Cisco Unified Border Element: The Voice Gateway Of Voice Gateways

What is CUBE?

Creates a border to your voice network:

  • Protocol Interoperability
  • Address and Port Translations (ADDRESS HIDING)
  • Consolidated billing and CDR
  • Centralize Bandwidth Management

Can jump into codec negotiations or can go ‘transparent’

2 modes:

  • Media Flow Through
  • Media Flow Around

CUBE Configuration Example:

Signaling Protocols – What Works and What Doesn’t

All SIP to SIP signaling (Delayed/Early Offer)

All H.323 to H.323 signaling (Fast/Slow Start)

SIP to H.323:

  • Early Offer to Fast Start
  • Early Offer to Slow Start
  • Delayed Offer to Slow Start


  • Flow Through
  • Flow Around (codec transparent)

‘address-hiding’ – Voice NAT with SIP signaling