9
Cisco TelePresence System Codec C90 API Reference Guide
D14641.0 6 Codec C90 API Reference Guide TC5.0 November 2011.
© 2010-2011 Cisco Systems, Inc. All rights reserved. www.cisco.com
About the API
Basic Principles
The heart of the API is the API-Engine. This is
where all information is stored and processed.
The API-engine can be accessed by an easy-
to-use Command Line Interface called XACLI
using RS-232, Telnet or SSH, or by the XML
API Service (TXAS) over HTTP/HTTPS.
Working with the API-engine is very similar
to working with catalogues and les on
a computer. All information is stored in a
hierarchic tree structure which is accessible
from dierent interfaces.
• When accessing the API-engine using
XACLI (RS-232, Telnet or SSH), the
information is formatted in a proprietary
Command Line style or in XML formatting.
• When accessing the API-engine using
the TXAS interface (HTTP/HTTPS), XML
formatting is supported.
This is similar to viewing les on a computer.
Accessing catalogues on a Windows
computer using the Command Prompt gives
a dierent view than using Windows Explorer,
but the information is the same.
About Telnet
Telnet is disabled by default. Before
connecting to the codec using Telnet you will
need to enable the interface via either RS-232
or SSH.
The following command can be set from the
Administrator settings menu or from the API
command interface:
• xConguration NetworkServices
Telnet Mode: On
The API-Engine
The API-Engine is optimized for easy, yet
advanced, machine-machine interaction
between a Cisco system and an external
control application.
The main features can be summarized to:
1. Structuring of information
2. Addressing using XPath (XML Path
Language) or SimplePath
3. Feedback
API-Engine
RS-232
cable
Main types of information
• READ information (R)
• WRITE information (W)
• READ/WRITE information (RW)
(R) READ information. This is Status
Information about the system and system
processes, i.e. information generated by the
system.
Typical examples include: status about
ongoing calls, network status, conference
status etc. All status information is structured
in a hierarchy, making up a database
constantly being updated by the system to
reect process changes.
(W) WRITE information. This is Command
information the user/control application supply
to initiate an action.
Typical examples include: instructing the
system to place a call, adjust volume,
disconnect a call etc.
A command is usually followed by a set of
parameters to specify how the given action is
to be executed.
(RW) READ/WRITE information. This is
Conguration Information dening system
settings. This information can both be
supplied and read by the user/control
application. Typical examples include: default
call rate, baud rate of a serial port, enabling/
disabling of various features etc.
All conguration information is structured in
a hierarchy making up a database of system
settings. But for the Conguration information,
the data in the database can only be updated
by the user/control application.
XACLI
(XML)
TXAS
(XML)
HTTP/
HTTPS
Telnet/SSH
via LAN
Structuring of Information
An application programming interface (API)
can be seen as a gate where information is
exchanged between two systems – a control
application and a target system.
The control application transmits instructions
to the target system, while the target system
supplies information about how these
instructions are executed, in addition to other
system related information.
Consequently, the exchange of information
can be divided into:
1. Information owing from target. This
we call READ information (R). The (R)
should not be confused with the (r) used
to indicate required parameters in the
Commands tables.
2. Information owing to target. This we call
WRITE information (W).