We know that SIP is in the p2p session layer of the OSI mode and used to setup voip sessions and that a SIP Servlets must be executed within a SIP Servlets Container, which implements the SIP Servlet specification. Mobicents sip servlets have been extensively used to create , deploy and manage VOIP services. Also it has a converged application server where a web application is composed of one or more HTTP Servlets and one or more SIP Servlets.
Mobicents runs atop Jboss Application server and integrates sip protocol stack. Its roles
- Handle the communication with the client.
- Persist the data and handle communication with the database.
- Execute the Beans which is a server-side component that encapsulates the business logic of an application
- Provide clustering, fail-over and load-balancing.
- Local memory access / caching.
- Manage transactions
The Mobicent server bears 50% resemblance to Rhino TAS .
Mobicents application routers
Mobicents Sip Servlets ships with a default application router (DAR) which selects which application to execute in a container for a request.
So far , I have successfully done the following
1. installed the Mobicent platform on Linux machine
2.set up the environment to build and deploy the applications
sip server types
1.Mobicents as registrar
registrar is aware of the IP address of the client so when UA wants to opena dialog it contacts registrar for the address of the callee
2. Back to back user agent on mobicents sip server
B2BUA acts as an endpoint for two other agents and forwards requests and responses between those two agents. Unlike proxy servers , B2nua server maintain state for dialogs and transactions.
3. proxy application using Mobicents sip servlets
A SIP proxy is an agent which stands in the path of two UA. The proxy is used only for the INVITE request and answer. The following ACK is then sent directly from one UA to another. The main purpose of the SIP proxy is to route the INVITE request between the UA’s.
4. Mobicents as sip load balancer
The Mobicents SIP load balancer acts as an entry-point for the cluster. Can handle both SIP and HTTP traffic. Distributes the SIP messages among the alive nodes ( use a attributable algorithm) after checking their heartbeat.
The load balancer appends itself to the Via header of each request. Thus, responses are sent to the SIP load balancer before they are sent to the originating SIP application
tbd : Attached are the screen shots of the same .
1. User agent client (UAC) Dialog
2. User agent server (UAS) Dialog
3. Mobicent slee management console
4. Joboss status console
5. Admin console depicting applications installed .
Telecom R & D 