ETSI - TS 102 461
Satellite Earth Stations and Systems (SES); Broadband Satellite Multimedia (BSM); Multicast Source Management
|Publication Date:||1 July 2015|
The present document defines the architectures and functions required for the interworking of IPv4 multicast protocols, including multicast sources, with the BSM.
The present document builds upon previous BSM documents referenced in clause 2, and notably ETSI TS 102 294  on BSM Multicast Functional Architecture.
The present document firstly considers the BSM network scenarios for IP multicast interworking, with two main aspects:
1) the satellite network architecture;
2) the management of multicast sources and data forwarding, either statically or dynamically.
The BSM functional and protocol architectures are then derived for management of:
• IP multicast control messages (group management and routing protocols);
• Multicast access control (including resource management); and
• Multicast address resolution.
The present document then defines the detailed functional requirements and interactions of the above three functions with respect to the BSM lower layer interface, the SI-SAP. The Satellite-Dependent (SD) functions below this interface are system specific and are not treated here.
In the case of multicast routing protocols, the PIM-SM protocol IETF RFC 4601  (including the PIM-SSM IETF RFC 3569 [i.5], IETF RFC 4607 [i.9], IETF RFC 4608 [i.10] variant) is taken as the basis for the present document since it is almost exclusively used in existing and proposed multicast routing applications today.
IPv6 protocols are not explicitly covered in the present document.
To make multicast an effective service over the BSM, multicast should take advantage of satellite's native multicast capabilities. Unlike Unicast, where destination IP and link layer addresses are specific to an end host, multicast employs a common IP "group" address for a given flow to all receivers, and therefore the BSM SI-SAP should also employ a corresponding common address, or GID (Group ID), for each multicast flow. The way in which these GIDs are controlled and employed is also defined in the present document.