Session Border Controller - Theory of Operation

What is an SBC

SBC stands for Session Border Controller

• Simplified Explanation

  • SIP Firewall

  • SIP Security Device

Session

• Real time interactive communications

• Voice, Video, multimedia

• SIP or H323 Signaling

Border

• IP to IP network border

• SIP trunks to service providers

• Remote worker access

• Internal Enterprise / External Enteprise

Control

• Security & SLA assurance

• Revenue & cost optimization

• Compliance

Why use an SBC

SBC are installed at the edge of VoIP Networks to facilitate end to end VoIP transmission without compromising network security

Essential for Several reasons:

• New security issues introduced with SIP protocol

• Fix Interoperability issues

• Implementation of UC/Collaboration features

SBC are typically implemented as Back to Back User Agents (B2BUA)

• All SIP and Media (voice) traffic transit through SBCs

B2BUA Explained

• A back to back user agent (B2BUA) is a logical network element in the Session Initiation Protocol (SIP) applications

• It operates between two endpoints in a communication session and divides the communication channel into two different call legs

• It mediates SIP signalling between both ends of the call

• B2BUAs are often implemented within media gateways

Open

What are User Agents?

Open