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Multicast Address Ranges

Link-Local

– 224.0.0.0/24 is the range used

– 224.0.0.1 – All Hosts

– 224.0.0.2 – All Routers

 

GLOP Addressing

– GLOP addressing is used to give anyone with their own registered public AS number their own globally unique multicast IP address range.

– 233.0.0.0/8 is the reserved GLOP range.

– 233.x.x.0/24 is the actual address you use, where x.x is the 2 bytes of your AS number.  If your AS was 54321, convert it to hex = D431.  Here D4 is the first byte, and 31 is the second byte.  D4 into Decimal is 212, and 31 into decimal is 49. So your range is 233.212.49.0/24

– The drawback is that it only works with 2 byte AS numbers

– GLOP doesn’t stand for anything, it’s just called GLOP

 

Administratively Scoped Addressess

– 239.0.0.0/8 is the reserved range

– IP addresses in this range should be filtered on the edge of the administrative boundary

– This range of IP’s are only guaranteed to be unique within the administrative boundary (eg, within the BGP AS)

 

Source Specific Multicast

–  232.0.0.0/8 is the reserved range for SSM

– Used to identify exactly what source & group a device wants to receive multicast traffic for

 

SDP/SAP

– 224.2.0.0/16 is the range used

 

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