Source Packet Routing in Networking
charter-ietf-spring-00-02

The SPRING working group will define procedures that will allow
a node to steer a packet along an explicit route through
the SPRING region without requiring path state to be
maintained by transited nodes. A SPRING region is a network
comprised of nodes (which may be of any type, including
routers and appliances) that share the following
trust model: any node in the SPRING region is trusted to steer
a packet along any path within the region. The SPRING region may comprise one
or more ASes, or even less than a single AS. Although a
region may comprise more than one AS, initial work will
focus on the intra-domain, that is, single AS, scenario.

The procedures should support both centralised and distributed path
computation. The procedures should also cover support for OAM
functions.

Where use cases are documented, care should be taken to define the
data plane requirements for the environment within which they are
to be implemented. The procedures should avoid modifications to
the MPLS data plane, in order to remain compatible with existing
extensive deployments of MPLS. It is anticipated that the procedures
may require modifications to the IPv6 data plane. While the initial
focus of the SPRING WG is on the intra-domain deployment scenarios
(see below), the modifications to the IPv6 data plane must support
both intra and inter-domain deployment scenarios.

Where possible, existing protocols must be used to implement the
SPRING function. Any modification or extension of existing architectures
or protocols must be carried out in the working groups responsible for
the architectures or protocols being modified in co-ordination with
this working group, but may be done in this working group after
agreement with all the relevant WG chairs and responsible ADs
The SPRING working group is chartered for the following list of
items:

o Identification and evaluation of use cases for which there
is consensus within the WG.
o Definition of new procedures, driven by the use cases and underlying
technology. The new procedures must cover security considerations
(including the relationship between networks forming the SPRING
region) and allow for solutions which substantially improve upon
current technologies by defining requirements, extensions, or new
functionality in existing routing, management or other protocols.
o Determine whether the above mentioned procedures require
modification/changes to the existing MPLS architecture, and
if so, then document requirements for such modifications/changes.
o Determine whether the above mentioned procedures require
modification/changes to the existing IPv6 architecture, and
if so, then document requirements for such modifications/changes.
o The SPRING working group will then develop solutions, focusing
initially on intra-domain deployment scenarios. Where such
solutions utilize existing protocols (IS-IS, OSPF, BGP, PCE) this will
be done in conjunction with the responsible IETF working group. Work
on new protocols may be carried out by the SPRING working group.

The working group will develop the following documents:

o One or more documents describing SPRING use cases,
o Specification of new procedures to support SPRING use cases,
o Requirements for changes to MPLS architecture, if needed,
o Requirements for changes to IPv6 architecture, if needed,
o Document interworking and co-existence between the new procedures
and the existing MPLS signaling protocols (LDP, RSVP-TE, BGP),
o Document impact (if any) of any proposed IPv6 data plane modifications
on existing deployment of IPv6,
o A set of one or more protocol extensions requirements documents,
o Inter-operability reports pertaining to the implementation of extensions
supporting SPRING.