voip-info.org reports:

After several months of live testing VoIP operation in Europe and Asia, SS7 is now available for Asterisk. The LIBISUP solution is fully integrated with Asterisk and does not require any additional external equipment.

The SS7 LIBISUP library presents itself as a replacement of the LIBPRI library. This means that you can use the existing Asterisk zap features and applications. The configuration, dial plans, etc. work the same way as with PRI. Both the stable release and CVS Head are supported.

The product is immediately available under the Digium commercial licence.
For more information please write to
   
and describe your SS7 project.

Frequently asked questions on SS7 with Asterisk:

Q. We have some servers and digium card in our stock. What hardware
requirements (CPU/Memory) are needed to host TE410P cards?.

Any Zaptel compatible E1/T1/J1 card should be suitable for use with the LIBISUP. We have tested with Digium and Sangoma cards. The CPU and memory requirements are similar to PRI applications and depend how much traffic (i.e. transcoding, echo cancellation, etc.) the gateway is handling. Therefore the same platform requirements apply as in handling of PRIs. In the LIBPRI solution the SS7 protocol itself does not consume a great deal of CPU power or memory.

Q. How many signaling links can be established per server/card?

You could have a lot of SS7 signalling links in one system, but this is not how SS7 is normally used. Typically one link, and probably an extra on a different E1 for redundancy, is all you need. Each SS7 link can handle a lot of signalling traffic.

Q: Is the SS7 LIBISUP available as open source?

No, it is available only under Digium commercial license. One of the reasons is that the network operators will not allow open source SS7 solutions with their networks.