A new IRTF research group, Scalable Adaptive Multicast (SAM)
Research Group, has begun, with the appended charter.
Use sam-request at irtf.org to subscribe
to the mailing list. See http://www.samrg.org for
further information.
John Buford & Jeremy Mineweaser
========================================================================
The Scalable Adaptive Multicast (SAM) Research Group is chartered
to explore and research techniques which improve multicast
performance with respect to dimensions such as number of groups,
dynamics of group membership, dynamics of the network topology, and
network resource constraints. The RG will investigate approaches
based on application layer multicast (ALM), overlay multicast (OM),
and native IP multicast, as well as hybrid approaches. A key design
consideration is the placement of multicast state information along
the multicast path, including packet headers, end hosts, and network
nodes, where placement may be determined adaptively.
In SAM architectures, new protocols are expected to coexist and
integrate with native IP multicast protocols while offering more
flexible deployment options and scaling to support a greater number
of simultaneous multicast groups. Alternative technologies such as
end-system multicast and overlay multicast have been demonstrated,
but these mechanisms must be integrated into a unified architecture
and operational design.
Among the challenges to be addressed are: multicasting in topologies
with concatenated VPNs, such as the Global Information Grid (GIG);
ability to incorporate QoS mechanisms while retaining scalability;
integration with network- and application-layer security mechanisms;
and adaptation schemes which consider group-related factors, such as
group size, number of sources, membership dynamics, sensitivity
to delay, amount of state, state update rate, application data rate,
and other application-specific parameters, as well as network-related
factors, such as dynamics of topology, carrying capacity, and
connectivity.
Methods will be explored for group formation and discovery that
scale to large numbers of groups, accommodate highly dynamic group
membership, and support user-initiated small-group multicast in
which the group is defined as a set of explicitly addressed
endpoints. Further challenges include efficient multicast for
limited-resource nodes and access links, control mechanisms for
hybrid systems, approaches to optimization in the network, including
routing, and operation in mobile networks, including Mobile Ad-hoc
Networks (MANETs).
Deploying, diagnosing, debugging, and managing multicast services is
complex, particularly for services which span multiple administrative
domains. The RG will propose and evaluate tools and strategies for
deployment, operations, and management of SAM services.
The RG will select candidates for analysis and evaluation from
existing research results. Researchers are invited to submit new
approaches for further investigation. Through experimentation, the
RG seeks to deepen its understanding of the solution space and to
enable the identification of preferred solutions as a function of
dynamic network characteristics and the number of multicast sources,
receivers, and groups.
The expected findings of the RG include characterizing the problem
space, including driving scenarios, comparisons and analysis of
existing approaches, a SAM framework that supports multiple ALM/OM/
native/hybrid protocols, analysis of network infrastructure impact
when multicast traffic becomes a dominant flow in a network, and
deployment scenarios which are independent of but can support and
evolve with network infrastructure support for native multicast.
The findings are expected to be published in technical reports,
academic papers, and/or RFCs.
_______________________________________________
Ietf mailing list
Ietf(_at_)ietf(_dot_)org
https://www1.ietf.org/mailman/listinfo/ietf