Path/association retransmit in "show cs7 asp detail"

Question

Hi, all
I wonder exact meaning of the path retransmit and assoc retransmit in "show cs7 asp detail"
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SG1#sh cs asp detail
ASP name: MTS_A Type: SUA
Availability: enabled ASP id: n/a
SCTP association state: established Association id: 0xA1010009
AS name: MTS ASP state: active Mate state: active
Traffic mode: ldshr bnd, wt: 1 , dist: no
Active Time: 1w5d
Configured remote port: 17003 Actual remote port: 17003
Configured remote ip addresses: 10.7.53.11
10.7.54.11
Actual remote ip addresses: 10.7.53.11 State: active (effective prim)
Local port: 17003
Offload to linecard: Yes Slot: 10 1 AspVipId: 101
ASP protocol class capability: class 0, class 1
ASP interworking with SS7 networks capability: ASP
Local receive window: 64000 Cumulative sack timeout: 200 ms
Assoc retrans: 10 Path retrans: 4
Max init retrans: 8 Max init RTO: 1000 ms
Minimum RTO: 1000 ms Maximum RTO: 1000 ms
Bundle status: on Bundle timeout: 5 ms
Keep alive status: true Keep alive timeout: 30000 ms
SCTP congestion level: 0 SCON congestion level: 0
Unordered priority: equal Transmit queue depth: 1000
Initial cwnd: 3000 Idle cwnd rate: 50
Retrans cwnd rate: 50 Retrans cwnd mode: RFC
FastRetrans cwnd rate: 50
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I think "Path retrans = 4" means time of re-try for each path(primary path, secondary path)
and "Assoc retrans = 10" means time of re-try for association.
if assocation has primary and secondary path(it has two paths)and both path is not available in the far-end.
ITP will try to transmit the chunk(packet) to SEP(Signaling End Point)
first it try into the primary path => would be fail because the far-end down.
second it try into the secondary path => would be fail because the far-end down.
above operation will repeat 4 times.
then itp(SG:signaling gateway) will knows every path is not available.
then what is the "Assoc retrans = 10", is it the sum of the fail(primary path fail + secondary path fail)
primary path fail = 4
secondary path fail = 4
association fail = 8 (as I think!!)
what is the exact meaning of "the Assoc retrans = 10"??
who knows about this?

Answer 1

Your assumption is bascially correct.
Pathretrans is per destination address.
Association retrans is when the ASP is declared inactive.
Sections 8.1 and 8.2 do a great job of explaining these retransmission counters...
Section 15 lists recommended settings for these values...
http://www.rfc-editor.org/rfc/rfc4960.txt
Now, ITP defaults to 4 per dest and 10 for the association...which is ok as well because ITP declares ASP inactive either when there is no active addresses or when assoc retransmit value is reached.
They left these values as the default because before initial config, the ITP is not aware of how many peers will be in the multihome config and these defaults will be ok in most cases.