3.3.7

3.3.7 RELEASE

This message is sent by the user or the network to indicate that the equipment sending the message has disconnected the channel (if any), and intends to release the channel and the call reference, and that the receiving equipment should release the channel and prepare to release the call reference after sending RELEASE COMPLETE. See Table 3-41.

Table 3-41/Q.931

RELEASE message content

Message type: RELEASE Significance: local (Note 1) Direction: both
Information element	Reference (subclause)	Direction	Type	Length
Protocol discriminator	4.2	Both	M	1
Call reference	4.3	Both	M	2-*
Message type	4.4	Both	M	1
Cause	4.5	Both	O (Note 2)	2-32
Display	4.5	n ® u	O (Note 3)	(Note 4)
NOTES 1. This message has local significance; however, it may carry information of global significance when used as the first call clearing message. 2. Mandatory in the first call clearing message, including when the RELEASE message is sent as a result of an error handling condition. 3. Included if the network provides information that can be presented to the user. 4. The minimum length is 2 octets; the maximum length is network dependent and is either 34 or 82 octets.