L2VPN Service Model
charter-ietf-l2sm-01

Document Charter L2VPN Service Model WG (l2sm)
Title L2VPN Service Model
Last updated 2016-11-04
State Approved
WG State Active
IESG Responsible AD Benoit Claise
Charter Edit AD Benoit Claise
Send notices to (None)

Charter
charter-ietf-l2sm-01

The IETF and the industry in general is currently specifying a set of YANG
models for network element and protocol configuration. This is an essential
first step, but the end goal is a full system configuration that enables service
agility to speed service creation and delivery and allows the deployment of
innovative new services across networks. Services are built from a combination
of network element and protocol configuration, but are specified to service
users in more abstract terms.

The Layer Two Virtual Private Network Service Model (L2SM) working group is a
short-lived WG. It is tasked to create a YANG data model that describes a L2VPN
service (a L2VPN customer service model). The model can be used for
communication between customers and network operators, and to provide input to
automated control and configuration applications.

It is recognized that it would be beneficial to have a common base model that
addresses multiple popular L2VPN service types. The working group will derive a
single data model that includes support for the following:
- point-to-point Virtual Private Wire Services (VPWS),
- multipoint Virtual Private LAN services (VPLS) that use LDP-signaled
Pseudowires
- multipoint Virtual Private LAN services (VPLS) that use a Border Gateway
Protocol (BGP) control plane as described in RFC4761 and RFC6624
- Ethernet VPNs specified in RFC 7432.
Other L2VPN service types may be included if there is consensus in the working
group.

It needs to be clearly understood that this L2VPN customer service model is not
an L2VPN configuration model. That is, it does not provide details for
configuring network elements or protocols: that work is expected to be carried
out in other protocol-specific working groups. Instead, the L2VPN customer
service model contains the characteristics of the service as discussed between
the operators and their customers. A separate process is responsible for mapping
this customer service model onto the protocols and network elements depending on
how the network operator chooses to realise the service.

The deliverable from this working group will provide information that other
working groups can use to evaluate the set of YANG models that they have already
developed or that are under development. This will help them to identify any
missing models or details. Thus, the deliverable can be viewed as driving
requirements for service delivery models so that the customer service parameters
can be mapped into inputs used by the protocol configuration models.

The working group will learn from the experience of the L3SM working group and
it is expected that the L2SM data model will have similar structure to the L3SM
data model to enable benefits of common code, provide shared user experience,
and leverage discussions that took place during the L3SM development.

The working group should consider draft-wen-l2sm-l2vpn-service-model as a
starting point.

The working group will coordinate with other working groups responsible for
L2VPN protocol work (most notably with BESS and PALS). It will also coordinate
with other organizations working on related L2VPN data models (such as the
MEF).