Generic YANG Data Model for Connection Oriented Operations, Administration, and Maintenance(OAM) protocols

Generic YANG Data Model for Connection Oriented Operations, Administration, and Maintenance(OAM) protocols CISCO Systems

510 McCarthy Blvd Milpitas CA 95035 USA dekumar@cisco.com

Huawei

101 Software Avenue, Yuhua District Nanjing Jiangsu 210012 China bill.wu@huawei.com

Huawei Technologies,Co.,Ltd

101 Software Avenue, Yuhua District Nanjing 210012 China wangzitao@huawei.com

OPS Area This document presents a base YANG Data model for connection oriented OAM protocols. It provides a technology-independent abstraction of key OAM constructs for such protocols. The model presented here can be extended to include technology specific details. This guarantees uniformity in the management of OAM protocols and provides support for nested OAM workflows (i.e., performing OAM functions at different levels through a unified interface)

Operations, Administration, and Maintenance (OAM) are important networking functions that allow operators to: Monitor networks connections (Connectivity Verification, Continuity Check). Troubleshoot failures (Fault verification and localization). Monitor Performance An overview of OAM tools is presented in . Over the years, many technologies have developed similar tools for fault and performance management. Connectivity Fault Management is a well-established OAM standard that is widely adopted for Ethernet networks. ITU-T , MEF Service OAM, MPLS-TP , TRILL all define OAM mechanisms based on the manageability frame work of CFM . Given the wide adoption of the underlying OAM concepts defined in CFM , it is a reasonable choice to develop the unified management framework for connection oriented OAM based on those concepts. In this document, we take the CFM model and extend it to a technology independent framework and define the corresponding YANG model accordingly. The YANG model presented in this document is the base model for connection oriented OAM protocols and supports generic continuity check, connectivity verification and path discovery (traceroute). The generic YANG model for connection oriented OAM is designed to be extensible to other connection oriented technologies. Technology dependent nodes and remote process call (RPC) commands are defined in technology specific YANG models, which use and extend the base model defined here. As an example, VXLAN uses source UDP port number for flow entropy, while TRILL uses either MAC addresses, the VLAN tag or fine grain label, and/or IP addresses for flow entropy in the hashing for multipath selection. To capture this variation, corresponding YANG models would define the applicable structures as augmentation to the generic base model presented here. This accomplishes three goals: First it keeps each YANG model smaller and more manageable. Second, it allows independent development of corresponding YANG models. Third, implementations can limit support to only the applicable set of YANG models. (e.g. TRILL RBridge may only need to implement Generic model and the TRILL YANG model). All implementations that follow the YANG framework presented in this document MUST implement the generic connection oriented YANG model presented here. The YANG data model presented in this document is generated at the management layer. Encapsulations and state machines may differ according to each OAM protocol. A user who wishes to issues a Continuity Check command or a Loopback or initiate a performance monitoring session can do so in the same manner regardless of the underlying protocol or technology or specific vendor implementation. As an example, consider a scenario where Loopback from device A to Device B fails. Between device A and B there are IEEE 802.1 bridges a, b and c. Let's assume a,b and c are using CFM . Upon detecting the Loopback failures, a user may decide to drill down to the lower level at different segments of the path and issue the corresponding fault verification (LBM) and fault isolation (LTM) tools, using the same API. This ability to drill down to a lower layer of the protocol stack at a specific segment within a path for fault localization and troubleshooting is referred to as "nested OAM workflow". It is a useful concept that leads to efficient network troubleshooting and maintenance workflows. The connection oriented OAM YANG model presented in this document facilitates that without needing changes to the underlying protocols.

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 . In this document, these words will appear with that interpretation only when in ALL CAPS. Lower case uses of these words are not to be interpreted as carrying significance. The following notations are used within the data tree and carry the meaning as below. Each node is printed as:

<status> <flags> <name> <opts> <type> <status> is one of: + for current <flags> is one of: rw for configuration data ro for non-configuration data -x for rpcs -n for notifications -w for writable <name> is the name of the node If the node is augmented into the tree from another module, its name is printed as <prefix>:<name>.

<opts> is one of: ? for an optional leaf or choice ! for a presence container * for a leaf-list or list [<keys>] for a list's keys (choice)/:(case) Parentheses enclose choice and case nodes, and case nodes are also marked with a colon (":") <type> is the name of the type for leafs and leaf-lists

- Continuity Check Message . - Equal Cost Multipath. - Loopback Message . - Maintenance Point . - Maintenance End Point (Maintenance association End Point , MEG End Points ). - Maintenance Intermediate Point (Maintenance domain Intermediate Point , MEG Intermediate Point ). - Maintenance Association . - Maintenance Domain - Maintenance Entity Group - Multi-destination Tree Verification Message. - Operations, Administration, and Maintenance . - Transparent Interconnection of Lots of Links . - Connectivity Fault Management . - Remote Process Call. - Continuity Check . - Connectivity Verification .

- Continuity Checks are used to verify that a destination is reachable and therefore also referred to as reachability verification. - Connectivity Verification are used to verify that a destination is connected. It are also referred to as path verification and used to verify not only that the two MPs are connected, but also that they are connected through the expected path, allowing detection of unexpected topology changes. - The proactive OAM refers to OAM actions which are carried out continuously to permit proactive reporting of fault. Proactive OAM method requires persistent configuration. - The on-demand OAM refers to OAM actions which are initiated via manual intervention for a limited time to carry out diagnostics. On-demand OAM method requires only transient configuration.

In this document we define a generic YANG model for connection oriented OAM protocols. The YANG model defined here is generic in a sense that other technologies can extend it for technology specific needs. The Generic YANG model acts as the root for other OAM YANG models. This allows users to traverse between different OAM protocols with ease through a uniform API set. This also enables a nested OAM workflow. Figure 1 depicts the relationship of different OAM YANG models to the Generic YANG Model for connection oriented OAM. The Generic YANG model for OAM provides a framework where technology- specific YANG models can inherit constructs from the base YANG models without needing to redefine them within the sub-technology. Figure 1 depicts relationship of different YANG modules.

+----------+ |Connection| | Oriented | | gen | |OAM YANG | +-+-+-+-+-++ | | | +------------------------------------------+ | | | +-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+ | TRILL | | MPLS-TP | . . .| foo | |OAM YANG | |OAM YANG | |OAM YANG | +-+-+-+-+-+ +-+-+-+-+-+ +-+-+-+-+-+ | | | | | +-+-+-+-+-+ | | . . .| foo | | | |sub tech | | | +-+-+-+-+-+ | | | | | | +-------------------------------------------------------+ | Uniform API | +-------------------------------------------------------+

In this document we adopt the concepts of the CFM model and structure it such that it can be adapted to different connection oriented OAM protocols. At the top of the Model is the Maintenance Domain. Each Maintenance Domain is associated with a Maintenance Name and a Domain Level. Under each Maintenance Domain there is one or more Maintenance Association (MA). In TRILL this can be per Fine-Grained Label or for VPLS this can be per VPLS instance . Under each MA, there can be two or more MEPs (Maintenance End Points). MEPs are addressed by their respective technology specific address identifiers. The YANG model presented here provides flexibility to accommodate different addressing schemes. In the vertical direction orthogonal to the Maintenance Domain, presented are the commands. Those, in YANG terms, are the RPC commands. These RPC commands provide uniform APIs for continuity check, connectivity verification, path discovery(traceroute) and their equivalents as well as other OAM commands. The OAM entities in the generic YANG model defined here will be either explicitly or implicitly configured using any of the OAM tools. The OAM tools used here are limited to OAM toolset specified in section 5.1 of . In order to facilitate zero-touch experience, this document defines a default mode of OAM. The default mode of OAM is referred to as the Base Mode and specifies default values for each of model parameters, such as Maintenance Domain Level, Name of the Maintenance Association, Addresses of MEPs and so on. The default values of these depend on the technology. Base Mode for TRILL is defined in . Base mode for other technologies and future extensions developed in IETF will be defined in their corresponding documents. It is important to note that, no specific enhancements are needed in the YANG model to support Base Mode. Implementations that comply with this document, by default implement the data nodes of the applicable technology. Data nodes of the Base Mode are read-only nodes.

The container "domains" is the top level container within the gen-oam module. Within the container "domains", separate list is maintained per MD. The MD list uses the key MD-name-string for indexing. MD-name-string is a leaf and derived from type string. Additional name formats as defined in or other standards can be included by association of the MD-name-format with an identity-ref. MD-name-format indicates the format of the augmented MD-names. MD-name is presented as choice/case construct. Thus, it is easily augmentable by derivative work.

Within a given Maintenance Domain there can be one or more Maintenance Associations (MA(s)). MAs are represented as a list and indexed by the MA-name-string. Similar to MD-name defined previously, additional name formats can be added by augmenting the name-format identity-ref and adding applicable case statements to MA-name.

module: ietf-connection-oriented-oam +--rw domains +--rw domain* [technology md-name-string] . . +--rw mas +--rw ma* [ma-name-string] +--rw ma-name-string ma-name-string +--rw ma-name-format? identityref +--rw (ma-name)? | +--:(ma-name-null) | +--rw ma-name-null? empty

Within a given Maintenance Association (MA), there can be one or more Maintenance End Points (MEP). MEPs are represented as a list within the data hierarchy and indexed by the key MEP-name.

The RPC model facilitates issuing commands to a NETCONF server (in this case to the device that need to execute the OAM command) and obtain a response. RPC model defined here abstracts OAM specific commands in a technology independent manner. There are several RPC commands defined for the purpose of OAM. In this section we present a snippet of the continuity check command for illustration purposes. Please refer to Section 4.5 for the complete data hierarchy and Section 5 for the YANG model.

module: ietf-connection-oriented-oam +--rw domains +--rw domain* [technology MD-name-string] +--rw technology identityref . . rpcs: +---x continuity-check {continuity-check}? | +---w input | | +---w technology? identityref | | +---w md-name-string -> /domains/domain/md-name-string | | +---w md-level? -> /domains/domain/md-level | | +---w ma-name-string -> /domains/domain/mas/ma/ma-name-string | | +---w cos-id? uint8 | | +---w ttl? uint8 | | +---w sub-type? identityref | | +---w source-mep? -> /domains/domain/mas/ma/mep/mep-name | | +---w destination-mep | | | +---w (mep-address)? | | | | +--:(mac-address) | | | | | +---w mac-address? yang:mac-address | | | | +--:(ipv4-address) | | | | | +---w ipv4-address? inet:ipv4-address | | | | +--:(ipv6-address) | | | | +---w ipv6-address? inet:ipv6-address | | | +---w (mep-id)? | | | | +--:(mep-id-int) | | | | +---w mep-id-int? int32 | | | +---w mep-id-format? identityref | | +---w count? uint32 | | +---w cc-transmit-interval? interval | | +---w packet-size? uint32 | +--ro output | +--ro (monitor-stats)? | +--:(monitor-null) | +--ro monitor-null? empty +---x continuity-verification {connectivity-verification}? | +---w input | | +---w md-name-string -> /domains/domain/md-name-string | | +---w md-level? -> /domains/domain/md-level | | +---w ma-name-string -> /domains/domain/mas/ma/ma-name-string | | +---w cos-id? uint8 | | +---w ttl? uint8 | | +---w sub-type? identityref | | +---w source-mep? -> /domains/domain/mas/ma/mep/mep-name | | +---w destination-mep | | | +---w (mep-address)? | | | | +--:(mac-address) | | | | | +---w mac-address? yang:mac-address | | | | +--:(ipv4-address) | | | | | +---w ipv4-address? inet:ipv4-address | | | | +--:(ipv6-address) | | | | +---w ipv6-address? inet:ipv6-address | | | +---w (mep-id)? | | | | +--:(mep-id-int) | | | | +---w mep-id-int? int32 | | | +---w mep-id-format? identityref | | +---w count? uint32 | | +---w interval? interval | | +---w packet-size? uint32 | +--ro output | +--ro (monitor-stats)? | +--:(monitor-null) | +--ro monitor-null? empty +---x traceroute {traceroute}? +---w input | +---w md-name-string -> /domains/domain/md-name-string | +---w md-level? -> /domains/domain/md-level | +---w ma-name-string -> /domains/domain/mas/ma/ma-name-string | +---w cos-id? uint8 | +---w ttl? uint8 | +---w command-sub-type? identityref | +---w source-mep? -> /domains/domain/mas/ma/mep/mep-name | +---w destination-mep | | +---w (mep-address)? | | | +--:(mac-address) | | | | +---w mac-address? yang:mac-address | | | +--:(ipv4-address) | | | | +---w ipv4-address? inet:ipv4-address | | | +--:(ipv6-address) | | | +---w ipv6-address? inet:ipv6-address | | +---w (mep-id)? | | | +--:(mep-id-int) | | | +---w mep-id-int? int32 | | +---w mep-id-format? identityref | +---w count? uint32 | +---w interval? interval +--ro output +--ro response* [response-index] +--ro response-index uint8 +--ro ttl? uint8 +--ro destination-mep | +--ro (mep-address)? | | +--:(mac-address) | | | +--ro mac-address? yang:mac-address | | +--:(ipv4-address) | | | +--ro ipv4-address? inet:ipv4-address | | +--:(ipv6-address) | | +--ro ipv6-address? inet:ipv6-address | +--ro (mep-id)? | | +--:(mep-id-int) | | +--ro mep-id-int? int32 | +--ro mep-id-format? identityref +--ro mip {mip}? | +--ro interface? if:interface-ref | +--ro (mip-address)? | +--:(mac-address) | | +--ro mac-address? yang:mac-address | +--:(ipv4-address) | | +--ro ipv4-address? inet:ipv4-address | +--:(ipv6-address) | +--ro ipv6-address? inet:ipv6-address +--ro (monitor-stats)? +--:(monitor-null) +--ro monitor-null? empty

Notification is sent on defect condition and defect clears with Maintenance Domain Name, MA Name, defect-type (The currently active defects), generating-mepid, and defect-message to indicate more details.

Grouping for monitoring statistics is to be used by Yang modules which Augment Yang to provide statistics due to pro-active OAM like CCM Messages. For example CCM Transmit, CCM Receive, CCM Errors, etc.

The complete data hierarchy related to the connection oriented OAM YANG model is presented below.

module: ietf-connection-oriented-oam +--rw domains +--rw domain* [technology md-name-string] +--rw technology identityref +--rw md-name-string md-name-string +--rw md-name-format? identityref +--rw (md-name)? | +--:(md-name-null) | +--rw md-name-null? empty +--rw md-level? md-level +--rw mas +--rw ma* [ma-name-string] +--rw ma-name-string ma-name-string +--rw ma-name-format? identityref +--rw (ma-name)? | +--:(ma-name-null) | +--rw ma-name-null? empty +--rw (connectivity-context)? | +--:(context-null) | +--rw context-null? empty +--rw cos-id? uint8 +--rw cc-enable? boolean +--rw mep* [mep-name] | +--rw mep-name mep-name | +--rw (mep-id)? | | +--:(mep-id-int) | | +--rw mep-id-int? int32 | +--rw mep-id-format? identityref | +--rw (mep-address)? | | +--:(mac-address) | | | +--rw mac-address? yang:mac-address | | +--:(ipv4-address) | | | +--rw ipv4-address? inet:ipv4-address | | +--:(ipv6-address) | | +--rw ipv6-address? inet:ipv6-address | +--rw cos-id? uint8 | +--rw cc-enable? boolean | +--rw session* [session-cookie] | +--rw session-cookie uint32 | +--rw destination-mep | | +--rw (mep-id)? | | | +--:(mep-id-int) | | | +--rw mep-id-int? int32 | | +--rw mep-id-format? identityref | +--rw destination-mep-address | | +--rw (mep-address)? | | +--:(mac-address) | | | +--rw mac-address? yang:mac-address | | +--:(ipv4-address) | | | +--rw ipv4-address? inet:ipv4-address | | +--:(ipv6-address) | | +--rw ipv6-address? inet:ipv6-address | +--rw cos-id? uint8 +--rw mip* [interface] {mip}? +--rw interface if:interface-ref +--rw (mip-address)? +--:(mac-address) | +--rw mac-address? yang:mac-address +--:(ipv4-address) | +--rw ipv4-address? inet:ipv4-address +--:(ipv6-address) +--rw ipv6-address? inet:ipv6-address rpcs: +---x continuity-check {continuity-check}? | +---w input | | +---w technology? identityref | | +---w md-name-string -> /domains/domain/md-name-string | | +---w md-level? -> /domains/domain/md-level | | +---w ma-name-string -> /domains/domain/mas/ma/ma-name-string | | +---w cos-id? uint8 | | +---w ttl? uint8 | | +---w sub-type? identityref | | +---w source-mep? -> /domains/domain/mas/ma/mep/mep-name | | +---w destination-mep | | | +---w (mep-address)? | | | | +--:(mac-address) | | | | | +---w mac-address? yang:mac-address | | | | +--:(ipv4-address) | | | | | +---w ipv4-address? inet:ipv4-address | | | | +--:(ipv6-address) | | | | +---w ipv6-address? inet:ipv6-address | | | +---w (mep-id)? | | | | +--:(mep-id-int) | | | | +---w mep-id-int? int32 | | | +---w mep-id-format? identityref | | +---w count? uint32 | | +---w cc-transmit-interval? interval | | +---w packet-size? uint32 | +--ro output | +--ro (monitor-stats)? | +--:(monitor-null) | +--ro monitor-null? empty +---x continuity-verification {connectivity-verification}? | +---w input | | +---w md-name-string -> /domains/domain/md-name-string | | +---w md-level? -> /domains/domain/md-level | | +---w ma-name-string -> /domains/domain/mas/ma/ma-name-string | | +---w cos-id? uint8 | | +---w ttl? uint8 | | +---w sub-type? identityref | | +---w source-mep? -> /domains/domain/mas/ma/mep/mep-name | | +---w destination-mep | | | +---w (mep-address)? | | | | +--:(mac-address) | | | | | +---w mac-address? yang:mac-address | | | | +--:(ipv4-address) | | | | | +---w ipv4-address? inet:ipv4-address | | | | +--:(ipv6-address) | | | | +---w ipv6-address? inet:ipv6-address | | | +---w (mep-id)? | | | | +--:(mep-id-int) | | | | +---w mep-id-int? int32 | | | +---w mep-id-format? identityref | | +---w count? uint32 | | +---w interval? interval | | +---w packet-size? uint32 | +--ro output | +--ro (monitor-stats)? | +--:(monitor-null) | +--ro monitor-null? empty +---x traceroute {traceroute}? +---w input | +---w md-name-string -> /domains/domain/md-name-string | +---w md-level? -> /domains/domain/md-level | +---w ma-name-string -> /domains/domain/mas/ma/ma-name-string | +---w cos-id? uint8 | +---w ttl? uint8 | +---w command-sub-type? identityref | +---w source-mep? -> /domains/domain/mas/ma/mep/mep-name | +---w destination-mep | | +---w (mep-address)? | | | +--:(mac-address) | | | | +---w mac-address? yang:mac-address | | | +--:(ipv4-address) | | | | +---w ipv4-address? inet:ipv4-address | | | +--:(ipv6-address) | | | +---w ipv6-address? inet:ipv6-address | | +---w (mep-id)? | | | +--:(mep-id-int) | | | +---w mep-id-int? int32 | | +---w mep-id-format? identityref | +---w count? uint32 | +---w interval? interval +--ro output +--ro response* [response-index] +--ro response-index uint8 +--ro ttl? uint8 +--ro destination-mep | +--ro (mep-address)? | | +--:(mac-address) | | | +--ro mac-address? yang:mac-address | | +--:(ipv4-address) | | | +--ro ipv4-address? inet:ipv4-address | | +--:(ipv6-address) | | +--ro ipv6-address? inet:ipv6-address | +--ro (mep-id)? | | +--:(mep-id-int) | | +--ro mep-id-int? int32 | +--ro mep-id-format? identityref +--ro mip {mip}? | +--ro interface? if:interface-ref | +--ro (mip-address)? | +--:(mac-address) | | +--ro mac-address? yang:mac-address | +--:(ipv4-address) | | +--ro ipv4-address? inet:ipv4-address | +--:(ipv6-address) | +--ro ipv6-address? inet:ipv6-address +--ro (monitor-stats)? +--:(monitor-null) +--ro monitor-null? empty notifications: +---n defect-condition-notification | +--ro technology? identityref | +--ro md-name-string -> /domains/domain/md-name-string | +--ro ma-name-string -> /domains/domain/mas/ma/ma-name-string | +--ro mep-name? -> /domains/domain/mas/ma/mep/mep-name | +--ro defect-type? identityref | +--ro generating-mepid | | +--ro (mep-id)? | | | +--:(mep-id-int) | | | +--ro mep-id-int? int32 | | +--ro mep-id-format? identityref | +--ro (defect)? | +--:(defect-null) | | +--ro defect-null? empty | +--:(defect-code) | +--ro defect-code? int32 +---n defect-cleared-notification +--ro technology? identityref +--ro md-name-string -> /domains/domain/md-name-string +--ro ma-name-string -> /domains/domain/mas/ma/ma-name-string +--ro mep-name? -> /domains/domain/mas/ma/mep/mep-name +--ro defect-type? identityref +--ro generating-mepid | +--ro (mep-id)? | | +--:(mep-id-int) | | +--ro mep-id-int? int32 | +--ro mep-id-format? identityref +--ro (defect)? +--:(defect-null) | +--ro defect-null? empty +--:(defect-code) +--ro defect-code? int32

<CODE BEGINS> file "ietf-connection-oriented-oam@2017-06-01.yang"

module ietf-connection-oriented-oam { namespace "urn:ietf:params:xml:ns:yang:ietf-connection-oriented-oam"; prefix goam; import ietf-yang-types { prefix yang; } import ietf-inet-types { prefix inet; } import ietf-interfaces { prefix if; } organization "IETF LIME Working Group"; contact "WG Web: http://tools.ietf.org/wg/lime WG List: mailto:lime@ietf.org WG Chair: Carlos Pignataro cpignata@cisco.com WG Chair: Ron Bonica rbonica@juniper.net Editor: Deepak Kumar dekumar@cisco.com Editor: Qin Wu bill.wu@huawei.com Editor: Zitao Wang wangzitao@huawei.com"; description "This YANG module defines the generic configuration, statistics and rpc for connection oriented OAM to be used within IETF in a protocol indpendent manner. Functional level abstraction is indendent with YANG modeling. It is assumed that each protocol maps corresponding abstracts to its native format. Each protocol may extend the YANG model defined here to include protocol specific extensions"; revision 2017-06-01 { description "Initial revision. - 09 version"; reference "draft-ietf-lime-yang-oam-model"; } /* features */ feature connectivity-verification { description "This feature indicates that the server supports executing connectivity verification OAM command and returning a response. Servers that do not advertise this feature will not support executing connectivity verification command or rpc model for connectivity verification command."; } feature continuity-check{ description "This feature indicates that the server supports executing continuity check OAM command and returning a response. Servers that do not advertise this feature will not support executing continuity check command or rpc model for continuity check command."; } feature traceroute{ description "This feature indicates that the server supports executing traceroute OAM command and returning a response. Servers that do not advertise this feature will not support executing traceroute command or rpc model for traceroute command."; } feature mip { description "This feature indicates that the Maintenance Intermediate Point(MIP) needs to be explicit configured"; } /* Identities */ identity technology-types { description "This is the base identy of technology types which are TRILL,MPLS-TP,vpls etc"; } identity command-sub-type { description "Defines different rpc command subtypes, e.g rfc6905 trill OAM, this is optional for most cases"; } identity on-demand { base command-sub-type; description "On demand activation - indicates that the tool is activated manually to detect a specific anomaly. On-demand OAM method requires only transient configuration."; } identity proactive { base command-sub-type; description "Proactive activation - indicates that the tool is activated on a continual basis, where messages are sent periodically, and errors are detected when a certain number of expected messages are not received. Proactive OAM method requires persistent configuration."; } identity name-format { description "This defines the name format, IEEE 8021ag CFM defines varying styles of names. It is expected name format as an identity ref to be extended with new types."; } identity name-format-null { base name-format; description "Defines name format as null"; } identity identifier-format { description "Identifier-format identity can be augmented to define other format identifiers used in MEP-ID etc"; } identity identifier-format-integer { base identifier-format; description "Defines identifier-format to be integer"; } identity defect-types { description "Defines different defect types, e.g. Remote Defect Indication (rdi), loss of continuity"; } identity rdi { base defect-types; description "Indicates the aggregate health of the remote Maintenance End Points (MEPs). "; } identity remote-mep-defect{ base defect-types; description "Indicates that one or more of the remote Maintenance End Points(MEPs)is reporting a failure "; } identity loss-of-continuity{ base defect-types; description "If no proactive Continuity Check (CC) OAM packets from the source Maintenance End Point (MEP) (and in the case of Connectivity Verification , this includes the requirement to have the expected unique, technology dependent source MEP identifier) are received within the interval."; } identity cv-defect { base defect-types; description "This function should support monitoring between the Maintenance End Points (MEPs) and, in addition, between a MEP and Maintenance Intermediate Point (MIP). [RFC6371] highlights,when performing Connectivity Verification, the need for the Continuity Check and Connectivity Verification (CC-V) messages to include unique identification of the MEG that is being monitored and the MEP that originated the message."; } identity invalid-oam-defect{ base defect-types; description "Indicates that one or more invalid OAM messages has been received and that 3.5 times that OAM message transmission interval has not yet expired."; } identity cross-connect-defect{ base defect-types; description "Indicates that one or more cross-connect defect (for example, a service ID does not match the VLAN.) messages has been received and that 3.5 times that OAM message transmission interval has not yet expired."; } /* typedefs */ typedef mep-name { type string; description "Generic administrative name for a Maintenance End Point (MEP)."; } typedef interval{ type decimal64{ fraction-digits 2; } units "milliseconds"; description "Interval between packets in milliseconds. 0 means no packets are sent."; } typedef md-name-string { type string; description "Generic administrative name for Maintenance Domain (MD)."; } typedef ma-name-string { type string; description "Generic administrative name for an Maintenance Association (MA)."; } typedef oam-counter32 { type yang:zero-based-counter32; description "Define 32 bit counter for OAM."; } typedef md-level { type uint32 { range "0..255"; } description "Maintenance Domain level. The level may be restricted in certain protocols (e.g., protocol in layer 0 to layer 7)."; } /* groupings */ grouping maintenance-domain-reference { description "This grouping uniquely identifies a maintenance domain."; leaf maintenance-domain { type leafref { path "/goam:domains/goam:domain/goam:md-name-string"; } description "A reference to a specific Maintenance Domain."; } } grouping maintenance-association-reference { description "This grouping uniquely identifies a maintenance association. It consists of a maintence-domain-reference and a maintenance-association leafref"; uses maintenance-domain-reference; leaf maintenance-association { type leafref { path "/goam:domains/goam:domain" +"[goam:md-name-string = current()/" +"../maintenance-domain]/goam:mas" +"/goam:ma/goam:ma-name-string"; } description "A reference to a specific Maintenance Association."; } } grouping maintenance-association-end-point-reference { description "This grouping uniquely identifies a maintenance association. It consists of a maintence-association-reference and a maintenance-association-end-point leafref"; uses maintenance-association-reference; leaf maintenance-association-end-point { type leafref { path "/goam:domains/goam:domain" +"[goam:md-name-string = current()/" +"../maintenance-domain]/goam:mas" +"/goam:ma[goam:ma-name-string = " +"current()/../maintenance-association]" +"/goam:mep/goam:mep-name"; } description "A reference to a specific Maintenance association End Point."; } } grouping time-to-live { leaf ttl{ type uint8; description "Time to Live."; } description "Time to Live grouping."; } grouping defect-message { choice defect { case defect-null { description "This is a placeholder when no defect status is needed"; leaf defect-null { type empty; description "There is no defect to be defined, it will be defined in technology specific model."; } } case defect-code { description "This is a placeholder to display defect code."; leaf defect-code { type int32; description "Defect code is integer value specific to a technology."; } } description "Defect Message choices."; } description "Defect Message."; } grouping mep-address { choice mep-address { case mac-address { leaf mac-address { type yang:mac-address; description "MAC Address"; } description "MAC Address based Maintenance End Point (MEP) Addressing."; } case ipv4-address { leaf ipv4-address { type inet:ipv4-address; description "IPv4 Address"; } description "IP Address based Maintenance End Point(MEP) Addressing."; } case ipv6-address { leaf ipv6-address { type inet:ipv6-address; description "IPv6 Address"; } description "IPv6 Address based Maintenance End Point(MEP) Addressing."; } description "Maintenance End Point (MEP) Addressing."; } description "Maintenance End Point(MEP) Address"; } grouping mip-address { choice mip-address { case mac-address { leaf mac-address { type yang:mac-address; description "MAC Address"; } description "MAC Address based Maintenance Intermediate Point (MIP) Addressing."; } case ipv4-address { leaf ipv4-address { type inet:ipv4-address; description "IPv4 Address."; } description "IP Address based Maintenance Intermediate Point (MIP) Addressing."; } case ipv6-address { leaf ipv6-address { type inet:ipv6-address; description "IPv6 Address."; } description "IPv6 Address based Maintenance Intermediate Point (MIP) Addressing."; } description "Maintenance Intermediate Point (MIP) Addressing."; } description "Maintenance Intermediate Point (MIP) Address."; } grouping maintenance-domain-id { description "Grouping containing leaves sufficient to identify a Maintenance Domain."; leaf technology { type identityref { base technology-types; } mandatory true; description "Defines the technology."; } leaf md-name-string { type md-name-string; mandatory true; description "Defines the generic administrative maintenance domain name."; } } grouping md-name { leaf md-name-format { type identityref { base name-format; } description "Name format."; } choice md-name { case md-name-null { leaf md-name-null { when "'../../../md-name-format' = 'name-format-null'" { description "Maintenance Domain (MD) name format is equal to null format."; } type empty; description "Maintenance Domain (MD) name Null."; } } description "Maintenance Domain (MD) name."; } description "Maintenance Domain (MD) name."; } grouping ma-identifier { description "Grouping containing leaves sufficient to identify an Maintenance Association (MA)."; leaf ma-name-string { type ma-name-string; description "Maintenance Association (MA) name string."; } } grouping ma-name { description "Maintenance Association (MA) name."; leaf ma-name-format { type identityref { base name-format; } description "Maintenance Association (MA) name format."; } choice ma-name { case ma-name-null { leaf ma-name-null { when "'../../../ma-name-format' = 'name-format-null'" { description "Maintenance Association (MA)."; } type empty; description "Empty"; } } description "Maintenance Association) name(MA)."; } } grouping mep-id { choice mep-id { default "mep-id-int"; case mep-id-int { leaf mep-id-int { type int32; description "Maintenance End Point (MEP) ID in integer format."; } } description "Maintenance End Point (MEP) ID."; } leaf mep-id-format { type identityref { base identifier-format; } description "Maintenance End Point (MEP) ID format."; } description "Maintenance End Point (MEP) ID."; } grouping mep { description "Defines elements within the Maintenance End Point (MEP)."; leaf mep-name { type mep-name; mandatory true; description "Generic administrative name of the Maintenance End Point (MEP)."; } uses mep-id; uses mep-address; } grouping monitor-stats { description "grouping for monitoring statistics, this will be augmented by others who use this component"; choice monitor-stats { default "monitor-null"; case monitor-null { description "This is a place holder when no monitoring statistics is needed"; leaf monitor-null { type empty; description "There is no monitoring statistics to be defined."; } } description "Define the monitor stats."; } } grouping connectivity-context { description "Grouping defining the connectivity context for an Maintenance Association (MA), for example, a VRF for VPLS, or an LSP for MPLS-TP. This will be augmented by each protocol who use this component."; choice connectivity-context { default "context-null"; case context-null { description "This is a place holder when no context is needed."; leaf context-null { type empty; description "There is no context to be defined."; } } description "Connectivity context."; } } grouping cos { description "Priority used in transmitted packets; for example, in the EXP field in MPLS-TP."; leaf cos-id { type uint8; description "Class of service."; } } grouping mip-grouping { uses mip-address; description "Grouping for Maintenance Intermediate Point(MIP) configuration."; } container domains { description "Contains configuration related data. Within the container is list of fault domains. Within each domian has List of Maintenance Association (MA)."; list domain { key "technology md-name-string"; description "Define the list of fault Domains within the ietf-connection-oriented-oam module."; uses maintenance-domain-id; uses md-name; leaf md-level { type md-level; description "Define the MD-Level."; } container mas { description "This container defines Maintenance Association (MA), within that have multiple MA and within MA have Maintenance End Point (MEP)."; list ma { key "ma-name-string"; uses ma-identifier; uses ma-name; uses connectivity-context; uses cos { description "Default class of service for this Maintenance Association (MA), which may be overridden for particular Maintenance End Points (MEPs), sessions or operations."; } leaf cc-enable{ type boolean; description "Indicate whether the Continuity Check (CC) is enabled."; } list mep { key "mep-name"; description "Contain a list of Maintenance End Points (MEPs)"; uses mep; uses cos; leaf cc-enable{ type boolean; description "Indicate whether the Continuity Check (CC)is enabled."; } list session { key "session-cookie"; ordered-by user; description "Monitoring session to/from a particular remote Maintenance End Point (MEP). Depending on the protocol, this could represent Continuity Check (CC) messages received from a single remote MEP (if the protocol uses multicast CCs) or a target to which unicast echo request CCs are sent and from which responses are received (if the protocol uses a unicast request/response mechanism)."; leaf session-cookie { type uint32; description "Cookie to identify different sessions, when there are multiple remote Maintenance End Point(MEP) or multiple sessions tothe same remote MEP."; } container destination-mep { uses mep-id; description "Destination Maintenance End Point(MEP)."; } container destination-mep-address { uses mep-address; description "Destination Maintenance End Point (MEP) Address."; } uses cos; } } list mip { if-feature mip; key "interface"; leaf interface { type if:interface-ref; description "Interface"; } uses mip-grouping; description "List for Maintenance Intermediate Point (MIP)."; } description "Maintenance Association list."; } } } } notification defect-condition-notification { description "Upon the defect condition is met, this notification is sent"; leaf technology { type identityref { base technology-types; } description "The technology"; } leaf md-name-string { type leafref{ path "/domains/domain/md-name-string"; } mandatory true; description "Indicate which Maintenance Domain(MD) does the defect belong to."; } leaf ma-name-string{ type leafref{ path "/domains/domain/mas/ma/ma-name-string"; } mandatory true; description "Indicate which Maintenance Association (MA) is the defect associated with."; } leaf mep-name { type leafref{ path "/domains/domain/mas/ma/mep/mep-name"; } description "Indicate which Maintenance End Point(MEP) is seeing the defect."; } leaf defect-type { type identityref { base defect-types; } description "The currently active defects on the specific Maintenance End Point (MEP)."; } container generating-mepid { uses mep-id; description "Indicate who is generating the defect (if known). If unknown set it as 0."; } uses defect-message { description "The defect message to indicate more details."; } } notification defect-cleared-notification { description "Upon defect cleared is met, this notification is sent"; leaf technology { type identityref { base technology-types; } description "The technology."; } leaf md-name-string { type leafref{ path "/domains/domain/md-name-string"; } mandatory true; description "Indicate which Maintenance Domain (MD) does the defect belong to"; } leaf ma-name-string{ type leafref{ path "/domains/domain/mas/ma/ma-name-string"; } mandatory true; description "Indicate which Maintenance Association (MA) is the defect associated with."; } leaf mep-name { type leafref{ path "/domains/domain/mas/ma/mep/mep-name"; } description "Indicate which Maintenance End Point (MEP) is seeing the defect."; } leaf defect-type { type identityref { base defect-types; } description "The currently active defects on the specific Maintenance End Point (MEP)."; } container generating-mepid { uses mep-id; description "Indicate who is generating the defect (if known). if unknown set it as 0."; } uses defect-message { description "Defect message to indicate more details."; } } rpc continuity-check { if-feature "continuity-check"; description "Generates continuity-check as per RFC7276 Table 4."; input { leaf technology { type identityref { base technology-types; } description "The technology"; } leaf md-name-string { type leafref{ path "/domains/domain/md-name-string"; } mandatory true; description "Indicate which Maintenance Domain (MD) does the defect belong to."; } leaf md-level { type leafref { path "/domains/domain/md-level"; } description "The maintenance domain level."; } leaf ma-name-string{ type leafref{ path "/domains/domain/mas/ma/ma-name-string"; } mandatory true; description "Indicate which MA is the defect associated with"; } uses cos; uses time-to-live; leaf sub-type { type identityref { base command-sub-type; } description "Defines different command types."; } leaf source-mep { type leafref{ path "/domains/domain/mas/ma/mep/mep-name"; } description "Source Maintenance End Point (MEP)."; } container destination-mep { uses mep-address; uses mep-id { description "Only applicable if the destination is a Maintenance End Point (MEP)."; } description "Destination Maintenance End Point (MEP)."; } leaf count { type uint32; default "3"; description "Number of continuity-check message to be sent."; } leaf cc-transmit-interval { type interval; description "Interval between echo requests."; } leaf packet-size { type uint32 { range "0..10000"; } default "64"; description "Size of continuity-check packets, in octets."; } } output { uses monitor-stats { description "Stats of continuity check."; } } } rpc continuity-verification { if-feature connectivity-verification; description "Generates continuity-verification as per RFC7276 Table 4."; input { leaf md-name-string { type leafref{ path "/domains/domain/md-name-string"; } mandatory true; description "Indicate which MD (Maintenance Domain) does the defect belong to."; } leaf md-level { type leafref { path "/domains/domain/md-level"; } description "The maintenance domain level."; } leaf ma-name-string{ type leafref{ path "/domains/domain/mas/ma/ma-name-string"; } mandatory true; description "Indicate which Maintenance Association (MA) is the defect associated with."; } uses cos; uses time-to-live; leaf sub-type { type identityref { base command-sub-type; } description "Defines different command types."; } leaf source-mep { type leafref{ path "/domains/domain/mas/ma/mep/mep-name"; } description "Source Maintenance End Point(MEP)."; } container destination-mep { uses mep-address; uses mep-id { description "Only applicable if the destination is a Maintenance End Point (MEP)."; } description "Destination Maintenance End Point(MEP)."; } leaf count { type uint32; default "3"; description "Number of continuity-verification message to be sent."; } leaf interval { type interval; description "Interval between echo requests."; } leaf packet-size { type uint32 { range "64..10000"; } default "64"; description "Size of continuity-verification packets, in octets"; } } output { uses monitor-stats { description "Stats of continuity check."; } } } rpc traceroute { if-feature traceroute; description "Generates Traceroute or Path Trace and return response. Referencing RFC7276 for common Toolset name, for MPLS-TP OAM it's Route Tracing, and for TRILL OAM It's Path Tracing tool. Starts with TTL of one and increment by one at each hop. Untill destination reached or TTL reach max value."; input { leaf md-name-string { type leafref{ path "/domains/domain/md-name-string"; } mandatory true; description "Indicate which Maintenance Domain (MD) does the defect belong to."; } leaf md-level { type leafref { path "/domains/domain/md-level"; } description "The maintenance domain level."; } leaf ma-name-string{ type leafref{ path "/domains/domain/mas/ma/ma-name-string"; } mandatory true; description "Indicate which Maintenance Association (MA) is the defect associated with."; } uses cos; uses time-to-live; leaf command-sub-type { type identityref { base command-sub-type; } description "Defines different command types."; } leaf source-mep { type leafref{ path "/domains/domain/mas/ma/mep/mep-name"; } description "Source Maintenance End Point (MEP)."; } container destination-mep { uses mep-address; uses mep-id { description "Only applicable if the destination is a Maintenance End Point (MEP)."; } description "Destination Maintenance End Point (MEP)."; } leaf count { type uint32; default "1"; description "Number of traceroute probes to send. In protocols where a separate message is sent at each TTL, this is the number of packets to be sent at each TTL."; } leaf interval { type interval; description "Interval between echo requests."; } } output { list response { key "response-index"; leaf response-index { type uint8; description "Arbitrary index for the response. In protocols that guarantee there is only a single response at each TTL, the TTL can be used as the response index."; } uses time-to-live; container destination-mep { description "Maintenance End Point (MEP) from which the response has been received"; uses mep-address; uses mep-id { description "Only applicable if the destination is a Maintenance End Point (MEP)."; } } container mip { if-feature mip; leaf interface { type if:interface-ref; description "Maintenance Intermediate Point (MIP) interface."; } uses mip-address; description "Maintenance Intermediate Point (MIP) responding with traceroute"; } uses monitor-stats { description "Stats of traceroute."; } description "List of response."; } } } } <CODE ENDS>

The Base Mode ('default mode' described in section 4) defines default configuration that MUST be present in the devices that comply with this document. Base Mode allows users to have "zero-touch" experience. Several parameters require technology specific definition.

In the Base Mode of operation, the MEP Address is by default the IP address of the interface on which the MEP is located.

In the Base Mode of operation, each device creates a single MEP associated with a virtual OAM port with no physical layer (NULL PHY). The MEP-ID associated with this MEP is zero (0). The choice of MEP-ID zero is explained below. MEP-ID is 2 octet field by default. It is never used on the wire except when using CCM. It is important to have method that can derive MEP-ID of base mode in an automatic manner with no user intervention. IP address cannot be directly used for this purpose as the MEP-ID is much smaller field. For Base Mode of operation we propose to use MEP-ID zero (0) as the default MEP-ID. CCM packet use MEP-ID on the payload. CCM MUST NOT be used in the Base Mode. Hence CCM MUST be disabled on the Maintenance Association of the Base Mode. If CCM is required, users MUST configure a separate Maintenance association and assign unique value for the corresponding MEP IDs. CFM defines MEP ID as an unsigned integer in the range 1 to 8191. In this document we propose extend the range to 0 to 65535. Value 0 is reserved for MEP-ID of Base Mode operation and MUST NOT be used for other purposes.

The ID of the Maintenance Association (MA-ID) has a flexible format and includes two parts: Maintenance Domain Name and Short MA name. In the Based Mode of operation, the value of the Maintenance Domain Name must be the character string "GenericBaseMode" (excluding the quotes "). In Base Mode operation Short MA Name format is set to 2-octet integer format (value 3 in Short MA Format field ) and Short MA name set to 65532 (0xFFFC).

"ietf-connection-oriented-oam" model defined in this document provides technology-independent abstraction of key OAM constructs for connection oriented protocols. This model can be further extended to include technology specific details, e.g., adding new data nodes with technology specific functions and parameters into proper anchor points of the base model, so as to develop a technology-specific connection-oriented OAM model. This section demonstrates the usability of the connection-oriented YANG OAM data model to various connection-oriented OAM technologies, e.g., TRILL and MPLS-TP. Note that, in this section, we only present several snippets of technology-specific model extensions for illustrative purposes. The complete model extensions should be worked on in respective protocol working groups.

The TRILL YANG module is augmenting connection oriented OAM module for both configuration and RPC commands. The TRILL YANG module requires the base TRILL module ([I-D.ietf-trill-yang]) to be supported as there is a strong relationship between those modules. The configuration extensions for connection oriented OAM include MD configuration extension, Technology type extension, MA configuration extension, Connectivity-Context Extension, MEP Configuration Extension, ECMP extension. In the RPC extension, the continuity-check and path-discovery RPC are extended with TRILL specific.

MD level configuration parameters are management information which can be inherited in the TRILL OAM model and set by connection oriented base model as default values. For example domain name can be set to area-ID in the TRILL OAM case. In addition, at the Maintenance Domain level (i.e., at root level), domain data node can be augmented with technology type. Note that MD level configuration parameters provides context information for the management system to correlate faults, defects, network failures with location information, which helps quickly identify root causes of network failures.

No TRILL technology type has been defined in the connection oriented base model. Therefore a technology type extension is required in the TRILL OAM model. The technology type "trill" is defined as an identity that augments the base "technology-types" defined in the connection oriented base model:

identity trill{ base goam:technology-types; description "trill type"; }

MA level configuration parameters are management information which can be inherited in the TRILL OAM model and set by connection oriented base model as default values. In addition, at the Maintenance Association(MA) level (i.e.,at the second level), MA data node can be augmented with connectivity-context extension. Note that MA level configuration parameters provides context information for the management system to correlate faults, defects, network failures with location information, which helps quickly identify root causes of network failures.

In TRILL OAM, one example of connectivity-context is either a 12 bit VLAN ID or a 24 bit Fine Grain Label. The connection oriented base model defines a placeholder for context-id. This allows other technologies to easily augment that to include technology specific extensions. The snippet below depicts an example of augmenting connectivity-context to include either VLAN ID or Fine Grain Label.

augment /goam:domains/goam:domain /goam:mas/goam:ma/goam:connectivity-context: +--:(connectivity-context-vlan) | +--rw connectivity-context-vlan? vlan +--:(connectivity-context-fgl) +--rw connectivity-context-fgl? fgl

The MEP configuration definition in the connection oriented base model already supports configuring the interface of MEP with either MAC address or IP address. In addition, the MEP address can be represented using a 2 octet RBridge Nickname in TRILL OAM . Hence, the TRILL OAM model augments the MEP configuration in base model to add a nickname case into the MEP address choice node as follows:

augment /goam:domains/goam:domain /goam:mas/goam:ma/goam:mep/goam:mep-address: +--:( mep-address-trill) | +--rw mep-address-trill? tril-rb-nickname In addition, at the Maintenance Association Endpoint(MEP) level (i.e.,at the third level), MEP data node can be augmented with ECMP extension.

Since TRILL supports ECMP path selection, flow-entropy in TRILL is defined as a 96 octet field in the LIME model extension for TRILL OAM. The snippet below illustrates its extension.

augment /goam:domains/goam:domain /goam:mas/goam:ma/goam:mep: +--rw flow-entropy-trill? flow-entropy-trill augment /goam:domains/goam:domain /goam:mas/goam:ma/goam:mep/goam:session: +--rw flow-entropy-trill? flow-entropy-trill

In the TRILL OAM YANG model, the continuity-check and path-discovery RPC commands are extended with TRILL specific requirements. The snippet below depicts an example of illustrates the TRILL OAM RPC extension.

augment /goam:continuity-check/goam:input: +--ro (out-of-band)? | +--:(ipv4-address) | | +--ro ipv4-address? inet:ipv4-address | +--:(ipv6-address) | | +--ro ipv6-address? inet:ipv6-address | +--:(trill-nickname) | +--ro trill-nickname? tril-rb-nickname +--ro diagnostic-vlan? boolean augment /goam:continuity-check/goam:input: +--ro flow-entropy-trill? flow-entropy-trill augment /goam:continuity-check/goam:output: +--ro upstream-rbridge? tril-rb-nickname +--ro next-hop-rbridge* tril-rb-nickname augment /goam:path-discovery/goam:input: +--ro (out-of-band)? | +--:(ipv4-address) | | +--ro ipv4-address? inet:ipv4-address | +--:(ipv6-address) | | +--ro ipv6-address? inet:ipv6-address | +--:(trill-nickname) | +--ro trill-nickname? tril-rb-nickname +--ro diagnostic-vlan? boolean augment /goam:path-discovery/goam:input: +--ro flow-entropy-trill? flow-entropy-trill augment /goam:path-discovery/goam:output/goam:response: +--ro upstream-rbridge? tril-rb-nickname +--ro next-hop-rbridge* tril-rb-nickname

The MPLS-TP OAM YANG module can augment connection oriented OAM Module with some technology-specific details. And the presents the YANG Data model for MPLS-TP OAM. The configuration extensions for connection oriented OAM include MD configuration extension, Technology type extension, Sub Technology Type Extension ,MA configuration extension, MEP Configuration Extension.

MD level configuration parameters are management information which can be inherited in the MPLS-TP OAM model and set by LIME base model as default values. For example domain name can be set to area-ID or the provider's Autonomous System Number(ASN) in the MPLS-TP OAM case. In addition, at the Maintenance Domain level (i.e.,at root level), domain data node can be augmented with technology type and sub-technology type. Note that MD level configuration parameters provides context information for the management system to correlate faults, defects, network failures with location information, which helps quickly identify root causes of network failures

No MPLS-TP technology type has been defined in the connection oriented base model, hence it is required in the MPLS-TP OAM model. The technology type "mpls-tp" is defined as an identity that augments the base "technology-types" defined in the connection oriented base model:

identity mpls-tp{ base goam:technology-types; description "mpls-tp type"; }

In MPLS-TP, since different encapsulation types such as IP/UDP Encapsulation, PW-ACH encapsulation can be employed, the "technology- sub-type" data node is defined and added into the MPLS-TP OAM model to further identify the encapsulation types within the MPLS-TP OAM model. Based on it, we also define a technology sub-type for IP/UDP encapsulation and PW-ACH encapsulation. Other Encapsulation types can be defined in the same way. The snippet below depicts an example of several encapsulation types.

identity technology-sub-type { description "certain implementations can have different encapsulation types such as ip/udp, pw-ach and so on. Instead of defining separate models for each encapsulation, we define a technology sub-type to further identify different encapsulations. Technology sub-type is associated at the MA level"; } identity technology-sub-type-udp { base technology-sub-type; description "technology sub-type is IP/UDP encapsulation"; } identity technology-sub-type-ach { base technology-sub-type; description "technology sub-type is PW-ACH encapsulation"; } } augment "/goam:domains/goam:domain" +"/goam:mas/goam:ma { leaf technology-sub-type { type identityref { base technology-sub-type; } } }

MA level configuration parameters are management information which can be inherited in the MPLS-TP OAM model and set by Connection Oriented base model as default values. One example of MA Name could be MEG LSP ID or MEG Section ID or MEG PW ID[RFC6370]. Note that MA level configuration parameters provides context information for the management system to correlate faults, defects, network failures with location information, which helps quickly identify root causes of network failures.

In MPLS-TP, MEP-ID is either a variable length label value in case of G-ACH encapsulation or a 2 octet unsigned integer value in case of IP/UDP encapsulation. One example of MEP-ID is MPLS-TP LSP_MEP_ID [RFC6370]. In the connection-oriented base model, MEP-ID is defined as a choice/case node which can supports an int32 value, and the same definition can be used for MPLS-TP with no further modification. In addition, at the Maintenance Association Endpoint(MEP) level (i.e.,at the third level), MEP data node can be augmented with Session extension and interface extension.

The YANG module defined in this memo is designed to be accessed via the NETCONF protocol [RFC6241] . The lowest NETCONF layer is the secure transport layer and the mandatory-to-implement secure transport is SSH [RFC6242] . The NETCONF access control model [RFC6536] provides the means to restrict access for particular NETCONF users to a pre-configured subset of all available NETCONF protocol operations and content. There are a number of data nodes defined in the YANG module which are writable/creatable/deletable (i.e., config true, which is the default). These data nodes may be considered sensitive or vulnerable in some network environments. Write operations (e.g., <edit-config>) to these data nodes without proper protection can have a negative effect on network operations. The vulnerable "config true" subtrees and data nodes are the following:

/goam:domains/goam:domain/ /goam:domains/goam:domain/goam:mas/goam:ma /goam:domains/goam:domain/goam:mas/goam:ma/goam:mep /goam:domains/goam:domain/goam:mas/goam:ma/goam:mep/goam:session/ Unauthorized access to any of these lists can adversely affect OAM management system handling of end-to-end OAM and coordination of OAM within underlying network layers This may lead to inconsistent configuration, reporting, and presentation for the OAM mechanisms used to manage the network.

This document registers a URI in the IETF XML registry [RFC3688]. Following the format in RFC 3688, the following registration is requested to be made:

URI: urn:ietf:params:xml:ns:yang:ietf-gen-oam Registrant Contact: The IESG. XML: N/A, the requested URI is an XML namespace. This document registers a YANG module in the YANG Module Names registry .

name: ietf-gen-oam namespace: urn:ietf:params:xml:ns:yang:ietf-gen-oam prefix: goam reference: RFC XXXX

Giles Heron came up with the idea of developing a YANG model as a way of creating a unified OAM API set (interface), work in this document is largely an inspiration of that. Alexander Clemm provided many valuable tips, comments and remarks that helped to refine the YANG model presented in this document. Carlos Pignataro, David Ball,Mahesh Jethanandani,Benoit Claise,Ladislav Lhotka,GUBALLA JENS,Yuji Tochio,Gregory Mirsky, Huub van Helvoort, Tom Taylor, Dapeng Liu,Mishael Wexler, Adi Molkho participated and contributed to this document.

Connectivity Fault Management OAM functions and mechanisms for Ethernet based networks YANG Data Model for MPLS-TP Operations, Administration, and Maintenance

Tissa Senevirathne Consultant Email: tsenevir@gmail.com Norman Finn CISCO Systems 510 McCarthy Blvd Milpitas, CA 95035 USA Email: nfinn@cisco.com Samer Salam CISCO Systems 595 Burrard St. Suite 2123 Vancouver, BC V7X 1J1 Canada Email: ssalam@cisco.com