X25AM Programming Manual

Introduction

X25AM Programming Manual—527201-001

1-7

Call User Data (CUD) in Call Setup Packets

In the call clearing phase there are four types of Call Clearing packets:

•

Clear Indication

•

DTE Clear Confirmation

•

Clear Request

•

DCE Clear Confirmation

There are also various Restart, Clear, Reset Cause, and Diagnostic packet types. For

a list of the diagnostic codes used by X25AM, see Appendix A, Procedures Summary

for X25AM.

Call User Data (CUD) in Call Setup Packets

X25AM has been enhanced to enable specification of a call user data (CUD) field of up

to 16 bytes in a CALL REQUEST packet. The permitted length of the CUD field

depends on which protocol is configured for the particular subdevice. The CUD field

Figure 1-5. Call Setup Packet Format

0 DSN

0 0

VST0105.vsd

Bits

Facility Fields

Call User Data 1-16 Octets

Present in Call Request and Incoming

Call Packets Only

Facility Length

DTE Addresses

Calling DTE

Called DTE

Channel Identifier

Logical

Octet

8765

4321

PTI= CALL REQUEST/INCOMING CALLS or

CALL ACCEPTED/CALL CONNECTED

Address Lengths

Legend

Packet Type Identifier (PTI)