Hola! I've a doubt about how changeback should work, let's say we have a linkset with 4 links (1-0 to 1-3, SLS 0 to 3) and the following happens: 1. link 1-0 fails, changeover to 1-1 (COO on 1-1 with SLS=0) 2. link 1-2 fails, changeover to 1-1 (COO on 1-1 with SLS=2) 3. link 1-0 gets available, changeback from 1-2 (CBD on 1-1 with SLS=0) What happens with the traffic normally going thru 1-2 ? Q.704 reads: 4.4.1 When a previously unavailable signalling link becomes available again (see 3.2), signalling traffic may be transferred to the available signalling link by means of the changeback procedure. The traffic to be transferred is determined in accordance with the following criteria. 4.4.2 In the case when the link set, to which the available signalling link belongs, already carries signalling traffic on other signalling links in the link set, the traffic to be transferred includes the traffic for which the available signalling link is the normal one. Note that the assignment of the normal traffic to a signalling link may be changed during the changeback process taking into account, for example, system performance. The normal traffic is transferred from one or more signalling links, depending on the criteria applied when the signalling link became unavailable (see 4.3.2), and upon the criteria applied if any of the alternative signalling link(s) themselves became unavailable, or available, in the meantime. If signalling links in the linkset are still unavailable, and if it is required for load balancing purposes, signalling traffic extra to that normally carried by any link might also be identified for diversion to the signalling link made available, and to other available links in the linkset. This extra traffic is transferred from one or more signalling links. --------------- My understanding of it is that the traffic from 1-2 should continue going thru 1-1. libss7's interpretation differs and send that traffic thru 1-0. Is libss7 right? If so, where am I wrong? All the ss7 linksets I've access to are one-link, so cannot test what do other implementations do. Thanks, -- Horacio J. Pe?a horape at compendium.com.ar horape at uninet.edu
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