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Versions: (draft-gray-mpls-tp-nm-req) 00 01 02 03 04 05 06 RFC 5951

 Network Working Group                                  Hing-Kam Lam
 Internet Draft                                       Alcatel-Lucent
 Expires: March, 2010                                Scott Mansfield
 Intended Status: Standards Track                          Eric Gray
                                                            Ericsson
                                                    October 21, 2009
 
                 MPLS TP Network Management Requirements
                     draft-ietf-mpls-tp-nm-req-06.txt
 
 
 Status of this Memo
 
    This Internet-Draft is submitted to IETF in full conformance with
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    This Internet-Draft will expire on April 21, 2010.
 
 Abstract
 
    This document specifies the requirements for the management of
    equipment used in networks supporting an MPLS Transport Profile
    (MPLS-TP). The requirements are defined for specification of
    network management aspects of protocol mechanisms and procedures
    that constitute the building blocks out of which the MPLS
    transport profile is constructed.  That is, these requirements
    indicate what management capabilities need to be available in
    MPLS for use in managing the MPLS-TP. This document is intended
    to identify essential network management capabilities, not to
    specify what functions any particular MPLS implementation
    supports.
 
 
 
 
 
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 Table of Contents
 
 
    1. Introduction................................................3
       1.1. Terminology............................................4
    2. Management Interface Requirements...........................6
    3. Management Communication Channel (MCC) Requirements.........6
    4. Management Communication Network (MCN) Requirements.........7
    5. Fault Management Requirements...............................8
       5.1. Supervision Function...................................8
       5.2. Validation Function....................................9
       5.3. Alarm Handling Function...............................10
          5.3.1. Alarm Severity Assignment........................10
          5.3.2. Alarm Suppression................................11
          5.3.3. Alarm Reporting..................................11
          5.3.4. Alarm Reporting Control..........................11
    6. Configuration Management Requirements......................12
       6.1. System Configuration..................................12
       6.2. Control Plane Configuration...........................12
       6.3. Path Configuration....................................12
       6.4. Protection Configuration..............................13
       6.5. OAM Configuration.....................................14
    7. Performance Management Requirements........................14
       7.1. Path Characterization Performance Metrics.............15
       7.2. Performance Measurement Instrumentation...............16
          7.2.1. Measurement Frequency............................16
          7.2.2. Measurement Scope................................16
    8. Security Management Requirements...........................17
       8.1. Management Communication Channel Security.............17
       8.2. Signaling Communication Channel Security..............17
       8.3. Distributed Denial of Service.........................18
    9. Security Considerations....................................18
    10. IANA Considerations.......................................19
    11. Acknowledgments...........................................19
    12. References................................................19
       12.1. Normative References.................................19
       12.2. Informative References...............................20
    Author's Addresses............................................21
    Copyright Statement...........................................22
    Acknowledgment................................................22
    Appendix A - Communication Channel (CCh) Examples.............23
 
 
 
 
 
 
 
 
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 1. Introduction
 
    This document specifies the requirements for the management of
    equipment used in networks supporting an MPLS Transport Profile
    (MPLS-TP). The requirements are defined for specification of
    network management aspects of protocol mechanisms and procedures
    that constitute the building blocks out of which the MPLS
    transport profile is constructed.  That is, these requirements
    indicate what management capabilities need to be available in
    MPLS for use in managing the MPLS-TP. This document is intended
    to identify essential network management capabilities, not to
    specify what functions any particular MPLS implementation
    supports.
 
    This document also leverages management requirements specified in
    ITU-T G.7710/Y.1701 [1] and RFC 4377 [2], and attempts to comply
    with best common practice as defined in [15].
 
    ITU-T G.7710/Y.1701 defines generic management requirements for
    transport networks. RFC 4377 specifies the OAM requirements,
    including OAM-related network management requirements, for MPLS
    networks.
 
    This document is a product of a joint ITU-T and IETF effort to
    include an MPLS Transport Profile (MPLS-TP) within the IETF MPLS
    and PWE3 architectures to support capabilities and functionality
    of a transport network as defined by ITU-T.
 
    The requirements in this document derive from two sources:
 
       1) MPLS and PWE3 architectures as defined by IETF, and
 
       2) packet transport networks as defined by ITU-T.
 
    Requirements for management of equipment in MPLS-TP networks are
    defined herein.  Related functions of MPLS and PWE3 are defined
    elsewhere (and are out of scope in this document).
 
    This document expands on the requirements in [1] and [2] to cover
    fault, configuration, performance, and security management for
    MPLS-TP networks, and the requirements for object and information
    models needed to manage MPLS-TP Networks and Network Elements.
 
    In writing this document, the authors assume the reader is
    familiar with references [8] and [9].
 
 
 
 
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  1.1. Terminology
 
    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
    RFC 2119 [5]. Although this document is not a protocol
    specification, the use of this language clarifies the
    instructions to protocol designers producing solutions that
    satisfy the requirements set out in this document.
 
    Anomaly: The smallest discrepancy which can be observed between
    actual and desired characteristics of an item. The occurrence of
    a single anomaly does not constitute an interruption in ability
    to perform a required function. Anomalies are used as the input
    for the Performance Monitoring (PM) process and for detection of
    defects (from [21], 3.7).
 
    Communication Channel (CCh): A logical channel between network
    elements (NEs) that can be used - e.g. - for management or
    control plane applications. The physical channel supporting the
    CCh is technology specific.  See Appendix A.
 
    Data Communication Network (DCN): A network that supports Layer 1
    (physical layer), Layer 2 (data-link layer), and Layer 3 (network
    layer) functionality for distributed management communications
    related to the management plane, for distributed signaling
    communications related to the control plane, and other operations
    communications (e.g., order-wire/voice communications, software
    downloads, etc.).
 
    Defect: The density of anomalies has reached a level where the
    ability to perform a required function has been interrupted.
    Defects are used as input for performance monitoring, the control
    of consequent actions, and the determination of fault cause (from
    [21], 3.24).
 
    Failure: The fault cause persisted long enough to consider the
    ability of an item to perform a required function to be
    terminated. The item may be considered as failed; a fault has now
    been detected (from [21], 3.25).
 
    Fault: A fault is the inability of a function to perform a
    required action. This does not include an inability due to
    preventive maintenance, lack of external resources, or planned
    actions (from [21], 3.26).
 
 
 
 
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    Fault Cause: A single disturbance or fault may lead to the
    detection of multiple defects. A fault cause is the result of a
    correlation process which is intended to identify the defect that
    is representative of the disturbance or fault that is causing the
    problem (from [21], 3.27).
 
    Fault Cause Indication (FCI): An indication of a fault cause.
 
    Management Communication Channel (MCC): A CCh dedicated for
    management plane communications.
 
    Management Communication Network (MCN): A DCN supporting
    management plane communication is referred to as a Management
    Communication Network (MCN).
 
    MPLS-TP NE: A network element (NE) that supports the functions of
    MPLS necessary to participate in an MPLS-TP based transport
    service. See [7] for further information on functionality
    required to support MPLS-TP.
 
    MPLS-TP network: a network in which MPLS-TP NEs are deployed.
 
    OAM, On-Demand and Proactive: One feature of OAM that is largely
    a management issue is control of OAM; on-demand and proactive are
    modes of OAM mechanism operation defined - for example - in
    Y.1731 ([22] - 3.45 and 3.44 respectively) as:
 
       . On-demand OAM - OAM actions which are initiated via manual
          intervention for a limited time to carry out diagnostics.
          On-demand OAM can result in singular or periodic OAM actions
          during the diagnostic time interval.
 
       . Proactive OAM - OAM actions which are carried on
          continuously to permit timely reporting of fault and/or
          performance status.
 
    (Note that it is possible for specific OAM mechanisms to only
    have a sensible use in either on-demand or proactive mode.)
 
    Operations System (OS): A system that performs the functions that
    support processing of information related to operations,
    administration, maintenance, and provisioning (OAM&P) for the
    networks, including surveillance and testing functions to support
    customer access maintenance.
 
 
 
 
 
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    Signaling Communication Channel (SCC): A CCh dedicated for
    control plane communications. The SCC can be used for GMPLS/ASON
    signaling and/or other control plane messages (e.g., routing
    messages).
 
    Signaling Communication Network (SCN): A DCN supporting control
    plane communication is referred to as a Signaling Communication
    Network (SCN).
 
 2. Management Interface Requirements
 
    This document does not specify a preferred management interface
    protocol to be used as the standard protocol for managing MPLS-TP
    networks. Managing an end-to-end connection across multiple
    operator domains where one domain is managed (for example) via
    NETCONF ([16]) or SNMP ([17]), and another domain via CORBA
    ([18]), is allowed.
 
       1) For the management interface to the management system, an
         MPLS-TP NE MAY actively support more than one management
         protocol in any given deployment.
 
    For example, an operator can use one protocol for configuration
    of an MPLS-TP NE and another for monitoring. The protocols to be
    supported are at the discretion of the operator.
 
 3. Management Communication Channel (MCC) Requirements
 
       1) Specifications SHOULD define support for management
         connectivity with remote MPLS-TP domains and NEs, as well as
         with termination points located in NEs under the control of
         a third party network operator.  See ITU-T G.8601 [23] for
         example scenarios in multi-carrier multi-transport-
         technology environments.
 
       2) For management purpose, every MPLS-TP NE MUST connect to an
         OS. The connection MAY be direct (e.g. - via a software,
         hardware or proprietary protocol connection) or indirect
         (via another MPLS-TP NE). In this document, any management
         connection that is not via another MPLS-TP NE is a direct
         management connection.  When an MPLS-TP NE is connected
         indirectly to an OS, an MCC MUST be supported between that
         MPLS-TP NE and any MPLS-TP NE(s) used to provide the
         connection to an OS.
 
 
 
 
 
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 4. Management Communication Network (MCN) Requirements
 
    Entities of the MPLS-TP management plane communicate via a DCN,
    or more specifically via the MCN. The MCN connects management
    systems with management systems, management systems with MPLS-TP
    NEs, and (in the indirect connectivity case discussed in section
    3) MPLS-TP NEs with MPLS-TP NEs.
 
    RFC 5586 [14] defines a Generic Associated Channel (G-ACh) to
    enable the realization of a communication channel (CCh) between
    adjacent MPLS-TP NEs for management and control. Reference [10]
    describes how the G-ACh can be used to provide infrastructure
    that forms part of the MCN and SCN. It also explains how MCN and
    SCN messages are encapsulated, carried on the G-ACh, and
    decapsulated for delivery to management or signaling/routing
    control plane components on a label switching router (LSR).
 
    ITU-T G.7712/Y.1703 [6], section 7, describes the transport DCN
    architecture and requirements.
 
       1) The MPLS-TP MCN MUST support the requirements (in reference
          [6]) for:
 
         a) CCh access functions specified in section 7.1.1;
 
         b) MPLS-TP SCC data-link layer termination functions
            specified in section 7.1.2.3;
 
         c) MPLS-TP MCC data-link layer termination functions
            specified in section 7.1.2.4;
 
         d) Network layer PDU into CCh data-link frame encapsulation
            functions specified in section 7.1.3;
 
         e) Network layer PDU forwarding (7.1.6), interworking (7.1.7)
            and encapsulation (7.1.8) functions, as well as tunneling
            (7.1.9) and routing (7.1.10) functions specified in [6].
 
    As a practical matter, MCN connections will typically have
    addresses. See the section on Identifiers in [8] for further
    information.
 
    In order to have the MCN operate properly, a number of management
    functions for the MCN are needed, including:
 
 
 
 
 
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       . Retrieval of DCN network parameters to ensure compatible
         functioning, e.g. packet size, timeouts, quality of service,
         window size, etc.;
 
       . Establishment of message routing between DCN nodes;
 
       . Management of DCN network addresses;
 
       . Retrieval of operational status of the DCN at a given node;
 
       . Capability to enable/disable access by an NE to the DCN.
         Note that this is to allow isolating a malfunctioning NE
         from impacting the rest of the network.
 
 5. Fault Management Requirements
 
    The Fault Management functions within an MPLS-TP NE enable the
    supervision, detection, validation, isolation, correction, and
    reporting of abnormal operation of the MPLS-TP network and its
    environment.
 
 5.1. Supervision Function
 
    The supervision function analyses the actual occurrence of a
    disturbance or fault for the purpose of providing an appropriate
    indication of performance and/or detected fault condition to
    maintenance personnel and operations systems.
 
       1) The MPLS-TP NE MUST support supervision of the OAM
         mechanisms that are deployed for supporting the OAM
         requirements defined in [3].
 
       2) The MPLS-TP NE MUST support the following data-plane
         forwarding path supervision functions:
 
         a) Supervision of loop-checking functions used to detect
            loops in the data-plane forwarding path (which result in
            non-delivery of traffic, wasting of forwarding resources
            and unintended self-replication of traffic);
 
         b) Supervision of failure detection;
 
       3) The MPLS-TP NE MUST support the capability to configure
         data-plane forwarding path related supervision mechanisms to
         perform on-demand or proactively.
 
 
 
 
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       4) The MPLS-TP NE MUST support supervision for software
         processing - e.g., processing faults, storage capacity,
         version mismatch, corrupted data and out of memory problems,
         etc.
 
       5) The MPLS-TP NE MUST support hardware-related supervision for
         interchangeable and non-interchangeable unit, cable, and
         power problems.
 
       6) The MPLS-TP NE SHOULD support environment-related
         supervision for temperature, humidity, etc.
 
 5.2. Validation Function
 
    Validation is the process of integrating Fault Cause indications
    into Failures. A Fault Cause Indication (FCI) indicates a limited
    interruption of the required transport function. A Fault Cause is
    not reported to maintenance personnel because it might exist only
    for a very short time. Note that some of these events are summed
    up in the Performance Monitoring process (see section 7), and
    when this sum exceeds a configured value, a threshold crossing
    alert (report) can be generated.
 
    When the Fault Cause lasts long enough, an inability to perform
    the required transport function arises. This failure condition is
    subject to reporting to maintenance personnel and/or an OS
    because corrective action might be required. Conversely, when the
    Fault Cause ceases after a certain time, clearing of the Failure
    condition is also subject to reporting.
 
       1) The MPLS-TP NE MUST perform persistency checks on fault
         causes before it declares a fault cause a failure.
 
       2) The MPLS-TP NE SHOULD provide a configuration capability for
         control parameters associated with performing the
         persistency checks described above.
 
       3) An MPLS-TP NE MAY provide configuration parameters to
         control reporting, and clearing, of failure conditions.
 
       4) A data-plane forwarding path failure MUST be declared if the
         fault cause persists continuously for a configurable time
         (Time-D). The failure MUST be cleared if the fault cause is
         absent continuously for a configurable time (Time-C).
 
    Note: As an example, the default time values might be as follows:
 
 
 
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       Time-D = 2.5 +/- 0.5 seconds
 
       Time-C = 10 +/- 0.5 seconds
 
    These time values are as defined in G.7710 [1].
 
       5) MIBs - or other object management semantics specifications -
         defined to enable configuration of these timers SHOULD
         explicitly provide default values and MAY provide guidelines
         on ranges and value determination methods for scenarios
         where the default value chosen might be inadequate. In
         addition, such specifications SHOULD define the level of
         granularity at which tables of these values are to be
         defined.
 
       6) Implementations MUST provide the ability to configure the
         preceding set of timers, and SHOULD provide default values
         to enable rapid configuration. Suitable default values,
         timer ranges, and level of granularity are out of scope in
         this document and form part of the specification of fault
         management details. Timers SHOULD be configurable per NE for
         broad categories (for example, defects and/or fault causes),
         and MAY be configurable per-interface on an NE and/or per
         individual defect/fault cause.
 
       7) The failure declaration and clearing MUST be time stamped.
         The time-stamp MUST indicate the time at which the fault
         cause is activated at the input of the fault cause
         persistency (i.e. defect-to-failure integration) function,
         and the time at which the fault cause is deactivated at the
         input of the fault cause persistency function.
 
 5.3. Alarm Handling Function
 
 5.3.1. Alarm Severity Assignment
 
    Failures can be categorized to indicate the severity or urgency
    of the fault.
 
       1) An MPLS-TP NE SHOULD support the ability to assign severity
         (e.g., Critical, Major, Minor, Warning) to alarm conditions
         via configuration.
 
    See G.7710 [1], section 7.2.2 for more detail on alarm severity
    assignment. For additional discussion of Alarm Severity
    management, see discussion of alarm severity in RFC 3877 [11].
 
 
 
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 5.3.2. Alarm Suppression
 
    Alarms can be generated from many sources, including OAM, device
    status, etc.
 
       1) An MPLS-TP NE MUST support suppression of alarms based on
         configuration.
 
 5.3.3. Alarm Reporting
 
    Alarm Reporting is concerned with the reporting of relevant
    events and conditions, which occur in the network (including the
    NE, incoming signal, and external environment).
 
    Local reporting is concerned with automatic alarming by means of
    audible and visual indicators near the failed equipment.
 
       1) An MPLS-TP NE MUST support local reporting of alarms.
 
       2) The MPLS-TP NE MUST support reporting of alarms to an OS.
         These reports are either autonomous reports (notifications)
         or reports on request by maintenance personnel. The MPLS-TP
         NE SHOULD report local (environmental) alarms to a network
         management system.
 
       3) An MPLS-TP NE supporting one or more other networking
         technologies (e.g. - Ethernet, SDH/SONET, MPLS) over MPLS-TP
         MUST be capable of translating an MPLS-TP defects into
         failure conditions that are meaningful to the client layer,
         as described in RFC 4377 [2], section 4.7.
 
 5.3.4. Alarm Reporting Control
 
    Alarm Reporting Control (ARC) supports an automatic in-service
    provisioning capability. Alarm reporting can be turned off on a
    per-managed entity (e.g., LSP) basis to allow sufficient time for
    customer service testing and other maintenance activities in an
    "alarm free" state. Once a managed entity is ready, alarm
    reporting is automatically turned on.
 
       1) An MPLS-TP NE SHOULD support the Alarm Reporting Control
         function for controlling the reporting of alarm conditions.
 
    See G.7710 [1] (section 7.1.3.2) and RFC 3878 [24] for more
    information about ARC.
 
 
 
 
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 6. Configuration Management Requirements
 
    Configuration Management provides functions to identify, collect
    data from, provide data to and control NEs.  Specific
    configuration tasks requiring network management support include
    hardware and software configuration, configuration of NEs to
    support transport paths (including required working and
    protection paths), and configuration of required path
    integrity/connectivity and performance monitoring (i.e. - OAM).
 
 6.1. System Configuration
 
       1) The MPLS-TP NE MUST support the configuration requirements
         specified in G.7710 [1] section 8.1 for hardware.
 
       2) The MPLS-TP NE MUST support the configuration requirements
         specified in G.7710 [1] section 8.2 for software.
 
       3) The MPLS-TP NE MUST support the configuration requirements
         specified in G.7710 [1] section 8.13.2.1 for local real time
         clock functions.
 
       4) The MPLS-TP NE MUST support the configuration requirements
         specified in G.7710 [1] section 8.13.2.2 for local real time
         clock alignment with external time reference.
 
       5) The MPLS-TP NE MUST support the configuration requirements
         specified in G.7710 [1] section 8.13.2.3 for performance
         monitoring of the clock function.
 
 6.2. Control Plane Configuration
 
       1) If a control plane is supported in an implementation of
         MPLS-TP, the MPLS-TP NE MUST support the configuration of
         MPLS-TP control plane functions by the management plane.
         Further detailed requirements will be provided along with
         progress in defining the MPLS-TP control plane in
         appropriate specifications.
 
 6.3. Path Configuration
 
       1) In addition to the requirement to support static
         provisioning of transport paths (defined in [7], section 2.1
         - General Requirements - requirement 18), an MPLS-TP NE MUST
         support the configuration of required path performance
         characteristic thresholds (e.g. - Loss Measurement <LM>,
 
 
 
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         Delay Measurement <DM> thresholds) necessary to support
         performance monitoring of the MPLS-TP service(s).
 
       2) In order to accomplish this, an MPLS-TP NE MUST support
         configuration of LSP information (such as an LSP identifier
         of some kind) and/or any other information needed to
         retrieve LSP status information, performance attributes,
         etc.
 
       3) If a control plane is supported, and that control plane
         includes support for control-plane/management-plane hand-off
         for LSP setup/maintenance, the MPLS-TP NE MUST support
         management of the hand-off of Path control. See, for
         example, references [19] and [20].
 
       4) Further detailed requirements SHALL be provided along with
         progress in defining the MPLS-TP control plane in
         appropriate specifications.
 
       5) If MPLS-TP transport paths cannot be statically provisioned
         using MPLS LSP and pseudo-wire management tools (either
         already defined in standards or under development), further
         management specifications MUST be provided as needed.
 
 6.4. Protection Configuration
 
       1) The MPLS-TP NE MUST support configuration of required path
         protection information as follows:
 
       . designate specifically identified LSPs as working or
          protecting LSPs;
 
       . define associations of working and protecting paths;
 
       . operate/release manual protection switching;
 
       . operate/release force protection switching;
 
       . operate/release protection lockout;
 
       . set/retrieve Automatic Protection Switching (APS)
          parameters, including -
 
         o  Wait to Restore time,
 
         o  Protection Switching threshold information.
 
 
 
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 6.5. OAM Configuration
 
       1) The MPLS-TP NE MUST support configuration of the OAM
         entities and functions specified in [3].
 
       2) The MPLS-TP NE MUST support the capability to choose which
         OAM functions are enabled.
 
       3) For enabled OAM functions, the MPLS-TP NE MUST support the
         ability to associate OAM functions with specific maintenance
         entities.
 
       4) The MPLS-TP NE MUST support the capability to configure the
         OAM entities/functions as part of LSP setup and tear-down,
         including co-routed bidirectional point-to-point, associated
         bidirectional point-to-point, and uni-directional (both
         point-to-point and point-to-multipoint) connections.
 
       5) The MPLS-TP NE MUST support the configuration of maintenance
         entity identifiers (e.g. MEP ID and MIP ID) for the purpose
         of LSP connectivity checking.
 
       6) The MPLS-TP NE MUST support configuration of OAM parameters
         to meet their specific operational requirements, such as
         whether -
 
         a) one-time on-demand immediately or
 
         b) one-time on-demand pre-scheduled or
 
         c) on-demand periodically based on a specified schedule or
 
         d) proactive on-going.
 
       7) The MPLS-TP NE MUST support the enabling/disabling of the
         connectivity check processing. The connectivity check
         process of the MPLS-TP NE MUST support provisioning of the
         identifiers to be transmitted and the expected identifiers.
 
 7. Performance Management Requirements
 
    Performance Management provides functions for the purpose of
    Maintenance, Bring-into-service, Quality of service, and
    statistics gathering.
 
 
 
 
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    This information could be used, for example, to compare behavior
    of the equipment, MPLS-TP NE or network at different moments in
    time to evaluate changes in network performance.
 
    ITU-T Recommendation G.7710 [1] provides transport performance
    monitoring requirements for packet-switched and circuit-switched
    transport networks with the objective of providing coherent and
    consistent interpretation of the network behavior in a multi-
    technology environment. The performance management requirements
    specified in this document are driven by such an objective.
 
 7.1. Path Characterization Performance Metrics
 
       1) It MUST be possible to determine when an MPLS-TP based
         transport service is available and when it is unavailable.
 
    From a performance perspective, a service is unavailable if there
    is an indication that performance has degraded to the extent that
    a configurable performance threshold has been crossed and the
    degradation persists long enough (i.e. - the indication persists
    for some amount of time - which is either configurable, or well-
    known) to be certain it is not a measurement anomaly.
 
    Methods, mechanisms and algorithms for exactly how unavailability
    is to be determined - based on collection of raw performance data
    - are out of scope for this document.
 
       2) The MPLS-TP NE MUST support collection and reporting of raw
         performance data that MAY be used in determining the
         unavailability of a transport service.
 
       3) MPLS-TP MUST support the determination of the unavailability
         of the transport service. The result of this determination
         MUST be available via the MPLS-TP NE (at service termination
         points), and determination of unavailability MAY be
         supported by the MPLS-TP NE directly. To support this
         requirement, the MPLS-TP NE management information model
         MUST include objects corresponding to availability-state of
         services.
 
    Transport network unavailability is based on Severely Errored
    Seconds (SES) and Unavailable Seconds (UAS). ITU-T is
    establishing definitions of unavailability generically applicable
    to packet transport technologies, including MPLS-TP, based on SES
    and UAS. Note that SES and UAS are already defined for Ethernet
    transport networks in ITU-T Recommendation Y.1563 [25].
 
 
 
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       4) The MPLS-TP NE MUST support collection of loss measurement
         (LM) statistics.
 
       5) The MPLS-TP NE MUST support collection of delay measurement
         (DM) statistics.
 
       6) The MPLS-TP NE MUST support reporting of Performance
         degradation via fault management for corrective actions.
 
    "Reporting" in this context could mean:
 
          . reporting to an autonomous protection component to
            trigger protection switching,
 
          . reporting via a craft interface to allow replacement of a
            faulty component (or similar manual intervention),
 
          . etc.
 
       7) The MPLS-TP NE MUST support reporting of performance
         statistics on request from a management system.
 
 7.2. Performance Measurement Instrumentation
 
 7.2.1. Measurement Frequency
 
       1) For performance measurement mechanisms that support both
         proactive and on-demand modes, the MPLS-TP NE MUST support
         the capability to be configured to operate on-demand or
         proactively.
 
 7.2.2. Measurement Scope
 
    On measurement of packet loss and loss ratio:
 
       1) For bidirectional (both co-routed and associated) P2P
          connections -
 
          a) on-demand measurement of single-ended packet loss, and
            loss ratio, measurement is REQUIRED;
 
          b) proactive measurement of packet loss, and loss ratio,
            measurement for each direction is REQUIRED.
 
       2) For unidirectional (P2P and P2MP) connection, proactive
          measurement of packet loss, and loss ratio, is REQUIRED.
 
 
 
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    On Delay measurement:
 
       3) For unidirectional (P2P and P2MP) connection, on-demand
       measurement of delay measurement is REQUIRED.
 
       4) For co-routed bidirectional (P2P) connection, on-demand
       measurement of one-way and two-way delay is REQUIRED.
 
       5) For associated bidirectional (P2P) connection, on-demand
       measurement of one-way delay is REQUIRED.
 
 8. Security Management Requirements
 
       1) The MPLS-TP NE MUST support secure management and control
          planes.
 
 8.1. Management Communication Channel Security
 
       1) Secure communication channels MUST be supported for all
         network traffic and protocols used to support management
         functions.  This MUST include, at least, protocols used for
         configuration, monitoring, configuration backup, logging,
         time synchronization, authentication, and routing.
 
       2) The MCC MUST support application protocols that provide
         confidentiality and data integrity protection.
 
       3) The MPLS-TP NE MUST support the following:
 
         a) Use of open cryptographic algorithms (See RFC 3871 [4])
 
         b) Authentication - allow management connectivity only from
            authenticated entities.
 
         c) Authorization - allow management activity originated by an
            authorized entity, using (for example) an Access Control
            List (ACL).
 
         d) Port Access Control - allow management activity received
            on an authorized (management) port.
 
 8.2. Signaling Communication Channel Security
 
    Security requirements for the SCC are driven by considerations
    similar to MCC requirements described in section 8.1.
 
 
 
 
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    Security Requirements for the control plane are out of scope for
    this document and are expected to be defined in the appropriate
    control plane specifications.
 
       1) Management of control plane security MUST be defined in the
         appropriate control plane specifications..
 
 8.3. Distributed Denial of Service
 
    A Denial of Service (DoS) attack is an attack that tries to
    prevent a target from performing an assigned task, or providing
    its intended service(s), through any means. A Distributed DoS
    (DDoS) can multiply attack severity (possibly by an arbitrary
    amount) by using multiple (potentially compromised) systems to
    act as topologically (and potentially geographically) distributed
    attack sources. It is possible to lessen the impact and potential
    for DoS and DDoS by using secure protocols, turning off
    unnecessary processes, logging and monitoring, and ingress
    filtering.  RFC 4732 [26] provides background on DoS in the
    context of the Internet.
 
       1) An MPLS-TP NE MUST support secure management protocols and
         SHOULD do so in a manner that reduces potential impact of a
         DoS attack.
 
       2) An MPLS-TP NE SHOULD support additional mechanisms that
         mitigate a DoS (or DDoS) attack against the management
         component while allowing the NE to continue to meet its
         primary functions.
 
 9. Security Considerations
 
    Section 8 includes a set of security requirements that apply to
    MPLS-TP network management.
 
       1) Solutions MUST provide mechanisms to prevent unauthorized
         and/or unauthenticated access to management capabilities and
         private information by network elements, systems or users.
 
    Performance of diagnostic functions and path characterization
    involves extracting a significant amount of information about
    network construction that the network operator might consider
    private.
 
 
 
 
 
 
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 10. IANA Considerations
 
    There are no IANA actions associated with this document.
 
 11. Acknowledgments
 
    The authors/editors gratefully acknowledge the thoughtful review,
    comments and explanations provided by Adrian Farrel, Alexander
    Vainshtein, Andrea Maria Mazzini, Ben Niven-Jenkins, Bernd
    Zeuner, Dan Romascanu, Daniele Ceccarelli, Diego Caviglia, Dieter
    Beller, He Jia, Leo Xiao, Maarten Vissers, Neil Harrison, Rolf
    Winter, Yoav Cohen and Yu Liang.
 
 12. References
 
 12.1. Normative References
 
    [1]   ITU-T Recommendation G.7710/Y.1701, "Common equipment
          management function requirements", July, 2007.
 
    [2]   Nadeau, T., et al, "Operations and Management (OAM)
          Requirements for Multi-Protocol Label Switched (MPLS)
          Networks", RFC 4377, February 2006.
 
    [3]   Vigoureux, M., et al, "Requirements for OAM in MPLS
          Transport Networks", draft-ietf-mpls-tp-oam-requirements,
          work in progress.
 
    [4]   Jones, G., "Operational Security Requirements for Large
          Internet Service Provider (ISP) IP Network Infrastructure",
          RFC 3871, September 2004.
 
    [5]   Bradner, S., "Key words for use in RFCs to Indicate
          Requirement Levels", RFC 2119, March 1997.
 
    [6]   ITU-T Recommendation G.7712/Y.1703, "Architecture and
          specification of data communication network", June 2008.
 
    [7]   Niven-Jenkins, B. et al, "MPLS-TP Requirements", draft-
          ietf-mpls-tp-requirements, work in progress.
 
    [8]   Bocci, M. et al, "A Framework for MPLS in Transport
          Networks", draft-ietf-mpls-tp-framework, work in progress.
 
    [9]   Mansfield, S. et al, "MPLS-TP Network Management
          Framework", draft-ietf-mpls-tp-nm-framework, work in
          progress.
 
 
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 12.2. Informative References
 
    [10]  Beller, D., et al, "An Inband Data Communication Network
          For the MPLS Transport Profile", draft-ietf-mpls-tp-gach-
          dcn, work in progress.
 
    [11]  Chisholm, S. and D. Romascanu, "Alarm Management
          Information Base (MIB)", RFC 3877, September 2004.
 
    [12]  ITU-T Recommendation M.20, "Maintenance philosophy for
          telecommunication networks", October 1992.
 
    [13]  Telcordia, "Network Maintenance: Network Element and
          Transport Surveillance Messages" (GR-833-CORE), Issue 5,
          August 2004.
 
    [14]  Bocci, M. et al, "MPLS Generic Associated Channel", RFC
          5586, June 2009.
 
    [15]  Harrington, D., "Guidelines for Considering Operations and
          Management of New Protocols and Protocol Extensions",
          draft-ietf-opsawg-operations-and-management, work in
          progress.
 
    [16]  Enns, R. et al, "NETCONF Configuration Protocol", draft-
          ietf-netconf-4741bis, work in progress.
 
    [17]  Presuhn, R. et al, "Version 2 of the Protocol Operations
          for the Simple Network Management Protocol (SNMP)", RFC
          3416, December 2002.
 
    [18]  OMG Document formal/04-03-12, "The Common Object Request
          Broker: Architecture and Specification", Revision 3.0.3.
          March 12, 2004.
 
    [19]  Caviglia, D. et al, "Requirements for the Conversion
          between Permanent Connections and Switched Connections in a
          Generalized Multiprotocol Label Switching (GMPLS) Network",
          RFC 5493, April 2009.
 
    [20]  Caviglia, D. et al, "RSVP-TE Signaling Extension For The
          Conversion Between Permanent Connections And Soft Permanent
          Connections In A GMPLS Enabled Transport Network", draft-
          ietf-ccamp-pc-spc-rsvpte-ext, work in progress.
 
 
 
 
 
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    [21]  ITU-T Recommendation G.806, "Characteristics of transport
          equipment - Description methodology and generic
          functionality", January, 2009.
 
    [22]  ITU-T Recommendation Y.1731, "OAM functions and mechanisms
          for Ethernet based networks", February, 2008.
 
    [23]  ITU-T Recommendation G.8601, "Architecture of service
          management in multi bearer, multi carrier environment",
          June 2006.
 
    [24]  Lam, H., et al, "Alarm Reporting Control Management
          Information Base (MIB)", RFC 3878, September 2004.
 
    [25]  ITU-T Recommendation Y.1563, "Ethernet frame transfer and
          availability performance", January 2009.
 
    [26]  Handley, M., et al, "Internet Denial-of-Service
          Considerations", RFC 4732, November 2006.
 
  Authors' Addresses
 
 
    Eric Gray
    Ericsson
    900 Chelmsford Street
    Lowell, MA, 01851
    Phone: +1 978 275 7470
    Email: Eric.Gray@Ericsson.com
 
    Scott Mansfield
    Ericsson
    250 Holger Way
    San Jose CA, 95134
    +1 724 931 9316
    EMail: Scott.Mansfield@Ericsson.com
 
    Hing-Kam (Kam) Lam
    Alcatel-Lucent
    600-700 Mountain Ave
    Murray Hill, NJ, 07974
    Phone: +1 908 582 0672
    Email: hklam@Alcatel-Lucent.com
 
 
 
 
 
 
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 Contributor's Address
 
 
    Adrian Farrel
    Old Dog Consulting
    Email: adrian@olddog.co.uk
 
 Copyright Statement
 
    Copyright (c) 2009 IETF Trust and the persons identified as the
    document authors.  All rights reserved.
 
    This document is subject to BCP 78 and the IETF Trust's Legal
    Provisions Relating to IETF Documents in effect on the date of
    publication of this document (http://trustee.ietf.org/license-
    info).  Please review these documents carefully, as they describe
    your rights and restrictions with respect to this document.
 
 Acknowledgment
 
    Funding for the RFC Editor function is currently provided by the
    Internet Society.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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 Appendix A- Communication Channel (CCh) Examples
 
    A CCh can be realized in a number of ways.
 
    1. The CCh can be provided by a link in a physically distinct
    network.  That is, a link that is not part of the transport
    network that is being managed. For example, the nodes in the
    transport network can be interconnected in two distinct physical
    networks: the transport network and the DCN.
 
    This is a "physically distinct out-of-band CCh".
 
    2. The CCh can be provided by a link in the transport network
    that is terminated at the ends of the DCC and which is capable of
    encapsulating and terminating packets of the management
    protocols.  For example, in MPLS-TP a single-hop LSP might be
    established between two adjacent nodes, and that LSP might be
    capable of carrying IP traffic. Management traffic can then be
    inserted into the link in an LSP parallel to the LSPs that carry
    user traffic.
 
    This is a "physically shared out-of-band CCh."
 
    3. The CCh can be supported as its native protocol on the
    interface alongside the transported traffic. For example, if an
    interface is capable of sending and receiving both MPLS-TP and
    IP, the IP-based management traffic can be sent as native IP
    packets on the interface.
 
    This is a "shared interface out-of-band CCh".
 
    4. The CCh can use overhead bytes available on a transport
    connection. For example, in TDM networks there are overhead bytes
    associated with a data channel, and these can be used to provide
    a CCh. It is important to note that the use of overhead bytes
    does not reduce the capacity of the associated data channel.
 
    This is an "overhead-based CCh".
 
    This alternative is not available in MPLS-TP because there is no
    overhead available.
 
    5. The CCh can provided by a dedicated channel associated with
    the data link. For example, the generic associated label (GAL)
    [14] can be used to label DCC traffic being exchanged on a data
 
 
 
 
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    link between adjacent transport nodes, potentially in the absence
    of any data LSP between those nodes.
 
    This is a "data link associated CCh".
 
    It is very similar to case 2, and by its nature can only span a
    single hop in the transport network.
 
    6. The CCh can be provided by a dedicated channel associated with
    a data channel. For example, in MPLS-TP the GAL [14] can be
    imposed under the top label in the label stack for an MPLS-TP LSP
    to create a channel associated with the LSP that can carry
    management traffic. This CCh requires the receiver to be capable
    of demultiplexing management traffic from user traffic carried on
    the same LSP by use of the GAL.
 
    This is a "data channel associated CCh".
 
    7. The CCh can be provided by mixing the management traffic with
    the user traffic such that is indistinguishable on the link
    without deep-packet inspection. In MPLS-TP this could arise if
    there is a data-carrying LSP between two nodes, and management
    traffic is inserted into that LSP. This approach requires that
    the termination point of the LSP is able to demultiplex the
    management and user traffic. Such might be possible in MPLS-TP if
    the MPLS-TP LSP was carrying IP user traffic.
 
    This is an "in-band CCh".
 
    These realizations can be categorized as:
 
       A. Out-of-fiber, out-of-band (types 1 and 2)
       B. In-fiber, out-of-band (types 2, 3, 4, and 5)
       C. In-band (types 6 and 7)
 
    The MCN and SCN are logically separate networks and can be
    realized by the same DCN or as separate networks. In practice,
    that means that, between any pair of nodes, the MCC and SCC can
    be the same link or separate links.
 
    It is also important to note that the MCN and SCN do not need to
    be categorised as in-band, out-of-band, etc. This definition only
    applies to the individual links, and it is possible for some
    nodes to be connected in the MCN or SCN by one type of link, and
    other nodes by other types of link. Furthermore, a pair of
 
 
 
 
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    adjacent nodes can be connected by multiple links of different
    types.
 
    Lastly note that the division of DCN traffic between links
    between a pair of adjacent nodes is purely an implementation
    choice. Parallel links can be deployed for DCN resilience or load
    sharing. Links can be designated for specific use. For example,
    so that some links carry management traffic and some carry
    control plane traffic, or so that some links carry signaling
    protocol traffic while others carry routing protocol traffic.
 
    It is important to note that the DCN can be a routed network with
    forwarding capabilities, but that this is not a requirement. The
    ability to support forwarding of management or control traffic
    within the DCN can substantially simplify the topology of the DCN
    and improve its resilience, but does increase the complexity of
    operating the DCN.
 
    See also RFC 3877 [11], ITU-T M.20 [12], and Telcordia document
    GR-833-CORE [13] for further information.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
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