T4
Expressway
The pair that lets a remote phone register
Sources and go deeper
Opened 2026-10. A row marked confirm has no link, because that page was not verified.
- Cisco. Cisco Expressway Series product support last checked 2026-10
- Cisco. Mobile and Remote Access through Cisco Expressway, X15.2 last checked 2026-10
- Protocol and ports. Cisco Expressway IP port usage (X14.3 and X15.0) last checked 2026-10
- Cisco. Cisco Unified Communications Manager product support last checked 2026-10
- Protocol and ports. CUCM 15 TCP and UDP port usage last checked 2026-10
- Cisco. Cisco Collaboration Preferred Architectures last checked 2026-10
- Community. Cisco Community, Collaboration knowledge base last checked 2026-10
- Wikipedia. Voice over IP (Wikipedia) last checked 2026-10
- Cisco. Collaboration 12 SRND book. confirm. The historical Collaboration 12 SRND path opened as a product listing, not the design book. Use the Preferred Architecture index, which was opened. last checked 2026-10
- Cisco. System Configuration Guide for CUCM, Release 15 last checked 2026-10
- Protocol and ports. IANA service names and port numbers last checked 2026-10
- RFC. RFC 3550, RTP last checked 2026-10
- RFC. RFC 8445, ICE last checked 2026-10
- Wikipedia. Real-time Transport Protocol (Wikipedia) last checked 2026-10
Expressway-C and Expressway-E
Expressway-C lives on the inside, next to CUCM.
Mobile and Remote Access
MRA lets a remote Cisco phone or Jabber register to CUCM through the Expressway pair.
Firewall and traversal
Open the ports your version's guide lists.
Sources and go deeper
Opened 2026-10. A row marked confirm has no link, because that page was not verified.
- Cisco. Cisco Expressway Series product support last checked 2026-10
- Cisco. Mobile and Remote Access through Cisco Expressway, X15.2 last checked 2026-10
- Protocol and ports. Cisco Expressway IP port usage (X14.3 and X15.0) last checked 2026-10
- Cisco. Cisco Unified Communications Manager product support last checked 2026-10
- Protocol and ports. CUCM 15 TCP and UDP port usage last checked 2026-10
- Cisco. Cisco Collaboration Preferred Architectures last checked 2026-10
- Community. Cisco Community, Collaboration knowledge base last checked 2026-10
- Wikipedia. Voice over IP (Wikipedia) last checked 2026-10
- Cisco. Collaboration 12 SRND book. confirm. The historical Collaboration 12 SRND path opened as a product listing, not the design book. Use the Preferred Architecture index, which was opened. last checked 2026-10
- Cisco. System Configuration Guide for CUCM, Release 15 last checked 2026-10
- Protocol and ports. IANA service names and port numbers last checked 2026-10
- RFC. RFC 3550, RTP last checked 2026-10
- RFC. RFC 8445, ICE last checked 2026-10
- Wikipedia. Real-time Transport Protocol (Wikipedia) last checked 2026-10