Polycom VSX Series manual Cause Codes, Code Cause Definition

Appendix

Q.850 Cause Codes

The following table describes codes that the ISDN switch sends to the VSX system to indicate call status. Although the codes are standardized, each ISDN service provider defines them differently. Because of this, the definitions in the table may not exactly match the messages that you see.

Code	Cause	Definition
1	Unassigned number	The switch received the sent ISDN number in the
		correct format, but no destination equipment uses
		the number.
2	No route to specified	The ISDN exchange does not recognize the
	transit network	intermediate network through which to route the
		call.
3	No route to	The intermediate network through which the call is
	destination	routed does not serve the destination address.
6	Channel	The specified channel does not provide adequate
	unacceptable	service quality to accept the requested
		connection.
7	Call awarded and	The user is assigned an incoming call that is being
	delivered	connected to a call channel that has already been
		established for this user and this type of call.
16	Normal call clearing	The originator or receiver of the call has requested
		that it be cleared.
17	User busy	All B channels are in use; the called system
		acknowledges the connection request, but is
		unable to accept the call.
18	No user responding	The destination equipment does not respond to
		the call, so the connection cannot be completed.
19	No answer from	The destination equipment did not complete the
	user (user alerted)	connection within the prescribed time after
		responding to the connection request. The
		problem is at the remote end of the connection.
21	Call rejected	The destination equipment is capable of accepting
		the call, but has rejected it for an unknown reason.
22	Number changed	The ISDN number used to set up the call is no
		longer valid. (The diagnostic field of the message
		may return an alternate address assigned to the
		called equipment.)
26	Non-selected user	The destination is capable of accepting the call,
	clearing	but did not assign it to the user.

Appendix - 11