Feature history for Cisco unified border element

Updated: April 24, 2026

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Provides the feature history and release information for Cisco Unified Border Element functionality.

This reference lists the feature history for Cisco Unified Border Element (CUBE) and related voice functionality, including release information and descriptions of each feature enhancement.

Table 1. Feature history
Feature Name	Release Information	Description
Cisco Unified Border Element (CUBE)	Cisco IOS XE Catalyst SD-WAN Release 17.7.1a Cisco vManage Release 20.7.1	Cisco Unified Border Element (CUBE) interconnects voice and video connectivity between VoIP networks. It enables enterprise voice networks to communicate with Internet telephony service providers (ITSPs) and provides Session Border Controller (SBC) functionalities.
Secure SRST Support on Cisco Catalyst SD-WAN	Cisco IOS XE Catalyst SD-WAN Release 17.10.1a Cisco vManage Release 20.10.1	Secure SRST Support on Cisco Catalyst SD-WAN allows you to configure Cisco Survivable Remote Site Telephony (SRST) commands and additional Cisco Unified Border Element (CUBE) commands. Using these commands within Cisco IOS XE Catalyst SD-WAN devices, you can: Maintain voice services at remote sites during network outages. Extend advanced voice and video connectivity within Cisco Catalyst SD-WAN You can configure these commands onCisco IOS XE Catalyst SD-WAN devices using Cisco SD-WAN Manager device CLI templates or CLI add-on feature templates.
Supported Voice and SIP-UA Commands	Cisco IOS XE Catalyst SD-WAN Release 17.14.1a Cisco Catalyst SD-WAN Manager Release 20.14.1	This feature provides support for specific commands that enhance voice and SIP-UA functionalities on Cisco IOS XE Catalyst SD-WAN devices. These commands include: cipher (voice class) nat media-keepalive secure-ciphersuite transport tcp tls (SIP-ua) voice-class SIP nat media-keepalive
Survivable Remote Site Telephony (SRST) commands	Cisco IOS XE Catalyst SD-WAN Release 17.14.1a Cisco Catalyst SD-WAN Manager Release 20.14.1	This feature provides support for specific commands related to secure HTTP client communication and `call-manager-fallback` transport. These commands include: HTTP client secure-ciphersuite transport-tcp-tls (call-manager-fallback)

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