpEStatsAppCurAppWQueue Gauge32,
tcpEStatsAppMaxAppWQueue Gauge32,
tcpEStatsAppCurAppRQueue Gauge32,
tcpEStatsAppMaxAppRQueue Gauge32
}
--
-- The following objects provide throughput statistics for the
-- connection including sequence numbers and elapsed
-- application data. These permit direct observation of the
-- applications progress, in terms of elapsed data delivery
-- and elapsed time.
--
tcpEStatsAppSndUna OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of SND.UNA, the oldest unacknowledged sequence
number.
Note that SND.UNA is a TCP state variable that is congruent
to Counter32 semantics."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsAppEntry 1 }
tcpEStatsAppSndNxt OBJECT-TYPE
SYNTAX Unsigned32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of SND.NXT, the next sequence number to be sent.
Note that tcpEStatsAppSndNxt is not monotonic (and thus not
a counter) because TCP sometimes retransmits lost data by
pulling tcpEStatsAppSndNxt back to the missing data."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsAppEntry 2 }
tcpEStatsAppSndMax OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The farthest forward (right most or largest) SND.NXT value.
Note that this will be equal to tcpEStatsAppSndNxt except
when tcpEStatsAppSndNxt is pulled back during recovery."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsAppEntry 3 }
tcpEStatsAppThruOctetsAcked OBJECT-TYPE
SYNTAX ZeroBasedCounter32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets for which cumulative acknowledgments
have been received. Note that this will be the sum of
changes to tcpEStatsAppSndUna."
::= { tcpEStatsAppEntry 4 }
tcpEStatsAppHCThruOctetsAcked OBJECT-TYPE
SYNTAX ZeroBasedCounter64
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets for which cumulative acknowledgments
have been received, on systems that can receive more than
10 million bits per second. Note that this will be the sum
of changes in tcpEStatsAppSndUna."
::= { tcpEStatsAppEntry 5 }
tcpEStatsAppRcvNxt OBJECT-TYPE
SYNTAX Counter32
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The value of RCV.NXT. The next sequence number expected on
an incoming segment, and the left or lower edge of the
receive window.
Note that RCV.NXT is a TCP state variable that is congruent
to Counter32 semantics."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsAppEntry 6 }
tcpEStatsAppThruOctetsReceived OBJECT-TYPE
SYNTAX ZeroBasedCounter32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets for which cumulative acknowledgments
have been sent. Note that this will be the sum of changes
to tcpEStatsAppRcvNxt."
::= { tcpEStatsAppEntry 7 }
tcpEStatsAppHCThruOctetsReceived OBJECT-TYPE
SYNTAX ZeroBasedCounter64
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The number of octets for which cumulative acknowledgments
have been sent, on systems that can transmit more than 10
million bits per second. Note that this will be the sum of
changes in tcpEStatsAppRcvNxt."
::= { tcpEStatsAppEntry 8 }
tcpEStatsAppCurAppWQueue OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of octets of application data buffered
by TCP, pending first transmission, i.e., to the left of
SND.NXT or SndMax. This data will generally be transmitted
(and SND.NXT advanced to the left) as soon as there is an
available congestion window (cwnd) or receiver window
(rwin). This is the amount of data readily available for
transmission, without scheduling the application. TCP
performance may suffer if there is insufficient queued
write data."
::= { tcpEStatsAppEntry 11 }
tcpEStatsAppMaxAppWQueue OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum number of octets of application data buffered
by TCP, pending first transmission. This is the maximum
value of tcpEStatsAppCurAppWQueue. This pair of objects can
be used to determine if insufficient queued data is steady
state (suggesting insufficient queue space) or transient
(suggesting insufficient application performance or
excessive CPU load or scheduler latency)."
::= { tcpEStatsAppEntry 12 }
tcpEStatsAppCurAppRQueue OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The current number of octets of application data that has
been acknowledged by TCP but not yet delivered to the
application."
::= { tcpEStatsAppEntry 13 }
tcpEStatsAppMaxAppRQueue OBJECT-TYPE
SYNTAX Gauge32
UNITS "octets"
MAX-ACCESS read-only
STATUS current
DESCRIPTION
"The maximum number of octets of application data that has
been acknowledged by TCP but not yet delivered to the
application."
::= { tcpEStatsAppEntry 14 }
-- ================================================================
--
-- Controls for Tuning TCP
--
tcpEStatsTuneTable OBJECT-TYPE
SYNTAX SEQUENCE OF TcpEStatsTuneEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"This table contains per-connection controls that can
be used to work around a number of common problems that
plague TCP over some paths. All can be characterized as
limiting the growth of the congestion window so as to
prevent TCP from overwhelming some component in the
path.
Entries are retained in this table for the number of
seconds indicated by the tcpEStatsConnTableLatency
object, after the TCP connection first enters the closed
state."
::= { tcpEStats 7 }
tcpEStatsTuneEntry OBJECT-TYPE
SYNTAX TcpEStatsTuneEntry
MAX-ACCESS not-accessible
STATUS current
DESCRIPTION
"Each entry in this table is a control that can be used to
place limits on each active TCP connection."
INDEX { tcpEStatsConnectIndex }
::= { tcpEStatsTuneTable 1 }
TcpEStatsTuneEntry ::= SEQUENCE {
tcpEStatsTuneLimCwnd Unsigned32,
tcpEStatsTuneLimSsthresh Unsigned32,
tcpEStatsTuneLimRwin Unsigned32,
tcpEStatsTuneLimMSS Unsigned32
}
tcpEStatsTuneLimCwnd OBJECT-TYPE
SYNTAX Unsigned32
UNITS "octets"
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"A control to set the maximum congestion window that may be
used, in octets."
REFERENCE
"RFC 2581, TCP Congestion Control"
::= { tcpEStatsTuneEntry 1 }
tcpEStatsTuneLimSsthresh OBJECT-TYPE
SYNTAX Unsigned32
UNITS "octets"
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"A control to limit the maximum queue space (in octets) that
this TCP connection is likely to occupy during slowstart.
It can be implemented with the algorithm described in
RFC 3742 by setting the max_ssthresh parameter to twice
tcpEStatsTuneLimSsthresh.
This algorithm can be used to overcome some TCP performance
problems over network paths that do not have sufficient
buffering to withstand the bursts normally present during
slowstart."
REFERENCE
"RFC 3742, Limited Slow-Start for TCP with Large Congestion
Windows"
::= { tcpEStatsTuneEntry 2 }
tcpEStatsTuneLimRwin OBJECT-TYPE
SYNTAX Unsigned32
UNITS "octets"
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"A control to set the maximum window advertisement that may
be sent, in octets."
REFERENCE
"RFC 793, Transmission Control Protocol"
::= { tcpEStatsTuneEntry 3 }
tcpEStatsTuneLimMSS OBJECT-TYPE
SYNTAX Unsigned32
UNITS "octets"
MAX-ACCESS read-write
STATUS current
DESCRIPTION
"A control to limit the maximum segment size in octets, that
this TCP connection can use."
REFERENCE
"RFC 1191, Path MTU discovery"
::= { tcpEStatsTuneEntry 4 }
-- ================================================================
--
-- TCP Extended Statistics Notifications Group
--
tcpEStatsEstablishNotification NOTIFICATION-TYPE
OBJECTS {
tcpEStatsConnectIndex
}
STATUS current
DESCRIPTION
"The indicated connection has been accepted
(or alternatively entered the established state)."
::= { tcpEStatsNotifications 1 }
tcpEStatsCloseNotification NOTIFICATION-TYPE
OBJECTS {
tcpEStatsConnectIndex
}
STATUS current
DESCRIPTION
"The indicated connection has left the
established state"
::= { tcpEStatsNotifications 2 }
-- ================================================================
--
-- Conformance Definitions
--
tcpEStatsCompliances OBJECT IDENTIFIER
::= { tcpEStatsConformance 1 }
tcpEStatsGroups OBJECT IDENTIFIER
::= { tcpEStatsConformance 2 }
--
-- Compliance Statements
--
tcpEStatsCompliance MODULE-COMPLIANCE
STATUS current
DESCRIPTION
"Compliance statement for all systems that implement TCP
extended statistics."
MODULE -- this module
MANDATORY-GROUPS {
tcpEStatsListenerGroup,
tcpEStatsConnectIdGroup,
tcpEStatsPerfGroup,
tcpEStatsPathGroup,
tcpEStatsStackGroup,
tcpEStatsAppGroup
}
GROUP tcpEStatsListenerHCGroup
DESCRIPTION
"This group is mandatory for all systems that can
wrap the values of the 32-bit counters in
tcpEStatsListenerGroup in less than one hour."
GROUP tcpEStatsPerfOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsPerfHCGroup
DESCRIPTION
"This group is mandatory for systems that can
wrap the values of the 32-bit counters in
tcpEStatsPerfGroup in less than one hour.
Note that any system that can attain 10 Mb/s
can potentially wrap 32-Bit Octet counters in
under one hour."
GROUP tcpEStatsPathOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsPathHCGroup
DESCRIPTION
"This group is mandatory for systems that can
wrap the values of the 32-bit counters in
tcpEStatsPathGroup in less than one hour.
Note that any system that can attain 10 Mb/s
can potentially wrap 32-Bit Octet counters in
under one hour."
GROUP tcpEStatsStackOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsAppHCGroup
DESCRIPTION
"This group is mandatory for systems that can
wrap the values of the 32-bit counters in
tcpEStatsStackGroup in less than one hour.
Note that any system that can attain 10 Mb/s
can potentially wrap 32-Bit Octet counters in
under one hour."
GROUP tcpEStatsAppOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsTuneOptionalGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsNotificationsGroup
DESCRIPTION
"This group is optional for all systems."
GROUP tcpEStatsNotificationsCtlGroup
DESCRIPTION
"This group is mandatory for systems that include the
tcpEStatsNotificationGroup."
::= { tcpEStatsCompliances 1 }
-- ================================================================
--
-- Units of Conformance
--
tcpEStatsListenerGroup OBJECT-GROUP
OBJECTS {
tcpEStatsListenerTableLastChange,
tcpEStatsListenerStartTime,
tcpEStatsListenerSynRcvd,
tcpEStatsListenerInitial,
tcpEStatsListenerEstablished,
tcpEStatsListenerAccepted,
tcpEStatsListenerExceedBacklog,
tcpEStatsListenerCurConns,
tcpEStatsListenerMaxBacklog,
tcpEStatsListenerCurBacklog,
tcpEStatsListenerCurEstabBacklog
}
STATUS current
DESCRIPTION
"The tcpEStatsListener group includes objects that
provide valuable statistics and debugging
information for TCP Listeners."
::= { tcpEStatsGroups 1 }
tcpEStatsListenerHCGroup OBJECT-GROUP
OBJECTS {
tcpEStatsListenerHCSynRcvd,
tcpEStatsListenerHCInitial,
tcpEStatsListenerHCEstablished,
tcpEStatsListenerHCAccepted,
tcpEStatsListenerHCExceedBacklog
}
STATUS current
DESCRIPTION
"The tcpEStatsListenerHC group includes 64-bit
counters in tcpEStatsListenerTable."
::= { tcpEStatsGroups 2 }
tcpEStatsConnectIdGroup OBJECT-GROUP
OBJECTS {
tcpEStatsConnTableLatency,
tcpEStatsConnectIndex
}
STATUS current
DESCRIPTION
"The tcpEStatsConnectId group includes objects that
identify TCP connections and control how long TCP
connection entries are retained in the tables."
::= { tcpEStatsGroups 3 }
tcpEStatsPerfGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPerfSegsOut, tcpEStatsPerfDataSegsOut,
tcpEStatsPerfDataOctetsOut,
tcpEStatsPerfSegsRetrans,
tcpEStatsPerfOctetsRetrans, tcpEStatsPerfSegsIn,
tcpEStatsPerfDataSegsIn,
tcpEStatsPerfDataOctetsIn,
tcpEStatsPerfElapsedSecs,
tcpEStatsPerfElapsedMicroSecs,
tcpEStatsPerfStartTimeStamp, tcpEStatsPerfCurMSS,
tcpEStatsPerfPipeSize, tcpEStatsPerfMaxPipeSize,
tcpEStatsPerfSmoothedRTT, tcpEStatsPerfCurRTO,
tcpEStatsPerfCongSignals, tcpEStatsPerfCurCwnd,
tcpEStatsPerfCurSsthresh, tcpEStatsPerfTimeouts,
tcpEStatsPerfCurRwinSent,
tcpEStatsPerfMaxRwinSent,
tcpEStatsPerfZeroRwinSent,
tcpEStatsPerfCurRwinRcvd,
tcpEStatsPerfMaxRwinRcvd,
tcpEStatsPerfZeroRwinRcvd
}
STATUS current
DESCRIPTION
"The tcpEStatsPerf group includes those objects that
provide basic performance data for a TCP connection."
::= { tcpEStatsGroups 4 }
tcpEStatsPerfOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPerfSndLimTransRwin,
tcpEStatsPerfSndLimTransCwnd,
tcpEStatsPerfSndLimTransSnd,
tcpEStatsPerfSndLimTimeRwin,
tcpEStatsPerfSndLimTimeCwnd,
tcpEStatsPerfSndLimTimeSnd
}
STATUS current
DESCRIPTION
"The tcpEStatsPerf group includes those objects that
provide basic performance data for a TCP connection."
::= { tcpEStatsGroups 5 }
tcpEStatsPerfHCGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPerfHCDataOctetsOut,
tcpEStatsPerfHCDataOctetsIn
}
STATUS current
DESCRIPTION
"The tcpEStatsPerfHC group includes 64-bit
counters in the tcpEStatsPerfTable."
::= { tcpEStatsGroups 6 }
tcpEStatsPathGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlPath,
tcpEStatsPathRetranThresh,
tcpEStatsPathNonRecovDAEpisodes,
tcpEStatsPathSumOctetsReordered,
tcpEStatsPathNonRecovDA
}
STATUS current
DESCRIPTION
"The tcpEStatsPath group includes objects that
control the creation of the tcpEStatsPathTable,
and provide information about the path
for each TCP connection."
::= { tcpEStatsGroups 7 }
tcpEStatsPathOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPathSampleRTT, tcpEStatsPathRTTVar,
tcpEStatsPathMaxRTT, tcpEStatsPathMinRTT,
tcpEStatsPathSumRTT, tcpEStatsPathCountRTT,
tcpEStatsPathMaxRTO, tcpEStatsPathMinRTO,
tcpEStatsPathIpTtl, tcpEStatsPathIpTosIn,
tcpEStatsPathIpTosOut,
tcpEStatsPathPreCongSumCwnd,
tcpEStatsPathPreCongSumRTT,
tcpEStatsPathPostCongSumRTT,
tcpEStatsPathPostCongCountRTT,
tcpEStatsPathECNsignals,
tcpEStatsPathDupAckEpisodes, tcpEStatsPathRcvRTT,
tcpEStatsPathDupAcksOut, tcpEStatsPathCERcvd,
tcpEStatsPathECESent
}
STATUS current
DESCRIPTION
"The tcpEStatsPath group includes objects that
provide additional information about the path
for each TCP connection."
::= { tcpEStatsGroups 8 }
tcpEStatsPathHCGroup OBJECT-GROUP
OBJECTS {
tcpEStatsPathHCSumRTT
}
STATUS current
DESCRIPTION
"The tcpEStatsPathHC group includes 64-bit
counters in the tcpEStatsPathTable."
::= { tcpEStatsGroups 9 }
tcpEStatsStackGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlStack,
tcpEStatsStackActiveOpen, tcpEStatsStackMSSSent,
tcpEStatsStackMSSRcvd, tcpEStatsStackWinScaleSent,
tcpEStatsStackWinScaleRcvd,
tcpEStatsStackTimeStamps, tcpEStatsStackECN,
tcpEStatsStackWillSendSACK,
tcpEStatsStackWillUseSACK, tcpEStatsStackState,
tcpEStatsStackNagle, tcpEStatsStackMaxSsCwnd,
tcpEStatsStackMaxCaCwnd,
tcpEStatsStackMaxSsthresh,
tcpEStatsStackMinSsthresh,
tcpEStatsStackInRecovery, tcpEStatsStackDupAcksIn,
tcpEStatsStackSpuriousFrDetected,
tcpEStatsStackSpuriousRtoDetected
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
control the creation of the tcpEStatsStackTable,
and provide information about the operation of
algorithms used within TCP."
::= { tcpEStatsGroups 10 }
tcpEStatsStackOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsStackSoftErrors,
tcpEStatsStackSoftErrorReason,
tcpEStatsStackSlowStart, tcpEStatsStackCongAvoid,
tcpEStatsStackOtherReductions,
tcpEStatsStackCongOverCount,
tcpEStatsStackFastRetran,
tcpEStatsStackSubsequentTimeouts,
tcpEStatsStackCurTimeoutCount,
tcpEStatsStackAbruptTimeouts,
tcpEStatsStackSACKsRcvd,
tcpEStatsStackSACKBlocksRcvd,
tcpEStatsStackSendStall, tcpEStatsStackDSACKDups,
tcpEStatsStackMaxMSS, tcpEStatsStackMinMSS,
tcpEStatsStackSndInitial,
tcpEStatsStackRecInitial,
tcpEStatsStackCurRetxQueue,
tcpEStatsStackMaxRetxQueue,
tcpEStatsStackCurReasmQueue,
tcpEStatsStackMaxReasmQueue
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
provide additional information about the operation of
algorithms used within TCP."
::= { tcpEStatsGroups 11 }
tcpEStatsAppGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlApp,
tcpEStatsAppSndUna, tcpEStatsAppSndNxt,
tcpEStatsAppSndMax, tcpEStatsAppThruOctetsAcked,
tcpEStatsAppRcvNxt,
tcpEStatsAppThruOctetsReceived
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
control the creation of the tcpEStatsAppTable,
and provide information about the operation of
algorithms used within TCP."
::= { tcpEStatsGroups 12 }
tcpEStatsAppHCGroup OBJECT-GROUP
OBJECTS {
tcpEStatsAppHCThruOctetsAcked,
tcpEStatsAppHCThruOctetsReceived
}
STATUS current
DESCRIPTION
"The tcpEStatsStackHC group includes 64-bit
counters in the tcpEStatsStackTable."
::= { tcpEStatsGroups 13 }
tcpEStatsAppOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsAppCurAppWQueue,
tcpEStatsAppMaxAppWQueue,
tcpEStatsAppCurAppRQueue,
tcpEStatsAppMaxAppRQueue
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
provide additional information about how applications
are interacting with each TCP connection."
::= { tcpEStatsGroups 14 }
tcpEStatsTuneOptionalGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlTune,
tcpEStatsTuneLimCwnd, tcpEStatsTuneLimSsthresh,
tcpEStatsTuneLimRwin, tcpEStatsTuneLimMSS
}
STATUS current
DESCRIPTION
"The tcpEStatsConnState group includes objects that
control the creation of the tcpEStatsConnectionTable,
which can be used to set tuning parameters
for each TCP connection."
::= { tcpEStatsGroups 15 }
tcpEStatsNotificationsGroup NOTIFICATION-GROUP
NOTIFICATIONS {
tcpEStatsEstablishNotification,
tcpEStatsCloseNotification
}
STATUS current
DESCRIPTION
"Notifications sent by a TCP extended statistics agent."
::= { tcpEStatsGroups 16 }
tcpEStatsNotificationsCtlGroup OBJECT-GROUP
OBJECTS {
tcpEStatsControlNotify
}
STATUS current
DESCRIPTION
"The tcpEStatsNotificationsCtl group includes the
object that controls the creation of the events
in the tcpEStatsNotificationsGroup."
::= { tcpEStatsGroups 17 }
END
5. Security Considerations
There are a number of management objects defined in this MIB module with 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. These are the tables and objects and their sensitivity/vulnerability: * Changing tcpEStatsConnTableLatency or any of the control objects in the tcpEStatsControl group (tcpEStatsControlPath, tcpEStatsControlStack, tcpEStatsControlApp, tcpEStatsControlTune) may affect the correctness of other management applications accessing this MIB. Generally, local policy should only permit limited write access to these controls (e.g., only by one management station or only during system configuration). * The objects in the tcpEStatsControlTune group (tcpEStatsTuneLimCwnd, tcpEStatsTuneLimSsthresh, tcpEStatsTuneLimRwin) can be used to limit resources consumed by TCP connections or to limit TCP throughput. An attacker might manipulate these objects to reduce performance to levels below the minimum acceptable for a particular application. 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: * All objects which expose TCP sequence numbers (tcpEStatsAppSndUna, tcpEStatsAppSndNxt, tcpEStatsAppSndMax, tcpEStatsStackSndInitial, tcpEStatsAppRcvNxt, and tcpEStatsStackRecInitial) might make it easier for an attacker to forge in sequence TCP segments to disrupt TCP connections. * Nearly all objects in this (or any other) MIB may be used to estimate traffic volumes, which may reveal unanticipated information about an organization to the outside world. 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.6. IANA Considerations
The MIB module in this document uses the following IANA-assigned OBJECT IDENTIFIER values recorded in the SMI Numbers registry: Descriptor OBJECT IDENTIFIER value ------------ ----------------------- tcpEStatsMIB { mib-2 156 }7. Normative References
[RFC791] Postel, J., "Internet Protocol", STD 5, RFC 791, September 1981. [RFC793] Postel, J., "Transmission Control Protocol", STD 7, RFC 793, September 1981. [RFC1122] Braden, R., Ed., "Requirements for Internet Hosts - Communication Layers", STD 3, RFC 1122, October 1989. [RFC1191] Mogul, J. and S. Deering, "Path MTU discovery", RFC 1191, November 1990. [RFC1323] Jacobson, V., Braden, R., and D. Borman, "TCP Extensions for High Performance", RFC 1323, May 1992. [RFC2018] Mathis, M., Mahdavi, J., Floyd, S., and A. Romanow, "TCP Selective Acknowledgment Options", RFC 2018, October 1996. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997.
[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", RFC 2579, STD 58, April 1999. [RFC2580] McCloghrie, K., Perkins, D., Schoenwaelder, J., Case, J., Rose, M., and S. Waldbusser, "Conformance Statements for SMIv2", RFC 2580, STD 58, April 1999. [RFC2581] Allman, M., Paxson, V., and W. Stevens, "TCP Congestion Control", RFC 2581, April 1999. [RFC2856] Bierman, A., McCloghrie, K., and R. Presuhn, "Textual Conventions for Additional High Capacity Data Types", RFC 2856, June 2000. [RFC2883] Floyd, S., Mahdavi, J., Mathis, M., and M. Podolsky, "An Extension to the Selective Acknowledgement (SACK) Option for TCP", RFC 2883, July 2000. [RFC2988] Paxson, V. and M. Allman, "Computing TCP's Retransmission Timer", RFC 2988, November 2000. [RFC3168] Ramakrishnan, K., Floyd, S., and D. Black, "The Addition of Explicit Congestion Notification (ECN) to IP", RFC 3168, September 2001. [RFC3517] Blanton, E., Allman, M., Fall, K., and L. Wang, "A Conservative Selective Acknowledgment (SACK)-based Loss Recovery Algorithm for TCP", RFC 3517, April 2003. [RFC4022] Raghunarayan, R., Ed., "Management Information Base for the Transmission Control Protocol (TCP)", RFC 4022, March 2005. [RFC4502] Waldbusser, S., "Remote Network Monitoring Management Information Base Version 2", RFC 4502, May 2006.
8. Informative References
[Mat97] M. Mathis, J. Semke, J. Mahdavi, T. Ott, "The Macroscopic Behavior of the TCP Congestion Avoidance Algorithm", Computer Communication Review, volume 27, number 3, July 1997. [Bra94] Brakmo, L., O'Malley, S., "TCP Vegas, New Techniques for Congestion Detection and Avoidance", SIGCOMM'94, London, pp 24-35, October 1994. [Edd06] Eddy, W., "TCP SYN Flooding Attacks and Common Mitigations", Work in Progress, May 2007. [POSIX] Portable Operating System Interface, IEEE Std 1003.1 [Pad98] Padhye, J., Firoiu, V., Towsley, D., Kurose, J., "Modeling TCP Throughput: A Simple Model and its Empirical Validation", SIGCOMM'98. [Web100] Mathis, M., J. Heffner, R. Reddy, "Web100: Extended TCP Instrumentation for Research, Education and Diagnosis", ACM Computer Communications Review, Vol 33, Num 3, July 2003. [RFC2861] Handley, M., Padhye, J., and S. Floyd, "TCP Congestion Window Validation", RFC 2861, June 2000. [RFC3260] Grossman, D., "New Terminology and Clarifications for Diffserv", RFC 3260, April 2002. [RFC3410] Case, J., Mundy, R., Partain, D. and B. Stewart, "Introduction and Applicability Statements for Internet- Standard Management Framework", RFC 3410, December 2002. [RFC3522] Ludwig, R. and M. Meyer, "The Eifel Detection Algorithm for TCP", RFC 3522, April 2003. [RFC3742] Floyd, S., "Limited Slow-Start for TCP with Large Congestion Windows", RFC 3742, March 2004. [RFC4614] Duke M., Braden, R., Eddy, W., Blanton, E. "A Roadmap for Transmission Control Protocol (TCP) Specification Documents", RFC 4614, September 2006.
9. Contributors
The following people contributed text that was incorporated into this document: Jon Saperia <saperia@jdscons.com> converted Web100 internal documentation into a true MIB. Some of the objects in this document were moved from an early version of the TCP-MIB by Bill Fenner, et al. Some of the object descriptions are based on an earlier unpublished document by Jeff Semke.10. Acknowledgments
This document is a product of the Web100 project (www.web100.org), a joint effort of Pittsburgh Supercomputing Center (www.psc.edu), National Center for Atmospheric Research (www.ncar.ucar.edu), and National Center for Supercomputer Applications (www.ncsa.edu). It would not have been possible without all of the hard work by the entire Web100 team, especially Peter O'Neal, who read and reread the entire document several times; Janet Brown and Marla Meehl, who patiently managed the unmanageable. The Web100 project would not have been successful without all of the early adopters who suffered our bugs to provide many good suggestions and insights into their needs for TCP instrumentation. Web100 was supported by the National Science Foundation under Grant No. 0083285 and a research grant from Cisco Systems. We would also like to thank all of the people who built experimental implementations of this MIB from early versions and provided us with constructive feedback: Glenn Turner at AARnet, Kristine Adamson at IBM, and Xinyan Zan at Microsoft. And last, but not least, we would like to thank Dan Romascanu, our "MIB Doctor" and Bert Wijnen, the Operations Area Director, for patiently steering us through the MIB review process.
Authors' Addresses
Matt Mathis Pittsburgh Supercomputing Center 300 S. Craig St. Pittsburgh, PA 15213 Phone: 412-268-4960 EMail: mathis@psc.edu John Heffner Pittsburgh Supercomputing Center 300 S. Craig St. Pittsburgh, PA 15213 Phone: 412-268-4960 EMail: jheffner@psc.edu Rajiv Raghunarayan Cisco Systems Inc. San Jose, CA 95134 Phone: 408 853 9612 EMail: raraghun@cisco.com
Full Copyright Statement Copyright (C) The IETF Trust (2007). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM 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. Intellectual Property The IETF takes no position regarding the validity or scope of any Intellectual Property Rights 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; nor does it represent that it has made any independent effort to identify any such rights. Information on the procedures with respect to rights in RFC documents can be found in BCP 78 and BCP 79. Copies of IPR disclosures made to the IETF Secretariat 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 implementers or users of this specification can be obtained from the IETF on-line IPR repository at http://www.ietf.org/ipr. The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights that may cover technology that may be required to implement this standard. Please address the information to the IETF at ietf-ipr@ietf.org. Acknowledgement Funding for the RFC Editor function is currently provided by the Internet Society.