Network Working Group W. Sun
Internet-Draft SJTU
Intended status: Standards Track G. Zhang
Expires: November 29, 2010 CATR
May 28, 2010
Label Switched Path (LSP) Data Path Delay Metric in Generalized MPLS/
MPLS-TE Networks
draft-ietf-ccamp-dpm-00.txt
Abstract
When setting up a label switched path (LSP) in Generalized MPLS and
MPLS/TE networks, the completion of the signaling process does not
necessarily mean that the cross connection along the LSP have been
programmed accordingly and in a timely manner. Meanwhile, the
completion of signaling process may be used by applications as
indication that data path has become usable. The existence of this
delay and the possible failure of cross connection programming, if
not properly treated, will result in data loss or even application
failure. Characterization of this performance can thus help
designers to improve the application model and to build more robust
applications. This document defines a series of performance metrics
to evaluate the availability of data path in the signaling process.
Status of this Memo
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This Internet-Draft will expire on November 29, 2010.
Copyright Notice
Copyright (c) 2010 IETF Trust and the persons identified as the
document authors. All rights reserved.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Conventions Used in This Document . . . . . . . . . . . . . . 6
3. Overview of Performance Metrics . . . . . . . . . . . . . . . 7
4. Terms used in this document . . . . . . . . . . . . . . . . . 8
5. A singleton Definition for RRFD . . . . . . . . . . . . . . . 9
5.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 9
5.2. Metric Name . . . . . . . . . . . . . . . . . . . . . . . 9
5.3. Metric Parameters . . . . . . . . . . . . . . . . . . . . 9
5.4. Metric Units . . . . . . . . . . . . . . . . . . . . . . . 9
5.5. Definition . . . . . . . . . . . . . . . . . . . . . . . . 10
5.6. Discussion . . . . . . . . . . . . . . . . . . . . . . . . 10
5.7. Methodologies . . . . . . . . . . . . . . . . . . . . . . 11
6. A singleton Definition for RSRD . . . . . . . . . . . . . . . 12
6.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 12
6.2. Metric Name . . . . . . . . . . . . . . . . . . . . . . . 12
6.3. Metric Parameters . . . . . . . . . . . . . . . . . . . . 12
6.4. Metric Units . . . . . . . . . . . . . . . . . . . . . . . 12
6.5. Definition . . . . . . . . . . . . . . . . . . . . . . . . 13
6.6. Discussion . . . . . . . . . . . . . . . . . . . . . . . . 13
6.7. Methodologies . . . . . . . . . . . . . . . . . . . . . . 14
7. A singleton Definition for PRFD . . . . . . . . . . . . . . . 15
7.1. Motivation . . . . . . . . . . . . . . . . . . . . . . . . 15
7.2. Metric Name . . . . . . . . . . . . . . . . . . . . . . . 15
7.3. Metric Parameters . . . . . . . . . . . . . . . . . . . . 15
7.4. Metric Units . . . . . . . . . . . . . . . . . . . . . . . 15
7.5. Definition . . . . . . . . . . . . . . . . . . . . . . . . 15
7.6. Discussion . . . . . . . . . . . . . . . . . . . . . . . . 16
7.7. Methodologies . . . . . . . . . . . . . . . . . . . . . . 16
8. A Definition for Samples of Data Path Delay . . . . . . . . . 18
8.1. Metric Name . . . . . . . . . . . . . . . . . . . . . . . 18
8.2. Metric Parameters . . . . . . . . . . . . . . . . . . . . 18
8.3. Metric Units . . . . . . . . . . . . . . . . . . . . . . . 18
8.4. Definition . . . . . . . . . . . . . . . . . . . . . . . . 18
8.5. Discussion . . . . . . . . . . . . . . . . . . . . . . . . 19
8.6. Methodologies . . . . . . . . . . . . . . . . . . . . . . 19
8.7. Typical testing cases . . . . . . . . . . . . . . . . . . 19
8.7.1. With No LSP in the Network . . . . . . . . . . . . . . 19
8.7.2. With a Number of LSPs in the Network . . . . . . . . . 20
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9. Some Statistics Definitions for Metrics to Report . . . . . . 21
9.1. The Minimum of Metric . . . . . . . . . . . . . . . . . . 21
9.2. The Median of Metric . . . . . . . . . . . . . . . . . . . 21
9.3. The percentile of Metric . . . . . . . . . . . . . . . . . 21
9.4. The Failure Probability . . . . . . . . . . . . . . . . . 21
10. Security Considerations . . . . . . . . . . . . . . . . . . . 22
11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 23
12. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 24
13. References . . . . . . . . . . . . . . . . . . . . . . . . . . 25
13.1. Normative References . . . . . . . . . . . . . . . . . . . 25
13.2. Informative References . . . . . . . . . . . . . . . . . . 25
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 26
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1. Introduction
Ideally, the completion of the signaling process means that the
signaled label switched path (LSP) is available and is ready to carry
traffic. However, in actual implementations, vendors may choose to
program the cross connection in a pipelined manner, so that the
overall LSP provisioning delay can be reduced. In such situations,
the data path may not be available instantly after the signaling
process completes. Implementation deficiency may also cause the
inconsistency in between the signaling process and data path
provisioning. For example, if the data plane failed to program the
cross connection accordingly but does not manage to report this to
the control plane, the signaling process may complete successfully
while the corresponding data path will never become functional at
all.
On the other hand, the completion of the signaling process may be
used in many cases as indication of data path availability. For
example, when invoking through User Network Interface (UNI), a client
device or an application may use the reception of the correct RESV
message as indication that data path is fully functional and start to
transmit traffic. This will results in data loss or even application
failure.
Although RSVP(-TE) specifications have suggested that the cross
connections are programmed before signaling messages are propagated
upstream, it is still worthwhile to verify the conformance of an
implementation and measure the delay, when necessary.
This document defines a series of performance metrics to evaluate the
availability of data path when the signaling process completes. The
metrics defined in this document complements the control plane
metrics defined in [RFC5814]. They can be used to verify the
conformance of implementations against related specifications, as
elaborated in [I-D.shiomoto-ccamp-switch-programming]. They also can
be used to build more robust applications.
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2. Conventions Used in This Document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119].
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3. Overview of Performance Metrics
In this memo, we define three performance metrics to characterize the
performance of data path provisioning with GMPLS/MPLS-TE signaling.
These metrics complement the metrics defined in [RFC5814], in the
sense that the completion of the signaling process for a Label
Switched Path (LSP) and the programming of cross connections along
the LSP may not be consistent. The performance metrics in [RFC5814]
characterize the performance of LSP provisioning from the pure
signaling point of view, while the metric in this document takes into
account the validity of the data path.
The three metrics are:
o RRFD - the delay between RESV message received by ingress node and
forward data path becomes available.
o RSRD - the delay between RESV message sent by egress node and
reverse data path becomes available.
o PRFD - the delay between PATH message received by egress node and
forward data path becomes available.
As in [RFC5814], we continue to use the structures and notions
introduced and discussed in the IPPM Framework document, [RFC2330]
[RFC2679] [RFC2681]. The reader is assumed to be familiar with the
notions in those documents. The readers are assumed to be familiar
with the definitions in [RFC5814] as well.
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4. Terms used in this document
o Forward data path - the data path from the ingress to the egress.
Instances of forward data path include the data path of a uni-
directional LSP and data path from the ingress node to the egress
node in a bidirectional LSP.
o Reverse data path - the data path from the egress to the ingress
in a bidirectional LSP.
o Error free signal - data plane specific indication of availability
of the data path. For example, for packet switched interfaces,
the reception of the first error free packet from one side of the
LSP to the other can be used as the error free signal. For SDH/
SONET cross connects, the disappearance of alarm can be used as
the error free signal. Through out this document, we will use the
"error free signal" as a general term. An implementations must
choose a proper data path signal that is specific to the data path
technology being tested.
o Ingress/egress node - in this memo, an ingress/egress node means a
measurement endpoint with both control plane and data plane
features. Typically, the control plane part on an ingress/egress
node interact with the control plane of the network under test.
The data plane part of an ingress/egress node will generate data
path signals and send the signal to the data plane of the network
under test, or receive data path signals from the network under
test.
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5. A singleton Definition for RRFD
This part defines a metric for forward data path delay when an LSP is
setup.
As described in [I-D.shiomoto-ccamp-switch-programming], the
completion of the RSVP-TE signaling process does not necessarily mean
that the cross connections along the LSP being setup are in place and
ready to carry traffic. This metric defines the time difference
between the reception of RESV message by the ingress node and the
completion of the cross connection programming along the forward data
path.
5.1. Motivation
RRFD is useful for several reasons:
o For the reasons described in
[I-D.shiomoto-ccamp-switch-programming], the data path may not be
available instantly after the completion of the RSVP-TE signaling
process. The delay itself is part of the implementation
performance.
o The completion of the signaling process may be used by application
designers as indication of data path availability. The existence
of this delay and the potential failure of cross connection
programming, if not properly treated, will result in data loss or
application failure. The typical value of this delay can thus
help designers to improve the application model.
5.2. Metric Name
RRFD
5.3. Metric Parameters
o ID0, the ingress LSR ID
o ID1, the egress LSR ID
o T, a time when the setup is attempted
5.4. Metric Units
Either a real number of milli-seconds or undefined.
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5.5. Definition
For a real number dT, RRFD from ingress node ID0 to egress node ID1
at T is dT means that ingress node ID0 send a PATH message to egress
node ID1 and the last bit of the corresponding RESV message is
received by ingress node ID0 at T, and an error free signal is
received by egress node ID1 by using a data plane specific test
pattern at T+dT.
5.6. Discussion
The following issues are likely to come up in practice:
o The accuracy of RRFD depends on the clock resolution of both the
ingress node and egress node. Clock synchronization between the
ingress node and egress node is required.
o The accuracy of RRFD is also dependent on how the error free
signal is received and may differ significantly when the underline
data plane technology is different. For instance, for an LSP
between a pair of Ethernet interfaces, the ingress node (sometimes
the tester) may use a rate based method to verify the availability
of the data path and use the reception of the first error free
frame as the error free signal. In this case, the interval
between two successive frames has a significant impact on
accuracy. It is RECOMMENDED that the ingress node uses small
intervals, under the condition that the injected traffic does not
exceed the capacity of the forward data path. The value of the
interval MUST be reported.
o The accuracy of RRFD is also dependent on the time needed to
propagate the error free signal from the ingress node to the
egress node. A typical value of propagating the error free signal
from the ingress node to the egress node under the same
measurement setup MAY be reported. The methodology to obtain such
values is outside the scope of this document.
o It is possible that under some implementations, a node may program
the cross connection before it sends PATH message further
downstream and the data path may be available before a RESV
message reaches the ingress node. In such cases, RRFD can be a
negetive value. It is RECOMMENDED that PRFD measurement is
carried out to further characterize the forward data path delay
when a negetive RRFD value is observed.
o If error free signal is received by the egress node before PATH
message is sent, an error MUST be reported and the measurement
SHOULD terminate.
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o If the corresponding RESV message is received, but no error free
signal is received by the egress node within a reasonable period
of time, RRFD MUST be treated as undefined. The value of the
threshold MUST be reported.
o If the LSP setup fails, RRFD MUST NOT be counted.
5.7. Methodologies
Generally the methodology would proceed as follows:
o Make sure that the network has enough resource to set up the
requested LSP.
o Start the data path measurement and/or monitoring procedures on
the ingress node and egress node. If error free signal is
received by the egress node before PATH message is sent, report an
error and terminate the mmeasurement.
o At the ingress node, form the PATH message according to the LSP
requirements and send the message towards the egress node.
o Upon receiving the last bit of the corresponding RESV message,
take the time stamp (T1) on the ingress node as soon as possible.
o When an error free signal is observed on the egress node, take the
time stamp (T2) as soon as possible. An estimate of RRFD (T2 -
T1) can be computed.
o If the corresponding RESV message arrives, but no error free
signal is received within a reasonable period of time by the
ingress node, RRFD is deemed to be undefined.
o If the LSP setup fails, RRFD is not counted.
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6. A singleton Definition for RSRD
This part defines a metric for reverse data path delay when an LSP is
setup.
As described in [I-D.shiomoto-ccamp-switch-programming], the
completion of the RSVP-TE signaling process does not necessarily mean
that the cross connections along the LSP being setup are in place and
ready to carry traffic. This metric defines the time difference
between the completion of the signaling process and the completion of
the cross connection programming along the reverse data path. This
metric MAY be used together with RRFD to characterize the data path
delay of a bidirectional LSP.
6.1. Motivation
RSRD is useful for several reasons:
o For the reasons described in
[I-D.shiomoto-ccamp-switch-programming], the data path may not be
available instantly after the completion of the RSVP-TE signaling
process. The delay itself is part of the implementation
performance.
o The completion of the signaling process may be used by application
designers as indication of data path availability. The existence
of this delay and the possible failure of cross connection
programming, if not properly treated, will result in data loss or
application failure. The typical value of this delay can thus
help designers to improve the application model.
6.2. Metric Name
RSRD
6.3. Metric Parameters
o ID0, the ingress LSR ID
o ID1, the egress LSR ID
o T, a time when the setup is attempted
6.4. Metric Units
Either a real number of milli-seconds or undefined.
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6.5. Definition
For a real number dT, RSRD from ingress node ID0 to egress node ID1
at T is dT means that ingress node ID0 send a PATH message to egress
node ID1 and the last bit of the corresponding RESV message is sent
by egress node ID1 at T, and an error free signal is received by the
ingress node ID0 using a data plane specific test pattern at T+dT.
6.6. Discussion
The following issues are likely to come up in practice:
o The accuracy of RSRD depends on the clock resolution of both the
ingress node and egress node. And clock synchronization between
the ingress node and egress node is required.
o The accuracy of RSRD is also dependent on how the error free
signal is received and may differ significantly when the underline
data plane technology is different. For instance, for an LSP
between a pair of Ethernet interfaces, the egress node (sometimes
the tester) may use a rate based method to verify the availability
of the data path and use the reception of the first error free
frame as the error free signal. In this case, the interval
between two successive frames has a significant impact on
accuracy. It is RECOMMENDED that in this case the egress node
uses small intervals, under the condition that the injected
traffic does not exceed the capacity of the reverse data path.
The value of the interval MUST be reported.
o The accuracy of RSRD is also dependent on the time needed to
propagate the error free signal from the egress node to the
ingress node. A typical value of propagating the error free
signal from the egress node to the ingress node under the same
measurement setup MAY be reported. The methodology to obtain such
values is outside the scope of this document.
o If the corresponding RESV message is sent, but no error free
signal is received by the ingress node within a reasonable period
of time, RSRD MUST be treated as undefined. The value of the
threshold MUST be reported.
o If error free signal is received before PATH message is sent, an
error MUST be reported and the measurement SHOULD terminate.
o If the LSP setup fails, RSRD MUST NOT be counted.
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6.7. Methodologies
Generally the methodology would proceed as follows:
o Make sure that the network has enough resource to set up the
requested LSPs.
o Start the data path measurement and/or monitoring procedures on
the ingress node and egress node. If error free signal is
received by the ingress node before PATH message is sent, report
an error and terminate the mmeasurement.
o At the ingress node, form the PATH message according to the LSP
requirements and send the message towards the egress node.
o Upon sending the last bit of the corresponding RESV message, take
the time stamp (T1) on the egress node as soon as possible.
o When an error free signal is observed on the ingress node, take
the time stamp (T2) as soon as possible. An estimate of RSRD
(T2-T1) can be computed.
o If the LSP setup fails, RSRD is not counted.
o If no error free signal is received within a reasonable period of
time by the ingress node, RSRD is deemed to be undefined.
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7. A singleton Definition for PRFD
This part defines a metric for forward data path delay when an LSP is
setup.
In an RSVP-TE implementation, when setting up an LSP, each node may
choose to program the cross connection before it sends PATH message
further downstream. In this case, the forward data path may become
available before the signaling process completes, ie. before the RESV
reaches the ingress node. This metric can be used to identify such
implementation practice and give useful information to application
designers.
7.1. Motivation
PRFD is useful for the following reasons:
o PRFD can be used to identify an RSVP-TE implementation practice,
in which cross connections are programmed before PATH message is
sent downtream.
o The value of PRFD may also help application designers to fine tune
their application model.
7.2. Metric Name
PRFD
7.3. Metric Parameters
o ID0, the ingress LSR ID
o ID1, the egress LSR ID
o T, a time when the setup is attempted
7.4. Metric Units
Either a real number of milli-seconds or undefined.
7.5. Definition
For a real number dT, PRFD from ingress node ID0 to egress node ID1
at T is dT means that ingress node ID0 send a PATH message to egress
node ID1 and the last bit of the PATH message is received by egress
node ID1 at T, and an error free signal is received by the egress
node ID1 using a data plane specific test pattern at T+dT.
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7.6. Discussion
The following issues are likely to come up in practice:
o The accuracy of PRFD depends on the clock resolution of the egress
node. And clock synchronization between the ingress node and
egress node is not required.
o The accuracy of PRFD is also dependent on how the error free
signal is received and may differ significantly when the underline
data plane technology is different. For instance, for an LSP
between a pair of Ethernet interfaces, the egress node (sometimes
the tester) may use a rate based method to verify the availability
of the data path and use the reception of the first error free
frame as the error free signal. In this case, the interval
between two successive frames has a significant impact on
accuracy. It is RECOMMENDED that in this case the ingress node
uses small intervals, under the condition that the injected
traffic does not exceed the capacity of the forward data path.
The value of the interval MUST be reported.
o The accuracy of PRFD is also dependent on the time needed to
propagate the error free signal from the ingress node to the
egress node. A typical value of propagating the error free signal
from the ingress node to the egress node under the same
measurement setup MAY be reported. The methodology to obtain such
values is outside the scope of this document.
o If error free signal is received before PATH message is sent, an
error MUST be reported and the measurement SHOULD terminate.
o If the LSP setup fails, PRFD MUST NOT be counted.
o This metric SHOULD be used together with RRFD. It is RECOMMENDED
that PRFD measurement is carried out after a negetive RRFD value
has already been observed.
7.7. Methodologies
Generally the methodology would proceed as follows:
o Make sure that the network has enough resource to set up the
requested LSPs.
o Start the data path measurement and/or monitoring procedures on
the ingress node and egress node. If error free signal is
received by the egress node before PATH message is sent, report an
error and terminate the mmeasurement.
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o At the ingress node, form the PATH message according to the LSP
requirements and send the message towards the egress node.
o Upon receiving the last bit of the PATH message, take the time
stamp (T1) on the egress node as soon as possible.
o When an error free signal is observed on the egress node, take the
time stamp (T2) as soon as possible. An estimate of PRFD (T2-T1)
can be computed.
o If the LSP setup fails, PRFD is not counted.
o If no error free signal is received within a reasonable period of
time by the egress node, PRFD is deemed to be undefined.
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8. A Definition for Samples of Data Path Delay
In Section Section 5, Section 6 and Section 7, we define the
singleton metrics of data path delay. Now we define how to get one
particular sample of such delay. Sampling is to select a particular
potion of singleton values of the given parameters. Like in
[RFC2330], we use Poisson sampling as an example.
8.1. Metric Name
Type <X> Data path delay sample, where X is either RRFD, RSRD or
PRFD.
8.2. Metric Parameters
o ID0, the ingress LSR ID
o ID1, the egress LSR ID
o T0, a time
o Tf, a time
o Lambda, a rate in the reciprocal seconds
o Th, LSP holding time
o Td, the maximum waiting time for successful LSP setup
o Ts, the maximum waiting time for error free signal
8.3. Metric Units
A sequence of pairs; the elements of each pair are:
o T, a time when setup is attempted
o dT, either a real number of milli-seconds or undefined
8.4. Definition
Given T0, Tf, and lambda, compute a pseudo-random Poisson process
beginning at or before T0, with average arrival rate lambda, and
ending at or after Tf. Those time values greater than or equal to T0
and less than or equal to Tf are then selected. At each of the times
in this process, we obtain the value of data path delay sample of
type <X> at this time. The value of the sample is the sequence made
up of the resulting <time, type <X> data path delay> pairs. If there
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are no such pairs, the sequence is of length zero and the sample is
said to be empty.
8.5. Discussion
The following issues are likely to come up in practice:
o The parameters lambda, Th and Td should be carefully chosen, as
explained in the discussions for LSP setup delay.
o The parameter Ts should be carefully chosen and MUST be reported
along with the LSP forward/reverse data path delay sample.
o Note that for online or passive measurements, the holding time of
an LSP is determined by actual traffic, hence in this case Th is
not an input parameter.
8.6. Methodologies
Generally the methodology would proceed as follows:
o The selection of specific times, using the specified Poisson
arrival process, and
o Set up the LSP and obtain the value of type <X> data path delay
o Release the LSP after Th, and wait for the next Poisson arrival
process
8.7. Typical testing cases
8.7.1. With No LSP in the Network
8.7.1.1. Motivation
Data path delay with no LSP in the network is important because this
reflects the inherent delay of a device implementation. The minimum
value provides an indication of the delay that will likely be
experienced when an LSP data path is configured under light traffic
load.
8.7.1.2. Methodologies
Make sure that there is no LSP in the network, and proceed with the
methodologies described in Section 8.6.
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8.7.2. With a Number of LSPs in the Network
8.7.2.1. Motivation
Data path delay with a number of LSPs in the network is important
because it reflects the performance of an operational network with
considerable load. This delay may vary significantly as the number
of existing LSPs varies. It can be used as a scalability metric of a
device implementation.
8.7.2.2. Methodologies
Setup the required number of LSPs, and wait until the network reaches
a stable state, and then proceed with the methodologies described in
Section 8.6.
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9. Some Statistics Definitions for Metrics to Report
Given the samples of the performance metric, we now offer several
statistics of these samples to report. From these statistics, we can
draw some useful conclusions of a GMPLS network. The value of these
metrics is either a real number, or an undefined number of
milliseconds. In the following discussion, we only consider the
finite values.
9.1. The Minimum of Metric
The minimum of metric is the minimum of all the dT values in the
sample. In computing this, undefined values SHOULD be treated as
infinitely large. Note that this means that the minimum could thus
be undefined if all the dT values are undefined. In addition, the
metric minimum SHOULD be set to undefined if the sample is empty.
9.2. The Median of Metric
Metric median is the median of the dT values in the given sample. In
computing the median, the undefined values MUST NOT be counted in.
9.3. The percentile of Metric
Given a metric and a percent X between 0% and 100%, the Xth
percentile of all the dT values in the sample. In addition, the
percentile is undefined if the sample is empty.
Example: suppose we take a sample and the results are: Stream1 =
<<T1, 100 msec>, <T2, 110 msec>, <T3, undefined>, <T4, 90 msec>,
<T5,500 msec>>. Then the 50th percentile would be 110 msec, since 90
msec and 100 msec are smaller, and 110 and 500 msec are larger
(undefined values are not counted in).
9.4. The Failure Probability
In the process of LSP setup/release, it may fail for some reason.
The failure probability is the ratio of the unsuccessful times to the
total times.
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10. Security Considerations
In the control plane, since the measurement endpoints must be
conformant to signaling specifications and behave as normal signaling
endpoints, it will not incur other security issues than normal LSP
provisioning. However, the measurement parameters must be carefully
selected so that the measurements inject trivial amounts of
additional traffic into the networks they measure. If they inject
"too much" traffic, they can skew the results of the measurement, and
in extreme cases cause congestion and denial of service.
In the data plane, the measurement endpoint MUST use a signal that is
consistent with what is specified in the control plane. For example,
in a packet switched case, the traffic injected into the data plane
MUST NOT exceed the specified rate in the corresponding LSP setup
request. In a wavelength switched case, the measurement endpoint
MUST use the specified or negotiated lambda with appropriate power.
The security considerations pertaining to the original RSVP protocol
[RFC2205] and its TE extensions [RFC3209] also remain relevant.
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11. IANA Considerations
This document makes no requests for IANA action.
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12. Acknowledgements
We wish to thank Adrian Farrel and Lou Berger for their comments and
helps.
This document contains ideas as well as text that have appeared in
existing IETF documents. The authors wish to thank G. Almes, S.
Kalidindi and M. Zekauskas.
We also wish to thank Weisheng Hu, Yaohui Jin and Wei Guo in the
state key laboratory of advanced optical communication systems and
networks for the valuable comments. We also wish to thank the
support from NSFC and 863 program of China.
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13. References
13.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2205] Braden, B., Zhang, L., Berson, S., Herzog, S., and S.
Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
Functional Specification", RFC 2205, September 1997.
[RFC2679] Almes, G., Kalidindi, S., and M. Zekauskas, "A One-way
Delay Metric for IPPM", RFC 2679, September 1999.
[RFC2681] Almes, G., Kalidindi, S., and M. Zekauskas, "A Round-trip
Delay Metric for IPPM", RFC 2681, September 1999.
[RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
Tunnels", RFC 3209, December 2001.
13.2. Informative References
[I-D.shiomoto-ccamp-switch-programming]
Shiomoto, K. and A. Farrel, "Advice on When It is Safe to
Start Sending Data on Label Switched Paths Established
Using RSVP-TE", draft-shiomoto-ccamp-switch-programming-01
(work in progress), October 2009.
[RFC2330] Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
"Framework for IP Performance Metrics", RFC 2330,
May 1998.
[RFC5814] Sun, W. and G. Zhang, "Label Switched Path (LSP) Dynamic
Provisioning Performance Metrics in Generalized MPLS
Networks", RFC 5814, March 2010.
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Authors' Addresses
Weiqiang Sun, Editor
Shanghai Jiao Tong University
800 Dongchuan Road
Shanghai 200240
China
Phone: +86 21 3420 5359
Email: sunwq@mit.edu
Guoying Zhang, Editor
China Academy of Telecommunication Research, MIIT, China.
No.52 Hua Yuan Bei Lu,Haidian District
Beijing 100083
China
Phone: +86 1062300103
EMail: zhangguoying@mail.ritt.com.cn
Jianhua Gao
Huawei Technologies Co., LTD.
China
Phone: +86 755 28973237
Email: gjhhit@huawei.com
Guowu Xie
University of California, Riverside
900 University Ave.
Riverside, CA 92521
USA
Phone: +1 951 237 8825
Email: xieg@cs.ucr.edu
Rajiv Papneja
Isocore
12359 Sunrise Valley Drive, STE 100
Reston, VA 20190
USA
Phone: +1 703 860 9273
Email: rpapneja@isocore.com
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Contributors
Bin Gu
IXIA
Oriental Kenzo Plaza 8M, 48 Dongzhimen Wai Street, Dongcheng District
Beijing 200240
China
Phone: +86 13611590766
Email: BGu@ixiacom.com
Xueqin Wei
Fiberhome Telecommunication Technology Co., Ltd.
Wuhan
China
Phone: +86 13871127882
Email: xqwei@fiberhome.com.cn
Tomohiro Otani
KDDI R&D Laboratories, Inc.
2-1-15 Ohara Kamifukuoka Saitama
356-8502
Japan
Phone: +81-49-278-7357
Email: otani@kddilabs.jp
Ruiquan Jing
China Telecom Beijing Research Institute
118 Xizhimenwai Avenue
Beijing 100035
China
Phone: +86-10-58552000
Email: jingrq@ctbri.com.cn
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