IPO-WG http://www.ietf.org/internet-drafts/draft-poj-optical-multicast-00.txt

[Dimitri Papadimitriou <dimitri.papadimitriou@alcatel.be>]

- NAME OF I-D:

http://www.ietf.org/internet-drafts/draft-poj-optical-multicast-00.txt

- SUMMARY:

The concept of multicast has been widely discussed for packet-oriented 
networks. This proposal extends the multicast concept to optical
networks, by introducing the concept of light-tree which provide 
enhanced performance for networks services such as Video, Multimedia
and Broadband applications. 

This contribution reviews the architectural considerations of optical
multicast-capable networks and analyze the key tradeoffs when designing
these networks by taking into account potentially conflicting criteria. 
It also examines the issues in signalling protocol extensions for
optical multicast-capable networks. 

- RELATED DOCUMENTS

http://www.ietf.org/internet-drafts/draft-ietf-mpls-arch-07.txt
http://www.ietf.org/internet-drafts/draft-ietf-mpls-generalized-signaling-04.txt
http://www.ietf.org/interent-drafts/draft-ietf-mpls-generalized-cr-ldp-03.txt
http://www.ietf.org/interent-drafts/draft-ietf-mpls-generalized-rsvp-te-03.txt
http://www.ietf.org/internet-drafts/draft-ietf-mpls-cr-ldp-05.txt
http://www.ietf.org/internet-drafts/draft-ietf-mpls-multicast-05.txt
http://www.ietf.org/internet-drafts/draft-awduche-mpls-te-optical-03.txt
http://www.ietf.org/internet-drafts/draft-farinacci-mpls-multicast-03.txt
http://www.ietf.org/internet-drafts/draft-ghani-optical-rings-01.txt
http://www.ietf.org/internet-drafts/draft-kompella-mpls-bundle-05.txt
http://www.ietf.org/internet-drafts/draft-many-inference-srlg-00.txt
http://www.ietf.org/internet-drafts/draft-many-ip-optical-framework-03.txt
http://www.ietf.org/internet-drafts/draft-many-optical-restoration-00.txt
http://www.ietf.org/internet-drafts/draft-papadimitriou-optical-rings-00.txt
http://www.ietf.org/internet-drafts/draft-papadimitriou-enhanced-lsps-04.txt
http://www.ietf.org/internet-drafts/draft-rs-optical-bundling-01.txt

- WHERE DOES IT FIT IN THE PICTURE OF THE SUB-IP WORK

OPT (IP Over Optical)

Notice: this is the only document focused on optical multicast

- WHY IS IT TARGETED AT THIS WG.

Today, only point-to-point connection are targetted by the IPO WG
(i.e. lightpath), the concept of light-tree (i.e. point-to-multipoint
connection) is not addressed by the current framework document while
it appears (see below for justification) as an extension of the current
IPO WG developments. 

Ask the question of the future "impact" of optical multicast in
comparison with optical unicast deployment is more or less like today
try to find the utilization percentage of packet multicast protocols 
in IP networks deployment. Nevertheless, there is a clear relationship 
between packet and optical multicast developments, if the former 
succeeds the latter should follow "logically".

- JUSTIFICATION

Optical multicast or equivalently point-to-multipoint optical
connections (or light-trees) offers advantages in the following critical
aspects in comparison to optical unicast and the corresponding point-to
-point optical connections (or lightpath) use:
- Efficient 1+1 optical protection (which currently the most
  important usage of optical multicast since 1:2 optical splitters
  are the most common) that can be used as well into drop and continue 
  function for optical rings inter-connection  
- Improved performance (no store and forward) compared to packet-
  oriented multicast technology
- Reduction of the total number of transceivers in the optical
  network (when used in non-transparent optical networks).
- Overall network throughput improvement by reducing the number of
  wavelengths used per fiber link (i.e. minimizing the overall bandwidth
  usage per fiber link)