Enterprises are moving beyond voice-centric nature of IP PBX to real-time IP communications such as presence, instant messaging, web/voice/video conferencing, voicemail and visual voicemail, real-time business applications and telepresence in an effort to maximize their IP network. Enterprises are also in the process of moving away from VoIP islands to peer-to-peer VoIP networks to facilitate business-to-business collaboration and/or federation.

As enterprises move away from TDM and deploy real-time IP communications services and interactive business applications such IP contact centers, referred to as Unified Communications (UC), they face significant challenges in security, interoperability, QoS and regulatory compliance. The SBC Core enables the delivery of secure, high-quality, real-time interactive communications by providing critical control functions needed for enterprises. 

Figure 1 shows how SBC platforms enable enterprises to control critical IP network borders to their centers that host VoIP/UC infrastructure.

Figure 1: SBC Controlling Enterprise Network Borders


Where the SBC control or functionality resides depends on how Sonus SBC is deployed in the enterprise network. In Enterprise scenario, the SBC controls the following:

  • SIP trunk connection between Service Provider and enterprise. This connection links the enterprise to the PSTN network.
  • Connections between the enterprise headquarter and remote branch offices via private WAN such as MPLS.
  • Connections between remote users and mobile employees.
  • Connection to service providers who offer hosted IP communication services or VoIP enabled business applications.

Enterprises will deploy SBC even if their service providers already have Session Border Controllers deployed on their network for some key reasons:

  • Security
  • Interworking
  • Demarcation
  • Session Management

Enterprises use the same SBC core requirements/features as service providers but with differences in the detailed functionality of these requirements.


To learn about Service Provider deployment scenarios, see Service Provider Deployment Scenarios.

To learn about H.323 deployment scenarios, see H.323 Deployment Scenarios