org.mjsip.server.sbc

Class SessionBorderController

java.lang.Object

org.mjsip.server.ServerEngine

org.mjsip.server.Registrar

org.mjsip.server.Proxy

org.mjsip.server.sbc.SessionBorderController

All Implemented Interfaces:

SipProviderListener

public class SessionBorderController
extends Proxy

Class SessionBorderController implements a SIP proxy acting as simple Session Border Control (SBC).

The SBC forces both signaling and media flows to transit through it. It do this by using Record-Route header field, by mangling contact and request-URI addresses, and by mangling SDP content (actually the 'c' and 'm' fields).
If the same message has spiralelly passed to the SBC more times, the contact address is mangled recursively each time.

For media flows the SBC operates as media relay.
Currenly no RTP transcoding is implemented, and just rough UDP relay is performed.

A SBC can be used for example to assist an UA (e.g. a softphone) to communicate through NAT middle-boxes (using symmetric RTP).

It works dinamically and allows an UA to change its point of attachment without loose the SBC connectivity and relay functinality.

A SBC is created by the SessionBorderController() costructor based on:
- a ServerProfile containg general proxy configuration,
- a SessionBorderControllerProfile containg the specific SBC configuration.

SBC uses a set of media ports assigned cyclically to new media relays (when the last port is in-use, the first port is re-used). The set of available media ports is also taken by the SessionBorderControllerProfile.

Field Summary

Fields

Modifier and Type	Field and Description
protected SessionBorderControllerProfile	sbc_profile The SBC configuration
protected ExtendedSipProvider	sip_provider The ExtendedSipProvider.

Fields inherited from class org.mjsip.server.ServerEngine

as, AUTHENTICATION_SCHEMES, AUTHENTICATION_SERVER_CLASSES, authentication_service, AUTHENTICATION_SERVICE_CLASSES, AUTHENTICATION_SERVICES, location_service, LOCATION_SERVICE_CLASSES, LOCATION_SERVICES, logger, Loop_Tag, server_profile

Constructor Summary

Constructors

Constructor and Description
SessionBorderController(ExtendedSipProvider sip_provider, ServerProfile server_profile, SessionBorderControllerProfile sbc_profile) Costructs a new SessionBorderController.

Method Summary

Modifier and Type	Method and Description
protected boolean	doRelay(java.lang.String remote_addr) Whether acts as relay system for that remote host.
static void	main(java.lang.String[] args) The main method.
void	processRequestToLocalUser(SipMessage msg) When a new request message is received for a local user.
protected SipMessage	updateProxyingRequest(SipMessage req) Processes the Proxy headers of the request.
protected SipMessage	updateProxyingResponse(SipMessage resp) Processes the Proxy headers of the response.
protected SipMessage	updateRegistration(SipMessage msg) Updates the registration of a local user.

Methods inherited from class org.mjsip.server.Proxy

getAuthDomainBasedProxyingTarget, getAuthPrefixBasedProxyingTarget, getDomainBasedProxyingTarget, getPrefixBasedProxyingTarget, isPhoneNumber, processRequestToLocalServer, processRequestToRemoteUA, processResponse

Methods inherited from class org.mjsip.server.Registrar

getTargets

Methods inherited from class org.mjsip.server.ServerEngine

getLocalDomains, isResponsibleFor, isResponsibleFor, isResponsibleFor, onReceivedMessage, validateRequest

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

sip_provider

protected ExtendedSipProvider sip_provider

The ExtendedSipProvider. It overrides org.mjsip.sip.provier.SipProvider

sbc_profile

protected SessionBorderControllerProfile sbc_profile

The SBC configuration

Constructor Detail

SessionBorderController

public SessionBorderController(ExtendedSipProvider sip_provider,
                               ServerProfile server_profile,
                               SessionBorderControllerProfile sbc_profile)

Costructs a new SessionBorderController.

Parameters:

sip_provider - is the SIP transport provider

server_profile - the ServerProfile cointaining basic server confiuguration

sbc_profile - the SessionBorderControllerProfile cointaining specific SBC network configuration.

Method Detail

processRequestToLocalUser

public void processRequestToLocalUser(SipMessage msg)

When a new request message is received for a local user.

Overrides:

processRequestToLocalUser in class Proxy

updateProxyingRequest

protected SipMessage updateProxyingRequest(SipMessage req)

Processes the Proxy headers of the request. Such headers are: Via, Record-Route, Route, Max-Forwards, etc.

Overrides:

updateProxyingRequest in class Proxy

updateProxyingResponse

protected SipMessage updateProxyingResponse(SipMessage resp)

Processes the Proxy headers of the response. Such headers are: Via, ..

Overrides:

updateProxyingResponse in class Proxy

updateRegistration

protected SipMessage updateRegistration(SipMessage msg)

Updates the registration of a local user. This method is called only if the SBC works also as Registrar.

Overrides:

updateRegistration in class Registrar

Returns:

it returns the response message for the registration.

doRelay

protected boolean doRelay(java.lang.String remote_addr)

Whether acts as relay system for that remote host.

main

public static void main(java.lang.String[] args)

The main method.