Goal

This scenario is targeting the setting up of basic voice services for an institution. We are proposing a solution where the IP PBX is complementary to the PBX of the institution.
The features that we will be explored are:

• authenticated login
• user provisioning
• gateway to the PSTN
• gateway between SIP and ?.323
• local dial plan
• encryption (endpoint-to-endpoint)
• codec support
• handling of both numeric and alpha-numeric addresses
• accounting
• qos
• availability checks

Applicability

• SIP interface with SIP proxy (OpenSER)
• H.323 interface with H.323 gatekeeper (GnuGk)
• SIP to H.323 gateway (Asterisk)
• Radius authentication (FreeRadius, Radiator)
• LDAP identity management infrastructure (OpenLDAP)
• accounting (MySQL)

Discussion of the interconnection of the components

Prerequisites (OS, dependencies on other software)

• a PBX (to interface to local institution phones)
• a gateway (to connect from the IP world to the PBX)
• authentication infrastructure (Radius or LDAP)

Configuration (OS agnostic)

OpenSER - The SIP interface

Sample config for a typical OpenSER setup with:

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