Developer's Guide

CHAPTER
3-1
CTI Server Message Reference Guide (Protocol Version 15) for Cisco Unified Contact Center Enterprise
Release 8.5(1)
3
Messaging Conventions
Communication between the CTI client and the CTI Server is accomplished by the exchange of
messages. Cisco’s CTI Server message set is modeled after the Computer-Supported
Telecommunications Applications (CSTA) messaging conventions defined by the European Computer
Manufacturers Association. CTI Server messages, in general, follow CSTA naming conventions and the
request/confirmation and unsolicited event paradigms. However, CTI Server messages use a simpler set
of data types than those defined by CSTA.
In the CSTA model, one party acts as a server and the other as a client. In the Cisco interface, as the
names suggest, the CTI client takes the client role and issues requests to the Unified CCE. The Unified
CCE CTI Server takes the server role, responding to requests from the CTI clients and originating
unsolicited events.
This chapter provides the following information about CTI Server messages:
• A list of the complete CTI Server message set
• A description of the following CTI Server message components:
• Data Types
• Floating Fields
• Invoke IDs
• Call Event Data
• The format for CTI Server failure indication messages
Message Types
Table 3-1 defines the complete CTI server message set. The messages are described in greater detail in
the remainder of this document. The length of the largest possible message (including the message
header) defined by this protocol is 4329 bytes.
Ta b l e 3 - 1 M e s s a g e S e t
Number Message Type Purpose
1 FAILURE_CONF Negative confirmation; may be sent in
response to any request.
2 FAILURE_EVENT Unsolicited notification of a failure or error.
3 OPEN_REQ Communication session establishment
request.