ccamp
Network Working Group                                             W. Sun
Internet-Draft                                                      SJTU
Intended status: Standards Track                                G. Zhang
Expires: September 27, October 12, 2008                                           CATR
                                                                  J. Gao
                                                                  Huawei
                                                                  G. Xie
                                                                    SJTU
                                                              R. Papneja
                                                                 Isocore
                                                                   B. Gu
                                                                    IXIA
                                                                  X. Wei
                                                               Fiberhome
                                                          March 26,

                                                          April 10, 2008

 Label Switched Path (LSP) Dynamical Dynamic Provisioning Performance Metrics in
                       Generalized MPLS Networks
                    draft-ietf-ccamp-lsp-dppm-00.txt
                    draft-ietf-ccamp-lsp-dppm-01.txt

Status of this Memo

   By submitting this Internet-Draft, each author represents that any
   applicable patent or other IPR claims of which he or she is aware
   have been or will be disclosed, and any of which he or she becomes
   aware will be disclosed, in accordance with Section 6 of BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on September 27, October 12, 2008.

Abstract

   Generalized Multi-Protocol Label Switching (GMPLS) is one of the most
   promising candidate technologies for the future data transmission
   network.  The  GMPLS has been developed to control and cooperate operate different
   kinds of network elements, such as conventional routers, switches,
   Dense Wavelength Division Multiplexing (DWDM) systems, Add- Drop
   Multiplexors (ADMs), photonic cross-connects (PXCs), optical
   cross-connects cross-
   connects (OXCs), etc.  Dynamic provisioning ability of these
   physically diverse devices differs from each other drastically.  At
   the same time, the need for dynamically Dynamicly provisioned connections is
   increasing because optical networks are being deployed in metro area.
   areas.  As different applications have varied requirements in the
   provisioning performance of optical networks, it is imperative to
   define standardized metrics and procedures such that the performance
   of networks and application needs can be mapped to each other.

   This document provides a series of performance metrics to evaluate
   the dynamic LSP provisioning performance in GMPLS networks,
   specifically the dynamical Dynamic LSP setup/release performance.  These
   metrics can depict the features of the GMPLS network networks in LSP dynamic
   provisioning.  They can also be used in operational networks for
   carriers to monitor the control plane performance in realtime.

Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  5
   2.  Conventions Used in This Document  . . . . . . . . . . . . . .  6
   3.  Overview of Performance Metrics  . . . . . . . . . . . . . . .  7
   4.  6
   3.  A Singleton Definition for single unidirectional Single Unidirectional LSP Setup
       Delay  . . . . . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.1.  7
     3.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . . .  8
     4.2.  7
     3.2.  Metric Name  . . . . . . . . . . . . . . . . . . . . . . .  8
     4.3.  7
     3.3.  Metric Parameters  . . . . . . . . . . . . . . . . . . . .  8
     4.4.  7
     3.4.  Metric Units . . . . . . . . . . . . . . . . . . . . . . .  9
     4.5.  8
     3.5.  Definition . . . . . . . . . . . . . . . . . . . . . . . .  9
     4.6.  8
     3.6.  Discussion . . . . . . . . . . . . . . . . . . . . . . . .  9
     4.7.  8
     3.7.  Methodologies  . . . . . . . . . . . . . . . . . . . . . . 10
   5.  9
   4.  A Singleton Definition for multiple unidirectional Unidirectional LSP
       Setup Delay  . . . . . . . . . . . . . . . . . . . . . . . . . 11
     5.1. 10
     4.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . . . 11
     5.2. 10
     4.2.  Metric Name  . . . . . . . . . . . . . . . . . . . . . . . 11
     5.3. 10
     4.3.  Metric Parameters  . . . . . . . . . . . . . . . . . . . . 11
     5.4. 10
     4.4.  Metric Units . . . . . . . . . . . . . . . . . . . . . . . 11
     5.5. 10
     4.5.  Definition . . . . . . . . . . . . . . . . . . . . . . . . 11
     5.6. 10
     4.6.  Discussion . . . . . . . . . . . . . . . . . . . . . . . . 12
     5.7. 11
     4.7.  Methodologies  . . . . . . . . . . . . . . . . . . . . . . 13
   6. 12
   5.  A Singleton Definition for single Single Bidirectional LSP Setup
       Delay  . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     6.1. 13
     5.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . . . 14
     6.2. 13
     5.2.  Metric Name  . . . . . . . . . . . . . . . . . . . . . . . 14
     6.3. 13
     5.3.  Metric Parameters  . . . . . . . . . . . . . . . . . . . . 14
     6.4. 13
     5.4.  Metric Units . . . . . . . . . . . . . . . . . . . . . . . 15
     6.5. 14
     5.5.  Definition . . . . . . . . . . . . . . . . . . . . . . . . 15
     6.6. 14
     5.6.  Discussion . . . . . . . . . . . . . . . . . . . . . . . . 15
     6.7. 14
     5.7.  Methodologies  . . . . . . . . . . . . . . . . . . . . . . 16
   7. 15
   6.  A Singleton Definition for multiple Bidirectional LSPs
       Setup Delay  . . . . . . . . . . . . . . . . . . . . . . . . . 17
     7.1. 16
     6.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . . . 17
     7.2. 16
     6.2.  Metric Name  . . . . . . . . . . . . . . . . . . . . . . . 17
     7.3. 16
     6.3.  Metric Parameters  . . . . . . . . . . . . . . . . . . . . 17
     7.4. 16
     6.4.  Metric Units . . . . . . . . . . . . . . . . . . . . . . . 17
     7.5. 16
     6.5.  Definition . . . . . . . . . . . . . . . . . . . . . . . . 17
     7.6. 16
     6.6.  Discussion . . . . . . . . . . . . . . . . . . . . . . . . 18
     7.7. 17
     6.7.  Methodologies  . . . . . . . . . . . . . . . . . . . . . . 19
   8. 18
   7.  A Singleton Definition for LSP Graceful Release Delay  . . . . 20
     8.1. 19
     7.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . . . 20
     8.2. 19
     7.2.  Metric Name  . . . . . . . . . . . . . . . . . . . . . . . 20
     8.3. 19
     7.3.  Metric Parameters  . . . . . . . . . . . . . . . . . . . . 20
     8.4. 19
     7.4.  Metric Units . . . . . . . . . . . . . . . . . . . . . . . 20
     8.5. 19
     7.5.  Definition . . . . . . . . . . . . . . . . . . . . . . . . 20
     8.6. 19
     7.6.  Discussion . . . . . . . . . . . . . . . . . . . . . . . . 21
     8.7. 20
     7.7.  Methodologies  . . . . . . . . . . . . . . . . . . . . . . 22
   9. 21
   8.  Typical Testing cases Cases of single Single Unidirectional LSP Setup
       Delay  . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
     9.1. 23
     8.1.  With no No LSP in the Network . . . . . . . . . . . . . . . . 24
       9.1.1. 23
       8.1.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . 24
       9.1.2. 23
       8.1.2.  Methodologies  . . . . . . . . . . . . . . . . . . . . 24
     9.2. 23
     8.2.  With a Number of LSPs in the Network . . . . . . . . . . . 24
       9.2.1. 23
       8.2.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . 24
       9.2.2. 23
       8.2.2.  Methodologies  . . . . . . . . . . . . . . . . . . . . 24
   10. 23
   9.  Typical Testing cases Cases of multiple Unidirectional LSPs
       Setup Delay  . . . . . . . . . . . . . . . . . . . . . . . . . 26
     10.1. 25
     9.1.  With no No LSP in the Network . . . . . . . . . . . . . . . . 26
       10.1.1. 25
       9.1.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . 26
       10.1.2. 25
       9.1.2.  Methodologies  . . . . . . . . . . . . . . . . . . . . 26
     10.2. 25
     9.2.  With a Number of LSPs in the Network . . . . . . . . . . . 26
       10.2.1. 25
       9.2.1.  Motivation . . . . . . . . . . . . . . . . . . . . . . 26
       10.2.2. 25
       9.2.2.  Methodologies  . . . . . . . . . . . . . . . . . . . . 26
   11. 25
   10. Typical Testing cases Cases of single Single Bidirectional LSP Setup
       Delay  . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
     11.1. 27
     10.1. With no No LSP in the Network . . . . . . . . . . . . . . . . 28
       11.1.1. 27
       10.1.1. Motivation . . . . . . . . . . . . . . . . . . . . . . 28
       11.1.2. 27
       10.1.2. Methodologies  . . . . . . . . . . . . . . . . . . . . 28
     11.2. 27
     10.2. With a Number of LSPs in the Network . . . . . . . . . . . 28
       11.2.1. 27
       10.2.1. Motivation . . . . . . . . . . . . . . . . . . . . . . 28
       11.2.2. 27
       10.2.2. Methodologies  . . . . . . . . . . . . . . . . . . . . 28
   12. 27
   11. Typical Testing cases Cases of multiple Bidirectional LSPs Setup
       Delay  . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
     12.1. 29
     11.1. With no No LSP in the Network . . . . . . . . . . . . . . . . 30
       12.1.1. 29
       11.1.1. Motivation . . . . . . . . . . . . . . . . . . . . . . 30
       12.1.2. 29
       11.1.2. Methodologies  . . . . . . . . . . . . . . . . . . . . 30
     12.2. 29
     11.2. With a Number of LSPs in the Network . . . . . . . . . . . 30
       12.2.1. 29
       11.2.1. Motivation . . . . . . . . . . . . . . . . . . . . . . 30
       12.2.2. 29
       11.2.2. Methodologies  . . . . . . . . . . . . . . . . . . . . 30
   13. 29
   12. Some Statistics Definitions for Metrics to Report  . . . . . . 32
     13.1. 31
     12.1. The Minimum of Metric  . . . . . . . . . . . . . . . . . . 32
     13.2. 31
     12.2. The Median of Metric . . . . . . . . . . . . . . . . . . . 32
     13.3. 31
     12.3. The percentile of Metric . . . . . . . . . . . . . . . . . 32
     13.4. 31
     12.4. The failure probability Failure Probability  . . . . . . . . . . . . . . . . . 32
   14. 31
   13. Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . 32
   14. Security Considerations  . . . . . . . . . . . . . . . . . . . 33
   15. Security IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 34
   16. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 35
   17. References . . . . . . . . . . . . . . . . . . . . . . . . . . 36
     17.1. Normative References . . . . . . . . . . . . . . . . . . . 36
     17.2. Informative References . . . . . . . . . . . . . . . . . . 36
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 37
   Intellectual Property and Copyright Statements . . . . . . . . . . 39

1.  Introduction

   Generalized Multi-Protocol Label Switching (GMPLS) is one of the most
   promising control plane solutions for future transport and service
   network.  GMPLS has been developed to control and cooperate operate different
   kinds of network elements, such as conventional routers, switches,
   Dense Wavelength Division Multiplexing (DWDM) systems, Add-Drop
   Multiplexors (ADMs), photonic cross-connects (PXCs), optical cross-
   connects (OXCs), etc.  Dynamic provisioning ability of these
   physically diverse devices differs from each other drastically.

   The introduction of a control plane into optical circuit switching
   networks automates the provisioning of connections and drastically
   reduces connection provision delay.  As more and more services and
   applications are seeking to use GMPLS controled networks as their
   underlying transport network, and increasingly in a dynamic way, the
   need is growing for measuring and characterizing the performance of
   LSP provisioning in GMPLS networks, such that requirement from
   applications and the provisioning capability of the network can be
   mapped to each other.

   This draft intends to define defines performance metrics and methodologies that can be
   used to depict the dynamic connection provisioning performance of
   GMPLS networks.  The metrics defined in this draft document can in the one
   hand be used to depict the averaged performance of GMPLS
   implementations.  On the other hand, it can also be used in
   operational environments for carriers to monitor the control plane
   operation in realtime.  For example, an new object extensions can be added made to
   the GMPLS
   TE STD MIB [RFC4802] such that the current and past control plane
   performance can be monitored through network management systems.  The
   extension of TE-MIB to support the metrics defined is out the scope
   of this document.

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].

3.  Overview of Performance Metrics

   In this memo, document, to depict the dynamic LSP provisioning performance
   of a GMPLS network, we define 3 5 performance metrics: single/multiple
   unidirectional LSP LSP(s) setup delay, single/multiple bidirectional LSP
   LSP(s) setup delay, and LSP graceful release delay.  The latency of
   the LSP setup/release signal is similar to the Round-trip Delay in IP
   networks.  So we refer 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.

4.

   We further define typical testing cases to obtain samples of the
   defined metrics, namely, when there is no LSP in the network, or
   there are a fixed number of LSPs in the network.

3.  A Singleton Definition for single unidirectional Single Unidirectional LSP Setup Delay

   This part defines a metric for single unidirectional Label Switched
   Path setup delay across a GMPLS network.

4.1.

3.1.  Motivation

   Single unidirectional Label Switched Path setup delay is useful for
   several reasons:

   o  Single LSP setup delay is an important metric that depicts the
      provisioning performance of a GMPLS network.  Longer LSP setup
      delay will incur higher overhead for the requesting application,
      especially when the LSP duration is comparable to the LSP setup
      delay.

   o  The minimum value of this metric provides an indication of the
      delay that will likely be experienced when the LSP traversed the
      shortest route at the lightest load in the control plane.  As the
      delay itself consists of several components, such as link
      propagation delay and nodal processing delay, this metric also
      reflects the status of control plane.  For example, for LSPs
      traversing the same route, longer setup delays may suggest
      congestion in the control channel or high control element load.
      For this reason, this metric is useful for testing and diagnostic
      purposes.

   o  LSP setup delay variance has different impact on to applications.
      Erratic variation in LSP setup delay makes it difficult to support
      applications that has stringent setup delay requirement.

   The measurement of single unidirectional LSP setup delay instead of
   bidirectional LSP setup delay is motivated by the following factors:

   o  Some applications may only use unidirectional LSPs rather than
      bidirectional ones.  For example, content delivery services in
      multicast method (IPTV) only use unidirectional LSPs.

4.2.

3.2.  Metric Name

   single unidirectional LSP setup delay

4.3.

3.3.  Metric Parameters

   o  ID0, the ingress LSR ID

   o  ID1, the egress LSR ID
   o  T, a time

4.4.

3.4.  Metric Units

   The value of single unidirectional LSP setup delay is either a real
   number, or an undefined (informally, infinite) number of
   milliseconds.

4.5.

3.5.  Definition

   The single unidirectional LSP setup delay from the ingress node to
   the egress node [RFC3945] at T is dT means that ingress node sends
   the first bit of a PATH message packet to egress node at wire-time T,
   and that the ingress node received the last bit of responding RESV
   message packet from egress node at wire-time T+dT in the
   unidirectional LSP setup case.

   The single unidirectional LSP setup delay from the ingress node to
   the egress node at T is undefined (informally, infinite), means that
   ingress node sends the first bit of PATH message packet to egress
   node at wire-time T and that ingress node does not receive the
   corresponding RESV message within a reasonable period of time.

4.6.

3.6.  Discussion

   The following issues are likely to come up in practice:

   o  The accuracy of unidirectional LSP setup delay at time T depends
      on the clock resolution in the ingress node; but synchronization
      between the ingress node and egress node is not required since
      unidirectional LSP setup uses two-way signaling.

   o  A given methodology will have to include a way to determine
      whether a latency value is infinite or whether it is merely very
      large.  Simple upper bounds could be used.  But the GMPLS network
      accommodates networks may
      accommodate many kinds of devices.  For example, some photonic
      cross-connects (PXCs) have to move the micro mirrors.  This
      physical motion may take several milliseconds.  But the common
      electronic switches finish the nodal process within several
      microseconds.  So the unidirectional LSP setup delay varies
      drastically from a network to another.  In practice, the upper
      bound should be chose chosen carefully.

   o  If ingress node sends out the PATH message to set up LSP, but
      never receive corresponding RESV message, unidirectional LSP setup
      delay is deemed to be infinite.

   o  If ingress node sends out the PATH message to set up LSP but
      receive PathErr message, unidirectional LSP setup delay is also
      deemed to be infinite.  There are many possible reasons for this
      case.  For example, the PATH message has invalid parameters or the
      network has not enough resource to set up the requested LSP, etc.

4.7.

3.7.  Methodologies

   Generally the methodology would proceed as follows:

   o  Make sure that the network has enough resource to set up the
      requested LSP.

   o  At the ingress node, form the PATH message according to the LSP
      requirements.  A timestamp (T1) may be stored locally in the
      ingress node when the PATH message packet is sent towards the
      egress node.

   o  If the corresponding RESV message arrives within a reasonable
      period of time, take the timestamp (T2) as soon as possible upon
      receipt of the message.  By subtracting the two timestamps, an
      estimate of unidirectional LSP setup delay (T2 -T1) can be
      computed.

   o  If the corresponding RESV message fails to arrive within a
      reasonable period of time, the unidirectional LSP setup delay is
      deemed to be undefined (informally, infinite).  Note that the
      'reasonable' threshold of the unidirectional LSP setup delay is a
      parameter of the methodology.

   o  If the corresponding response message is PathErr, the
      unidirectional LSP setup delay is deemed to be undefined
      (informally, infinite).

5.

4.  A Singleton Definition for multiple unidirectional Unidirectional LSP Setup Delay

   This part defines a metric for multiple unidirectional Label Switched
   Paths setup delay across a GMPLS network.

5.1.

4.1.  Motivation

   multiple unidirectional Label Switched Paths setup delay is useful
   for several reasons:

   o  Upon traffic interruption caused by network failure or network
      upgrade, carriers may require a large number of LSPs be set up
      during a short time period

   o  The time needed to setup a large number of LSPs during a short
      time period can not be deduced by single LSP setup delay

5.2.

4.2.  Metric Name

   multiple unidirectional LSPs setup delay

5.3.

4.3.  Metric Parameters

   o  ID0, the ingress LSR ID

   o  ID1, the egress LSR ID

   o  Lambda, a rate in reciprocal milliseconds

   o  X, the number of LSPs to setup

   o  T, a time

5.4.

4.4.  Metric Units

   The value of multiple unidirectional LSPs setup delay is either a
   real number, or an undefined (informally, infinite) number of
   milliseconds.

5.5.

4.5.  Definition

   Given lambda and X, the multiple unidirectional LSPs setup delay from
   the ingress node to the egress node [RFC3945] at T is dT means:

   o  ingress node sends the first bit of the first PATH message packet
      to egress node at wire-time T
   o  all subsequent (X-1) PATH messages are sent according to the
      specified poisson process with arrival rate lambda

   o  ingress node receives all corresponding RESV message packets from
      egress node, and

   o  ingress node receives the last RESV message packet at wire-time
      T+dT

   The multiple unidirectional LSPs setup delay at T is undefined
   (informally, infinite), means that ingress node sends all the PATH
   messages toward the egress and the first bit of the first PATH
   message packet is sent at wire-time T and that ingress node does not
   receive the one or more of the corresponding RESV messages within a
   reasonable period of time.

5.6.

4.6.  Discussion

   The following issues are likely to come up in practice:

   o  The accuracy of multiple unidirectional LSPs setup delay at time T
      depends on the clock resolution in the ingress node; but
      synchronization between the ingress node and egress node is not
      required since unidirectional LSP setup uses two-way signaling.

   o  A given methodology will have to include a way to determine
      whether a latency value is infinite or whether it is merely very
      large.  Simple upper bounds could be used.  But the GMPLS network
      accommodates networks may
      accommodate many kinds of devices.  For example, some photonic
      cross-connects (PXCs) have to move the micro mirrors.  This
      physical motion may take several milliseconds.  But the common
      electronic switches finish the nodal process within several
      microseconds.  So the multiple unidirectional LSP setup delay
      varies drastically from a network to another.  In practice, the
      upper bound should be chose chosen carefully.

   o  If ingress node sends out the multiple PATH messages to set up the
      LSPs, but never receives one or more of the corresponding RESV
      messages, the unidirectional LSP setup delay is deemed to be
      infinite.

   o  If ingress node sends out the PATH messages to set up the LSPs but
      receives one or more PathErr messages, multiple unidirectional
      LSPs setup delay is also deemed to be infinite.  There are many
      possible reasons for this case.  For example, one of the PATH
      message has invalid parameters or the network has not enough
      resource to set up the requested LSPs, etc.

   o  The arrival rate of the poisson process lambda should be carefully
      chosen such that in the one hand the control plane is not
      overburdened.On the other hand, the arrival rate should also be
      large enough to meet the requirements of applications or services.

5.7.

4.7.  Methodologies

   Generally the methodology would proceed as follows:

   o  Make sure that the network has enough resource to set up the
      requested LSPs.

   o  At the ingress node, form the PATH messages according to the LSPs'
      requirements.

   o  At the ingress node, select the time for each of the PATH messages
      according to the specified poisson process.

   o  At the ingress node, sends out the PATH messages according to the
      selected time.

   o  Store a timestamp (T1) locally in the ingress node when the first
      PATH message packet is sent towards the egress node.

   o  If all of the corresponding RESV messages arrives within a
      reasonable period of time, take the final timestamp (T2) as soon
      as possible upon the receipt of all the messages.  By subtracting
      the two timestamps, an estimate of multiple unidirectional LSPs
      setup delay (T2 -T1) can be computed.

   o  If one or more of the corresponding RESV messages fails to arrive
      within a reasonable period of time, the multiple unidirectional
      LSPs setup delay is deemed to be undefined (informally, infinite).
      Note that the 'reasonable' threshold is a parameter of the
      methodology.

   o  If one of the corresponding response message is PathErr, the
      multiple unidirectional LSPs setup delay is deemed to be undefined
      (informally, infinite).

6.

5.  A Singleton Definition for single Single Bidirectional LSP Setup Delay

   GMPLS allows establishment of bi-directional symmetric LSPs (not of
   asymmetric LSPs).  This part defines a metric for single
   bidirectional LSP setup delay across a GMPLS network.

6.1.

5.1.  Motivation

   Single bidirectional Label Switched Path setup delay is useful for
   several reasons:

   o  LSP setup delay is an important metric that depicts the
      provisioning performance of a GMPLS network.  Longer LSP setup
      delay will incur higher overhead for the requesting application,
      especially when the LSP duration is comparable to the LSP setup
      delay.  Thus, measuring the setup delay is important for
      applications scheduling.

   o  The minimum value of this metric provides an indication of the
      delay that will likely be experienced when the LSP traversed the
      shortest route at the lightest load in the control plane.  As the
      delay itself consists of several components, such as link
      propagation delay and nodal processing delay, this metric also
      reflects the status of control plane.  For example, for LSPs
      traversing the same route, longer setup delays may suggest
      congestion in the control channel or high control element load.
      For this reason, this metric is useful for testing and diagnostic
      purposes.

   o  LSP setup delay variance has different impact on to applications.
      Erratic variation in LSP setup delay makes it difficult to support
      applications that has stringent setup delay requirement.

   The measurement of single bidirectional LSP setup delay instead of
   unidirectional LSP setup delay is motivated by the following factors:

   o  Bidirectional LSPs are seen as a requirement for many GMPLS
      networks.  Its provisioning performance is important to
      applications that generates bi-directional traffic.

6.2.

5.2.  Metric Name

   Single bidirectional LSP setup delay

6.3.

5.3.  Metric Parameters
   o  ID0, the ingress LSR ID

   o  ID1, the egress LSR ID

   o  T, a time

6.4.

5.4.  Metric Units

   The value of single bidirectional LSP setup delay is either a real
   number, or an undefined (informally, infinite) number of
   milliseconds.

6.5.

5.5.  Definition

   For a real number dT, the single bidirectional LSP setup delay from
   ingress node to egress node at T is dT, means that ingress node sends
   out the first bit of a PATH message including an Upstream Label
   [RFC3473] heading for egress node at wire-time T, egress node
   receives that packet, then immediately sends a RESV message packet
   back to ingress node, and that ingress node receives the last bit of
   that packet at wire-time T+dT.

   The single bidirectional LSP setup delay from ingress node to egress
   node at T is undefined (informally, infinite), means that ingress
   node sends the first bit of PATH message to egress node at wire-time
   T and that ingress node does not receive that response packet.

6.6.

5.6.  Discussion

   The following issues are likely to come up in practice:

   o  The accuracy of single bidirectional LSP setup delay depends on
      the clock resolution in the ingress node; but synchronization
      between the ingress node and egress node is not required since
      single bidirectional LSP setup uses two-way signaling.

   o  A given methodology will have to include a way to determine
      whether a latency value is infinite or whether it is merely very
      large.  Simple upper bounds could be used.  But the GMPLS network
      accommodates networks may
      accommodate many kinds of devices.  For example, some photonic
      cross-connects (PXCs) have to move the micro mirrors.  This
      physical motion may take several milliseconds.  But the common
      electronic switches finish the nodal process within several
      microseconds.  So the bidirectional LSP setup delay varies
      drastically from a network to another.  In the process of
      bidirectional LSP setup, if the downstream node overrides the
      label suggested by the upstream node, the setup delay will also
      increase obviously.  Thus, in practice, the upper bound should be
      chosen carefully.

   o  If the ingress node sends out the PATH message to set up the LSP,
      but never receives the corresponding RESV message, single
      bidirectional LSP setup delay is deemed to be infinite.

   o  If the ingress node sends out the PATH message to set up the LSP,
      but receives PathErr message, single bidirectional LSP setup delay
      is also deemed to be infinite.  There are many possible reasons
      for this case.  For example, the PATH message has invalid
      parameters or the network has not enough resource to set up the
      requested LSP.

6.7.

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  At the ingress node, form the PATH message (including the Upstream
      Label or suggested label) according to the LSP requirements.  A
      timestamp (T1) may be stored locally in the ingress node when the
      PATH message packet is sent towards the egress node.

   o  If the corresponding RESV message arrives within a reasonable
      period of time, take the final timestamp (T2) as soon as possible
      upon the receipt of the message.  By subtracting the two
      timestamps, an estimate of bidirectional LSP setup delay (T2 -T1)
      can be computed.

   o  If the corresponding RESV message fails to arrive within a
      reasonable period of time, the single bidirectional LSP setup
      delay is deemed to be undefined (informally, infinite).  Note that
      the 'reasonable' threshold is a parameter of the methodology.

   o  If the corresponding response message is PathErr, the single
      bidirectional LSP setup delay is deemed to be undefined
      (informally, infinite).

7.

6.  A Singleton Definition for multiple Bidirectional LSPs Setup Delay

   This part defines a metric for multiple bidirectional LSPs setup
   delay across a GMPLS network.

7.1.

6.1.  Motivation

   multiple Bidirectional LSPs setup delay is useful for several
   reasons:

   o  Upon traffic interruption caused by network failure or network
      upgrade, carriers may require a large number of LSPs be set up
      during a short time period

   o  The time needed to setup a large number of LSPs during a short
      time period can not be deduced by single LSP setup delay

7.2.

6.2.  Metric Name

   Multiple bidirectional LSPs setup delay

7.3.

6.3.  Metric Parameters

   o  ID0, the ingress LSR ID

   o  ID1, the egress LSR ID

   o  Lambda, a rate in reciprocal milliseconds

   o  X, the number of LSPs to setup

   o  T, a time

7.4.

6.4.  Metric Units

   The value of multiple bidirectional LSPs setup delay is either a real
   number, or an undefined (informally, infinite) number of
   milliseconds.

7.5.

6.5.  Definition

   Given lambda and X, for a real number dT, the multiple bidirectional
   LSPs setup delay from ingress node to egress node at T is dT, means
   that:

   o  ingress node sends the first bit of the first PATH message heading
      for egress node at wire-time T
   o  all subsequent (X-1) PATH messages are sent according to the
      specified poisson process with arrival rate lambda

   o  ingress node receives all corresponding RESV message packets from
      egress node, and

   o  ingress node receives the last RESV message packets at wire-time
      T+dT

   The multiple bidirectional LSPs setup delay from ingress node to
   egress node at T is undefined (informally, infinite), means that
   ingress node sends all the PATH messages to egress node and that the
   ingress node dose not receive one or more of the response messages.

7.6.

6.6.  Discussion

   The following issues are likely to come up in practice:

   o  The accuracy of multiple bidirectional LSPs setup delay depends on
      the clock resolution in the ingress node; but synchronization
      between the ingress node and egress node is not required since
      bidirectional LSP setup uses two-way signaling.

   o  A given methodology will have to include a way to determine
      whether a latency value is infinite or whether it is merely very
      large.  Simple upper bounds could be used.  But the GMPLS network
      accommodates networks may
      accommodate many kinds of devices.  For example, some photonic
      cross-connects (PXCs) have to move the micro mirrors.  This
      physical motion may take several milliseconds.  But the common
      electronic switches finish the nodal process within several
      microseconds.  So the bidirectional LSP setup delay varies
      drastically from a network to another.  In the process of
      bidirectional LSP setup, if the downstream node overrides the
      label suggested by the upstream node, the setup delay will also
      increase obviously.  Thus, in practice, the upper bound should be
      chosen carefully.

   o  If the ingress node sends out the PATH messages to set up the
      LSPs, but never receive all the corresponding RESV messages, the
      multiple bidirectional LSPs setup delay is deemed to be infinite.

   o  If the ingress node sends out the PATH messages to set up the
      LSPs, but receive one or more responding PathErr messages,the
      multiple bidirectional LSPs setup delay is also deemed to be
      infinite.  There are many possible reasons for this case.  For
      example, one or more of the PATH messages have invalid parameters
      or the network has not enough resource to set up the requested
      LSPs.

   o  The arrival rate of the poisson process lambda should be carefully
      chosen such that in the one hand the control plane is not
      overburdened.On the other hand, the arrival rate should also be
      large enough to meet the requirements of applications or services.

7.7.

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  At the ingress node, form the PATH messages (including the
      Upstream Label or suggested label) according to the LSPs'
      requirements.

   o  At the ingress node, select the time for each of the PATH messages
      according to the specified poisson process.

   o  At the ingress node, sends out the PATH messages according to the
      selected time.

   o  Store a timestamp (T1) locally in the ingress node when the first
      PATH message packet is sent towards the egress node.

   o  If all of the corresponding RESV messages arrives within a
      reasonable period of time, take the final timestamp (T2) as soon
      as possible upon the receipt of all the messages.  By subtracting
      the two timestamps, an estimate of multiple bidirectional LSPs
      setup delay (T2 -T1) can be computed.

   o  If one or more of the corresponding RESV messages fails to arrive
      within a reasonable period of time, the multiple bidirectional
      LSPs setup delay is deemed to be undefined (informally, infinite).
      Note that the 'reasonable' threshold is a parameter of the
      methodology.

   o  If one or more of the corresponding response messages is PathErr,
      the multiple bidirectional LSPs setup delay is deemed to be
      undefined (informally, infinite).

8.

7.  A Singleton Definition for LSP Graceful Release Delay

   There are two different kinds of LSP release mechanisms in the GMPLS
   network:
   networks: graceful release and forceful release.  Memo in current
   version has not taken forceful LSP release procedure into account.

8.1.

7.1.  Motivation

   LSP graceful release delay is useful for several reasons:

   o  The LSP graceful release delay is part of the total cost of
      dynamic LSP provisioning.  For some short duration applications,
      the LSP tear down time can not be ignored

   o  The LSP graceful release procedure is more prefered in a GMPLS
      controled network, particularly the optical networks.  Since it
      doesn't trigger restoration/protection, it is "alarm-free
      connection deletion" in [RFC4208].

8.2.

7.2.  Metric Name

   LSP graceful release delay

8.3.

7.3.  Metric Parameters

   o  ID0, the ingress LSR ID

   o  ID1, the egress LSR ID

   o  T, a time

8.4.

7.4.  Metric Units

   The value of LSP graceful release delay is either a real number, or
   an undefined (informally, infinite) number of milliseconds.

8.5.

7.5.  Definition

   There are two different LSP graceful release procedures, one is
   initiated by the ingress node, and another is initiated by egress
   node.  The two procedures are depicted in the [RFC3473].  We define
   the graceful LSP release delay for these two procedures separately.

   For a real number dT, the LSP graceful release delay from ingress
   node to egress node at T is dT, means that ingress node sends the
   first bit of a PATH message including Admin Status Object with
   setting the Reflect (R) and Delete (D) bits to egress node at wire-
   time T, that egress node receives that packet, then immediately sends
   a RESV message including Admin Status Object with the Delete (D) bit
   set back to ingress node.  The ingress node sends out PathTear
   downstream to remove the LSP, and egress node receives the last bit
   of PathTear packet at wire-time T+dT.

   Also as an option, upon receipt of the PATH message including Admin
   Status Object with setting the Reflect (R) and Delete (D) bits, the
   egress node may respond with PathErr message with the
   Path_State_Removed flag set.

   The LSP graceful release delay from ingress node to egress node at T
   is undefined (informally, infinite), means that ingress node sends
   the first bit of PATH message to egress node at wire-time T and that
   (either egress node does not receive the PATH packet, egress node
   does not send corresponding RESV message packet in response, ingress
   node does not receive that RESV packet, or) the egress does not
   receive the PathTear.

   The LSP graceful release delay from egress node to ingress node at T
   is dT, means that egress node sends the first bit of a RESV message
   including Admin Status Object with setting the Reflect (R) and Delete
   (D) bits to ingress node at wire-time T. The ingress node sends out
   PathTear downstream to remove the LSP, and egress node receives the
   last bit of PathTear packet at wire-time T+dT.

   The LSP graceful release delay from egress node to ingress node at T
   is undefined (informally, infinite), means that egress node sends the
   first bit of RESV message including Admin Status Object with setting
   the Reflect (R) and Delete (D) bits to ingress node at wire-time T
   and that (either ingress node does not receive the RESV packet,
   ingress node does not send PathTear message packet in response or)
   the egress does not receive the PathTear.

8.6.

7.6.  Discussion

   The following issues are likely to come up in practice:

   o  In the first (second) circumstance, the accuracy of LSP graceful
      release delay at time T depends on the clock resolution in the
      ingress (egress) node.  In the first circumstance, synchronization
      between the ingress node and egress node is required; but not in
      the second circumstance;

   o  A given methodology has to include a way to determine whether a
      latency value is infinite or whether it is merely very large.
      Simple upper bounds could be used.  But the upper bound should be
      chosen carefully in practice;
   o  In the first circumstance, if ingress node sends out PATH message
      including Admin Status Object with the Reflect (R) and Delete (D)
      bits set to initiate LSP graceful release, but never receive
      corresponding RESV message, LSP graceful release delay is deemed
      to be infinite.  In the second circumstance, if egress node sends
      out RESV message including Admin Status Object with the Reflect
      (R) and Delete (D) bits set to initiate LSP graceful release, but
      never receive corresponding PathTear message, LSP graceful release
      delay is deemed to be infinite;

8.7.

7.7.  Methodologies

   In the first circumstance, the methodology may proceed as follows:

   o  Make sure the LSP to be deleted is set up;

   o  At the egress node, form the PATH message including Admin Status
      Object with the Reflect (R) and Delete (D) bits set.  A timestamp
      (T1) may be stored locally in the ingress node when the PATH
      message packet is sent towards the egress node;

   o  Upon receiving the PATH message including Admin Status Object with
      the Reflect (R) and Delete (D) bits set, the egress node sends a
      RESV message including Admin Status Object with the Delete (D) and
      Reflect (R) bits set.  Or, alternatively, the egress node sends a
      PathErr message with the Path_State_Removed flag set upstream;

   o  When the ingress node receive the RESV message or the PathErr
      message, it sends a PathTear message to remove the LSP;

   o  Egress node takes a timestamp (T2) once it receives the last bit
      of the PathTear message.  The LSP graceful release delay is then
      (T2-T1).

   In the second circumstance, the methodology would proceed as follows:

   o  Make sure the LSP to be deleted is set up;

   o  On the egress node, form the RESV message including Admin Status
      Object with the Reflect (R) and Delete (D) bits set.  A timestamp
      may be stored locally in the egress node when the RESV message
      packet is sent towards the ingress node;

   o  Upon receiving the Admin Status Object with the Reflect (R) and
      Delete (D) bits set in the RESV message, the ingress node sends a
      PathTear message downstream to remove the LSP;
   o  Egress node takes a timestamp (T2) once it receives the last bit
      of the PathTear message.  The LSP graceful release delay is then
      (T2-T1).

9.

8.  Typical Testing cases Cases of single Single Unidirectional LSP Setup Delay

   Now we define typical test cases of getting unidirectional LSP setup
   delay.

9.1.

8.1.  With no No LSP in the Network

9.1.1.

8.1.1.  Motivation

   Single unidirectional LSP setup delay with no LSP in the network is
   important because this reflects the inherent delay of an RSVP-TE
   implementation.  The minimum value provides an indication of the
   delay that will likely be experienced when an LSP traverses the
   shortest route with the lightest load in the control plane.

9.1.2.

8.1.2.  Methodologies

   Make sure that there is no or very few LSPs in the network.  The
   methodology would proceed as follows:

   o  Set up the LSP using the methodology for the singleton single
      unidirectional LSP setup delay, and obtain the value of
      unidirectional LSP setup delay

   o  Release the LSP

   o  Repeat this process if multiple samples are needed

   Note that: in case multiple samples are to be obtained, the interval
   between each process should be large enough to guarantee the network
   has already reached a stable state.

9.2.

8.2.  With a Number of LSPs in the Network

9.2.1.

8.2.1.  Motivation

   Single unidirectional LSP setup delay with a number of LSPs in the
   network is important because it reflects the performance of an
   operational network with considrable load.  This delay can vary
   significantly as the number of existing LSPs vary.  It can be used as
   a scalability metric of an RSVP-TE implementation.

9.2.2.

8.2.2.  Methodologies

   Setup the required number of LSPs, and wait until the network reaches
   a stable state, then proceed as follows:

   o  Set up the LSP using the methodology for the singleton single
      unidirectional LSP setup delay, and obtain the value of
      unidirectional LSP setup delay

   o  Release the LSP

   o  Repeat this process if multiple samples are needed

   Note that: in case multiple samples are to be obtained, the interval
   between each process should be large enough to guarantee the network
   has already reached a stable state.

10.

9.  Typical Testing cases Cases of multiple Unidirectional LSPs Setup Delay

   Now we define typical test cases of getting multiple unidirectional
   LSPs setup delay.

10.1.

9.1.  With no No LSP in the Network

10.1.1.

9.1.1.  Motivation

   multiple unidirectional LSP setup delay with no LSP in the network is
   important because this reflects the inherent delay of an RSVP-TE
   implementation.  The minimum value provides an indication of the
   delay that will likely be experienced when a number of LSPs are setup
   with the lightest load in the control plane.

10.1.2.

9.1.2.  Methodologies

   Make sure that there is no or very few LSPs in the network.  The
   methodology would proceed as follows:

   o  Set up the LSPs using the methodology for the singleton multiple
      unidirectional LSP setup delay, and obtain the value of multiple
      unidirectional LSP setup delay

   o  Release the LSPs

   o  Repeat this process if multiple samples are needed

   Note that: in case multiple samples are to be obtained, the interval
   between each process should be large enough to guarantee the network
   has already reached a stable state.

10.2.

9.2.  With a Number of LSPs in the Network

10.2.1.

9.2.1.  Motivation

   multiple unidirectional LSP setup delay with a number of LSPs in the
   network is important because it reflects the performance of an
   operational network with considrable load.  This delay can vary
   significantly as the number of existing LSPs vary.  It can be used as
   a scalability metric of an RSVP-TE implementation.

10.2.2.

9.2.2.  Methodologies

   Setup the required number of LSPs, and wait until the network reaches
   a stable state, then proceed as follows:

   o  Set up the LSPs using the methodology for the singleton multiple
      unidirectional LSP setup delay, and obtain the value of multiple
      unidirectional LSP setup delay

   o  Release the LSPs

   o  Repeat this process if multiple samples are needed

   Note that: in case multiple samples are to be obtained, the interval
   between each process should be large enough to guarantee the network
   has already reached a stable state.

11.

10.  Typical Testing cases Cases of single Single Bidirectional LSP Setup Delay

   Now we define typical test cases of getting single bidirectional LSP
   setup delay.

11.1.

10.1.  With no No LSP in the Network

11.1.1.

10.1.1.  Motivation

   Single unidirectional LSP setup delay with no LSP in the network is
   important because this reflects the inherent delay of an RSVP-TE
   implementation.  The minimum value provides an indication of the
   delay that will likely be experienced when an LSP traverses the
   shortest route with the lightest load in the control plane.

11.1.2.

10.1.2.  Methodologies

   Make sure that there is no or very few LSPs in the network.  The
   methodology would proceed as follows:

   o  Set up the LSP using the methodology for the singleton
      bidirectional LSP setup delay, and obtain the value of
      unidirectional LSP setup delay

   o  Release the LSP

   o  Repeat this process if multiple samples are needed

   Note that: in case multiple samples are to be obtained, the interval
   between each process should be large enough to guarantee the network
   has already reached a stable state.

11.2.

10.2.  With a Number of LSPs in the Network

11.2.1.

10.2.1.  Motivation

   Single bidirectional LSP setup delay with a number of LSPs in the
   network is important because it reflects the performance of an
   operational network with considrable load.  This delay can vary
   significantly as the number of existing LSPs vary.  It can be used as
   a scalability metric of an RSVP-TE implementation.

11.2.2.

10.2.2.  Methodologies

   Setup the required number of LSPs, and wait until the network reaches
   a stable state, then proceed as follows:

   o  Set up the LSP using the methodology for the singleton
      bidirectional bidirectional LSP setup delay, and obtain the value
      of bidirectional LSP setup delay

   o  Release the LSP

   o  Repeat this process if multiple samples are needed

   Note that: in case multiple samples are to be obtained, the interval
   between each process should be large enough to guarantee the network
   has already reached a stable state.

12.

11.  Typical Testing cases Cases of multiple Bidirectional LSPs Setup Delay

   Now we define typical test cases of getting multiple bidirectional
   LSPs setup delay.

12.1.

11.1.  With no No LSP in the Network

12.1.1.

11.1.1.  Motivation

   multiple bidirectional LSP setup delay with no LSP in the network is
   important because this reflects the inherent delay of an RSVP-TE
   implementation.  The minimum value provides an indication of the
   delay that will likely be experienced when a number of LSPs are setup
   with the lightest load in the control plane.

12.1.2.

11.1.2.  Methodologies

   Make sure that there is no or very few LSPs in the network.  The
   methodology would proceed as follows:

   o  Set up the LSPs using the methodology for the singleton multiple
      multiple bidirectional LSP setup delay, and obtain the value of
      multiple bidirectional LSP setup delay

   o  Release the LSPs

   o  Repeat this process if multiple samples are needed

   Note that: in case multiple samples are to be obtained, the interval
   between each process should be large enough to guarantee the network
   has already reached a stable state.

12.2.

11.2.  With a Number of LSPs in the Network

12.2.1.

11.2.1.  Motivation

   multiple bidirectional LSPs setup delay with a number of LSPs in the
   network is important because it reflects the performance of an
   operational network with considrable load.  This delay can vary
   significantly as the number of existing LSPs vary.  It can be used as
   a scalability metric of an RSVP-TE implementation.

12.2.2.

11.2.2.  Methodologies

   Setup the required number of LSPs, and wait until the network reaches
   a stable state, then proceed as follows:

   o  Set up the LSPs using the methodology for the singleton multiple
      bidirectional LSPs setup delay, and obtain the value of multiple
      bidirectional LSPs setup delay

   o  Release the LSPs

   o  Repeat this process if multiple samples are needed

   Note that: in case multiple samples are to be obtained, the interval
   between each process should be large enough to guarantee the network
   has already reached a stable state.

13.

12.  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 (informally,
   infinite) number of milliseconds.  In the following discussion, we
   only consider the finite values.

13.1.

12.1.  The Minimum of Metric

   The minimum of metric is the minimum of all the dT values in the
   sample.  In computing this, undefined values are treated as
   infinitely large.  Note that this means that the minimum could thus
   be undefined (informally, infinite) if all the dT values are
   undefined.  In addition, the metric minimum is undefined if the
   sample is empty.

13.2.

12.2.  The Median of Metric

   Metric median is the median of the dT values in the given sample.  In
   computing the median, the undefined values are not counted in.

13.3.

12.3.  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
   unidirectional LSP setup delay 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).

13.4.

12.4.  The failure probability Failure Probability

   In the process of LSP setup/release, it may fail for some reason.
   The failure probability is the ratio of the failure times to the
   total times.

14.

13.  Discussion

   It is worthwhile to point out that:

   o  The unidirectional/bidirectional LSP setup delay is one ingress-
      egress round trip time plus processing time.  But in the draft, this
      document, unidirectional/bidirectional LSP setup delay has not
      taken the processing time in the end nodes (ingress or/and egress)
      into account.  The timestamp T2 is taken after the endpoint node
      receives it.  Actually, the last node has to take some time to
      process local procedure.  Similarly, in the LSP graceful release
      delay, the memo has not considered the processing time in the
      endpoint node.

   o  All these metrics are defined from the point of control plane's
      view.  In fact, the control plane and data plane are not always
      synchronized.  In some cases, the LSPs have been set up in the
      control plane.  But the data can not be forwarded immediately.  The
      unidirectional/bidirectional LSP setup delay in the data plane is
      longer than in the control plane.

15.

14.  Security Considerations

   Samples of the metrics can be obtained in either active or passive
   manners.

   In the active manner, ingress nodes inject probing messages into the
   control plane.  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.

   When samples of the metrics are collected in a passive manner, e.g.,
   by monitoring the operations on real-life LSPs, the implementation of
   the monitoring and reporting mechanism must be careful so that they
   will not be used to attack the control plane.

   Besides, the security considerations pertaining to the original RSVP
   protocol [RFC2205] and its TE extensions [RFC3209] also remain
   relevant.

15.  IANA Considerations

   This document makes no requests for IANA action.

16.  Acknowledgements

   We wish to thank Dan Li, Fang Liu (Christine), Zafar Ali, Monique
   Morrow, Al Morton, Adrian Farrel, Deborah Brungard, Thomas D. Nadeau
   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.

17.  References

17.1.  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.

   [RFC2330]  Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
              "Framework for IP Performance Metrics", RFC 2330,
              May 1998.

   [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.

   [RFC3473]  Berger, L., "Generalized Multi-Protocol Label Switching
              (GMPLS) Signaling Resource ReserVation Protocol-Traffic
              Engineering (RSVP-TE) Extensions", RFC 3473, January 2003.

   [RFC3945]  Mannie, E., "Generalized Multi-Protocol Label Switching
              (GMPLS) Architecture", RFC 3945, October 2004.

   [RFC4208]  Swallow, G., Drake, J., Ishimatsu, H., and Y. Rekhter,
              "Generalized Multiprotocol Label Switching (GMPLS) User-
              Network Interface (UNI): Resource ReserVation Protocol-
              Traffic Engineering (RSVP-TE) Support for the Overlay
              Model", RFC 4208, October 2005.

   [RFC4802]  Nadeau, T. and A. Farrel, "Generalized Multiprotocol Label
              Switching (GMPLS) Traffic Engineering Management
              Information Base", RFC 4802, February 2007.

17.2.  Informative References

   [RFC2330]  Paxson, V., Almes, G., Mahdavi, J., and M. Mathis,
              "Framework for IP Performance Metrics", RFC 2330,
              May 1998.

Authors' Addresses

   Weiqiang Sun
   Shanghai Jiao Tong University
   800 Dongchuan Road
   Shanghai  200240
   CN

   Phone: +86 21 3420 5359
   Email: sunwq@sjtu.edu.cn

   Guoying Zhang
   China Academy of Telecommunication Research,MII.
   Beijing  200240
   CN

   Phone: +86 1068094272
   Email: zhangguoying@mail.ritt.com.cn

   Jianhua Gao
   Huawei Technologies Co., LTD.
   CN

   Phone: +86 755 28973237
   Email: gjhhit@huawei.com

   Guowu Xie
   Shanghai Jiao Tong University
   800 Dongchuan Road
   Shanghai  200240
   CN

   Phone: +86 21 3420 4596
   Email: blithe@sjtu.edu.cn

   Rajiv Papneja
   Isocore
   12359 Sunrise Valley Drive, STE 100
   Reston, VA  20190
   USA

   Phone: +1 703 860 9273
   Email: rpapneja@isocore.com
   Bin Gu
   IXIA
   Oriental Kenzo Plaza 8M,48 Dongzhimen Wai Street,Dongcheng District
   Beijing  200240
   CN

   Phone: +86 13611590766
   Email: BGu@ixiacom.com

   Xueqing Wei
   Fiberhome Telecommunicaiton Technology Co.,Ltd.
   Wuhan
   CN

   Phone: +86 13871127882
   Email: xqwei@fiberhome.com.cn

Full Copyright Statement

   Copyright (C) The IETF Trust (2008).

   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.