Cisco Unified Communications Manager (CallManager)

Call States Sent to SCCP Endpoints by Cisco CallManager

Document ID: 69267

Updated: Mar 07, 2006



This document describes defined call states that Cisco CallManager sends to Skinny Client Control Protocol (SCCP) endpoints such as Cisco 7960/7940 IP phones. However, these call states are not used by Cisco CallManager internally.



Cisco recommends that you have knowledge of Cisco CallManager.

Components Used

The information in this document is based on all versions of Cisco CallManager.

The information in this document was created from the devices in a specific lab environment. All of the devices used in this document started with a cleared (default) configuration. If your network is live, make sure that you understand the potential impact of any command.


Refer to Cisco Technical Tips Conventions for more information on document conventions.


The SCCP protocol is a Cisco protocol standard for real-time calls and conferencing over IP.

An H.323 proxy can be used to communicate with the Skinny client using the SCCP protocol. In such a case, the telephone is a Skinny client over IP, in the context of H.323. A proxy is used for the H.225 and H.245 signaling.

With the SCCP protocol architecture, the majority of the H.323 processing power resides in an H.323 proxy — the Cisco CallManager. The end stations (IP phones) run the Skinny client, which consumes less processing overhead. The client communicates with CallManager using connection-oriented (TCP/IP-based) communication to establish a call with another H.323-compliant end station. Once Cisco CallManager has established the call, the two H.323 end stations use connectionless (UDP/IP-based) communication for audio transmissions.

Call States

This list defines the call states that are sent to SCCP endpoints, such as Cisco IP phones by Cisco CallManager in SCCP protocol. Cisco CallManager functions as an H.323 proxy. These are not the call states used in Cisco CallManager internally. Instead, they are the call states sent from Cisco CallManager and understood by the SCCP endpoints:

  • 1—Off Hook

  • 2—On Hook

  • 3—Ring Out

  • 4—Ring In

  • 5—Connected

  • 6—Busy

  • 7—Line In Use

  • 8—Hold

  • 9—Call Waiting

  • 10—Call Transfer

  • 11—Call Park

  • 12—Call Proceed

  • 13—In Use Remotely

  • 14—Invalid Number

This Cisco CallManager trace shows that Cisco CallManager sent 2 (see boldface characters) to the SCCP endpoint. It represents the call state of On Hook.

03/01/2006 16:43:19.808 CCM|StationD:
    (0000044) CallState callState=2 lineInstance=1 

Related Information

Updated: Mar 07, 2006
Document ID: 69267