How to Cheat at VoIP Security
If VoIP engineering is not your specialty, this guide provides an introduction to VoIP security, and covers exploit tools and how they can be used against VoIP systems.
TABLE OF CONTENTS How to Cheat at VoIP Security
SIP Architecture
Though we ve discussed a number of the elements of SIP, there are still a number of essential components that make up SIP s architecture that we need to address. SIP would not be able to function on a network without the use of various devices and protocols. The essential devices are those that you and other participants would use in a conversation, allowing you to communicate with one another, and various servers may also be required to allow the participants to connect together. In addition to this, there are a number of protocols that carry your voice and other data between these computers and devices. Together, they make up the overall architecture of SIP.
SIP Components
Although SIP works in conjunction with other technologies and protocols, there are two fundamental components that are used by the Session Initiation Protocol:
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User agents, which are endpoints of a call (i.e., each of the participants in a call)
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SIP servers, which are computers on the network that service requests from clients, and send back responses
User Agents
User agents are both the computer that is being used to make a call, and the target computer that is being called. These make the two endpoints of the communication session. There are two components to a user agent: a client and a server. When a user agent makes a request (such as initiating a session), it is the User Agent Client (UAC), and the user agent responding to the request is the...
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