NCast PR-HD - Manual (Page 37)

NCast Presentation Recorder Reference Manual
5.7. E DIT C HANNEL – N ETWORK
5.7.1. Set Video Stream Destination - Address
An address entered for Video (the Video or Graphics media stream) will be either a valid multicast address,
or the numeric host IP address of the remote unit if a point-to-point connection is being established.
A full discussion of multicast addressing is beyond the scope of this document, but briefly summarized, there
are three classes of multicast addresses typically used by multicast applications:
Global Addresses – The range of multicast addresses 224.0.1.0-238.255.255.255 are used for global
communications. These addresses are dynamically allocated and not statically reserved. These addresses
are unsuited for static assignment in the Channel Table.
GLOP Addresses – A document, IETF RFC 3180, describes a mechanism for statically assigned multicast
addresses in the address space 233/8 based on a formula that incorporates the Autonomous System (AS)
number in the middle two octets. The AS number is owned by the ISP providing service to the account and
use of a GLOP address must be coordinated with that ISP.
Administratively Scoped Addresses – The multicast address range of 239.0.0.0 to 239.255.255.255 has
been defined to be a range of administratively scoped multicast addresses in IETF RFC 2365. These
addresses may be statically assigned by the administrator of an organization’s network, and there will be no
conflict with other organization’s use of these addresses because border routers on the edge of an
organization’s network enforce policies to stop multicast traffic flow for addresses within this range. Further,
these same border routers can enforce policies so that subsets of these addresses are contained within
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