Welltech Dialogic SS7 Protocols ISUP - Manual (Page 26)

Section 6 Interface to Application
26
6.4 Parameter Extension Mechanism
The CCPN_parameter type value 128 (0x80) is used as an extension
parameter indicator. The parameter extension mechanism is used for all
parameter types whose decimal value is greater than 255 at the common
control interface. If a parameter value of 128 (0x80) is contained within a
message for sending to or received from the user, the actual parameter type
value (minus 256) is contained in the third byte which is subsequently
followed by the length of the parameter and its data as shown below:
Name Length Data
0x80 Parameter
Length + 2
Parameter
Name - 256
Parameter
Length
Parameter Data
1 byte 1 byte 1 byte 1 byte ‘Length’ bytes (1 to 253)
6.5 Application Messages to ISUP
The following table lists all application messages (message type
ISP_MSG_TX_REQ) sent to ISUP module by the user application:
Value Primitive Message
type
Dec Hex
Use
Alerting request ACM
CPG
6
44
0x06
0x2c
Indicates incoming called party being
alerted.
Application transport
request APM 65 0x41 To issue an application transport
message.
Charge request
(Generic) CRG 49 0x31 Carries charging information.
Circuit seized request SZE 199 0xc7 Used to initiate a continuity test call
and indicates that a circuit has been
seized for an outgoing call (but no
address information has yet been
sent).
Confusion request CFN 47 0x2f Requests that a confusion message is
sent.
Continuity request COT 5 0x05 Indicates whether the continuity test
succeeded.
Collection charging
request MPM 201 0xc9 Used to carry charging information.
End-to-end message
request PAM 40 0x28 Requests that an end-to-end message
is sent.
Facility request FAR
FAC
31
51
0x1f
0x33
Request activation of a particular
facility or action at another exchange.
FAA 32 0x20 Used to accept or reject a facility . Facility response
FRJ 33 0x21 Previously requested with a facility
request.
Forward transfer
request FOT 8 0x08 Send forward transfer to the network.
Information request SAM 2 0x02 Subsequent address digits for overlap
signaling.