Chapter 25

Call Routing in GSTN

Watson come here, I want you!

Alexander Graham Bell


In this chapter, we present how routing works in the global switched telephone newtork (GSTN). We disucss E.164 addressing for phone devices. We also discusses network and carrier addressing that are used for transfering a call between different providers. We also disuss SS7, the signalling network, and how this is used with circuits for the call network. Finally, we discuss local number portability and its impact on call routing.


call routing; PSTN; GSTN; E.164 addressing; SS7 signalling; local number portablity

Reading Guideline

The first part of this chapter can be read independently. Knowledge call routing (Chapter 19 ...

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