Normal outgoing call, TRACE CONTROL

The following example illustrates a normal outgoing call with TRACE CONTROL:

EZB2310I VC F810XU038    outgoing call to 00000039
EZB2311I VC F810XU038    call request packet sent (length=20)
EZB2000I 0000 ......h......... 0B081002 04008800 00003900 00003803
EZB2000I 0010 ....             420A0ACC
EZB2230I MCH XU038    packet received (length=5)
EZB2000I 0000 ...0.            0F0810F0 01
EZB2314I VC 0810XU038    call accepted by  user data
EZB2320I VC 0810XU038    NPSI logon LU VL038001
EZB2330I VC 0810XU038    call complete
 
EZB2336I VC 0810XU038    inactivity timer expired
EZB2353I VC 0810XU038    clear request packet sent (length=5)
EZB2000I 0000 .....            00011300 00
EZB2365I VC 0810XU038    clear sent
EZB2333I VC 0810XU038    packet received (length=1)
EZB2000I 0000 .                17
EZB2358I VC 0810XU038    clear confirmed
EZB2351I VC 0810XU038    connection terminated for 00000039: sent 5 
                         received 5 dropped 0
EZB2352I VC 010 closed

The steps involved in outgoing and incoming calls are similar. One important difference is that the virtual circuit identifier changes when the call is accepted (compare the EZB2311I and EZB2314I messages). This is related to the details of the NPSI programming interface.

X.25 experts should note that some X.25 packets do not appear in the trace because they are generated by NPSI without the direct involvement of the host application. Clear confirm is one example. Also, the sequence of events during closing can vary slightly in normal operation, and in some instances, benign VTAM® request failures can be reported with message EZB2411E.