WG Action: Rechartered Interface to the Routing System (i2rs)

[The IESG <[e-mail]>]

The Interface to the Routing System (i2rs) working group in the Routing
Area of the IETF has been rechartered. For additional information please
contact the Area Directors or the WG Chairs.

Interface to the Routing System (i2rs)
------------------------------------------------
Current Status: Active WG

Chairs:
  Susan Hares <[e-mail]>
  Jeffrey Haas <[e-mail]>

Technical advisors:
  Jürgen Schönwälder <[e-mail]>

Assigned Area Director:
  Alia Atlas <[e-mail]>

Mailing list
  Address: [e-mail]
  To Subscribe: https://www.ietf.org/mailman/listinfo/i2rs
  Archive:
http://www.ietf.org/mail-archive/web/i2rs/current/maillist.html

Charter:

In an IP routed network, the routing system:

- Distributes topology and other state (network metadata)
- Uses this network metadata to determine the best paths to each given 
  reachable destination attached to the network
- Communicates these decisions to the forwarding plane of each 
  forwarding device in the network.

That is, the routing system is the collection of entities, protocols and 
processes that collectively build the forwarding tables that are 
exported into the entities that constitute the network's forwarding 
plane.

While processes participating in the routing system are often colocated 
with the local forwarding elements, this isn't a necessary condition. 
Thus, the routing system includes control plane protocols and processes 
that compute routes and paths for data packets, wherever the processes 
implementing those protocols and processes may be running.

I2RS facilitates real-time or event driven interaction with the routing 
system through a collection of protocol-based control or management 
interfaces. These allow information, policies, and operational 
parameters to be injected into and retrieved (as read or by 
notification) from the routing system while retaining data consistency 
and coherency across the routers and routing infrastructure, and among 
multiple interactions with the routing system. The I2RS interfaces will 
co-exist with existing configuration and  management systems and 
interfaces.

It is envisioned that users of the I2RS interfaces will be management 
applications,  network controllers, and user applications that make 
specific demands on the network.

The I2RS working group works to develop a high-level architecture that 
describes the basic building-blocks necessary to enable the specific use 
cases, and that will lead to an understanding of the abstract
informational models and requirements for encodings and protocols for the
I2RS interfaces. Small and well-scoped use cases are critical to  
constrain the scope of the work and achieve sufficient focus for the 
working group to deliver successful outcomes. Initial work within the 
working group will be limited to a single administrative domain.

The working group is chartered to work on the following items:

- High-level architecture for I2RS including considerations of policy 
  and security.

- Tightly scoped key use cases for operational use of I2RS as follows:
  o Interactions with the Routing Information Base (RIB). Allowing read 
    and write access to the RIB, but no direct access to the Forwarding 
    Information Base (FIB).
  o Filter-based RIBs include a match of fields in IP header plus other 
    IP packet format fields. The matches in the filter-based RIBs may be 
    ordered to allow appropriate sequencing of the filter.  Each match 
    contains an action which may be forwarding to a next hop address or 
    other actions.  I2RS will coordinate this work with appropriate 
    working groups in routing, security and  operations & management 
    areas.
  o Control and analysis of the operation of the Border Gateway Protocol 
    (BGP) including the setting and activation of policies related to 
    the protocol.
  o Control, optimization, and choice of traffic exit points from 
    networks based on more information than provided by the dynamic 
    control plane.
  o Distributed reaction to network-based attacks through rapid 
    modification of the control plane behavior to reroute traffic for 
    one destination while leaving standard mechanisms (filters, metrics, 
    and policy) in place for other routes.
  o Service layer routing to improve on existing hub-and-spoke traffic.
  o The ability to extract information about topology from the network.  
    Injection and creation of topology will not be considered as a work 
    item. Such topology-related models will be based on a generic 
    topology model to support multiple uses; the generic topology model 
    should support topology extension for non-I2RS uses.
  o Other use cases may be adopted by the working group only through 
    rechartering.

- Yang Data Models consistent with the use cases.  Such documents 
  should include an information overview.  The existing WG draft - 
  draft-ietf-i2rs-rib-info-model - that is just an informational model 
  can be completed or extended with the associated YANG data model.

- Requirements for I2RS protocols and encoding languages.

- An analysis of existing IETF and other protocols and encoding 
  languages against the requirements.


Milestones:
  Jul 2013 - Request publication of an Informational document defining
the problem statement
  Jul 2013 - Request publication of an Informational document defining
the high-level architecture
  Aug 2013 - Request publication of Informational documents describing
use cases
  Sep 2013 - Request publication of an Informational document defining
the protocol requirements
  Sep 2013 - Request publication of an Informational document defining
encoding language requirements
  Feb 2014 - Request publication of Standards Track documents specifying
information models
  Feb 2014 - Request publication of an Informational document providing
an analysis of existing IETF and other protocols and encoding languages
against the requirements
  Feb 2014 - Consider re-chartering