Hybrid Standalone DVR User Guide
3.4.11
Multicast Setup
Multicast is a transmission mode for data packets. Multicast sends IP datagrams to a group of receivers
in a single transmission. When there are multiple hosts to receive the same data packet, multicast is the
best option to reduce the bandwidth and the CPU load. The source host can send out just one data
packet. This function also depends on the relationship of the group member and the group.
Figure 3-36
Refer to the following list for detailed information.
•
IP multicast group address
o
224.0.0.0-239.255.255.255
o
“D” address space
-- The higher four-bit of the first byte=”1110”
•
Reserved local multicast group address
o
224.0.0.0-224.0.0.255
o
TTL=1 When sending out telegraph
o
For example:
-- 224.0.0.1 All systems in the sub-net
-- 224.0.0.2 All routers in the sub-net
-- 224.0.0.4 DVMRP router
-- 224.0.0.5 OSPF router
-- 224.0.0.13 PIMv2 router
DVR7800S-U Series Hybrid DVR User Guide
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