CUBE

• Cisco unified border element
• session border controller, SIP trunk termination (≈ MPLS CE)
• SIP trunk: ≈ TDM circuit for PSTN, over IP
• translates between SIP and H.323
• transcoding
• codec filtering
• hides internal address ≈ proxy, back-to-back user agent (B2BUA)
• DTMF
• music on hold (MOH)