SS7

AT&T’s Intelligent Call Processing (ICP) is a Signalling System 7 (SS7) based feature which works in conjunction with AT&T’s family of 800 Services. ICP provides an organization with a high degree of control over the routing of its incoming 800 calls. ICP supports this flexible call routing on a call-by-call basis.

The CRP is owned by the organization and is located on their premises. It is a computer or a group of networked computers that is interconnected to the AT&T SS7 network over dual 56 Kb/s A-links. ICP enables an organization to design the routing of their inbound 800 calls to best suit the needs of the business. The organization has complete control over the CRP and can readily modify the routing algorithms as their business needs change.

When a customer makes an 800 call to an organization that subscribes to ICP, a Network Control Point (NCP) in the AT&T Network queries the organization’s Customer Routing Point (CRP) for routing information on the call. The CRP sends its response to the NCP over SS7 A-links. In fact, both the query and response occur over the A-links.

Testing

CRPs are provided by a number of third party vendors. Network Services Interfaces perform testing on these CRPs to verify that they can correctly interconnect to the AT&T SS7 network. Testing is performed on the following SS7 layers: Message Transfer Part (MTP) layers 1-3, Signalling Connection Control Part (SCCP), Transaction Capabilities Applications Part (TCAP), and the Application Service Element (ASE), where the ASE is identified as the TCAP User in the figure below.