SIP User Credentials in the ITSP environment – part 3

In this, the third part of the article, we will look at how the ITSP Proxy server handles outbound calls, paying particular attention to the authentication requirements and to the handling of Caller ID. You may also wish to refer back to part 1 where we reviewed the basic entities and concepts used to identify … Read more…

SIP User Credentials in the ITSP environment – part 2

In part 1 of this article we reviewed the basic entities and concepts used to identify a user, a handset or service. It discussed in detail how these entities are used to register devices, either simple single-line devices or SIP trunks. Now, in part 2, we will examine in more detail the handling of inbound … Read more…

SIP User Credentials in the ITSP environment – part 1

This three-part article reviews the SIP entities that identify a user, a handset or service and looks at how they are used to register devices, authenticate and identify users and route calls. The subtle differences in the use of these entities can be confusing, even to an experienced SIP technician. Handling of the entities in … Read more…

OpenSIPS vs Asterisk

OpenSIPS and Asterisk are both open source projects and both are used for Voice over IP. However, they perform quite different roles, have different capabilities and different strengths and weaknesses. This article reviews how they are so different and considers what role each product can play in the infrastructure of an Internet Telephony Service Provider … Read more…