Hi all,
Anyone can help with this SCTP multi-homing question? I've read the spec. (RFC 4960) and googled, but still it's quite hard to really understand the essentials of the multi-homing.
The question is based on the diagram as following, which is a SCTP association beteen End Point A and B, on each End Point has two IP addresses serving this SCTP association:
Node A Node B
IP A1 ------- IP B1
\ /
\ /
/\
/ \
IP A2 ------ IP B2
In this way, there are actually 4 physical links in this single association: A1 -> B1, A2 -> B2, A1 -> B2, and A2 -> B1.
The question is: among these 4 links, how many can be defined as Prime?
From the spec., it looks like only one pair of IP addresses (ig. A1->B1) can be defined as prime so all traffic actually just goes on this link only, however in this way it means that among the 4 available links, only one is bearing traffic in normal cases and all other 3 are standby in case of prime failure, it doesn't look like make sense if compare to the possibility of having 2 out of 4 as prime and other 2 as standby. Furthermore, in case of prime (say A1-> B1) failure, which of the other three will take over and how are they prioritized?
Thanks.
Kevin. Wong.
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