Expressway-C can now be used as a SIP registrar for telepresence room and desktop systems. We have also
introduced a new licensing model for calls that go through the Expressway, to align more closely with the Unified CM
licensing model.

When you configure the Expressway as a registrar, you must license it for concurrent systems (CUCM model), rather
than for concurrent calls (VCS model). You can do that by adding either or both of the following license types to the
Expressway-C:

■

TelePresence Room System License

■

Desktop System License

The following devices register as desktop systems with all other devices considered room systems:

■

Cisco TelePresence EX60

■

Cisco TelePresence EX90

■

Cisco DX70

■

Cisco DX80

Scope of the registrar feature:

■

Option keys containing licenses for local registrations are installed on the Expressway-C.

These licenses are pooled in a cluster, that is, Expressway-C peers can use each others' licenses. However,
rooms cannot use desktop licenses, nor can desktop systems use room licenses.

■

Registrations from outside the network are proxied to the Expressway-C by the Expressway-E. The
Expressway-E cannot accept direct registrations.

Cisco Expressway Administrator Guide

Introduction