Information element | Direction | Type | Length | Note |
---|---|---|---|---|
Protocol discriminator | Both | M | 1 | |
Call reference | Both | M | 2-* | |
Message type | Both | M | 1 |
3.1.5 DISCONNECT This message is sent by the user to request the network to clear an end-to-end connection or is sent by the network to indicate that the end-to-end connection is cleared. See Table 3-6. TABLE 3-6/Q.931 DISCONNECT message content Message type: DISCONNECT Significance: global 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 M 4-32 Progress indicator 4.5 (Note 1) O (Note 2) 2-4 Display 4.5 n ® u O (Note 3) (Note 4) Signal 4.5 n ® u O (Note 5) 2-3 NOTES 1 Included in the network-to-user direction if the network provides in-band tones. See Annex D for usage in the user-to-network direction. 2 Included by the network if in-band tones are provided. However, the user may include the progress indicator and provide in-band tones. See Annex D. In such cases the network will ignore this information element and will not convey the in-band tones. 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. 5 Included if the network optionally provides additional information describing tones.