FEC Onlineservices
 
X.25 over ISDN
Preliminary notes
X.25 packets were transmitted usually over a public X.25 network (Datex P). The ISDN network offers a cost-efficient alternative. The X.25 packets can be transmitted either over an ISDN D channel (X.31) or an ISDN B channel. The following scenario shows an example of incoming X.25 calls using an ISDN B channel.

Scenario

Requirements
The bintec router X8500 needs a X.25 license. The running system software is 7.4.1p13.
 

Configuration
This example shows the configuration of the bintec X8500 using the "Setup Tool".

ISDN configuration
If you want to use the PRI interface for incoming X.25 calls, you have to configure the service "X25 over ISDN" with an unique MSN number.

X8500 Setup Tool                                     BinTec Communications AG
[SLOT 5 UNIT 0 ISDN S2M][INCOMING][ADD]                              x8500
_______________________________________________________________________________

          Item                X.25 over ISDN
          Number              85555
          Mode                left to right (DDI)

          Bearer                 any

                    SAVE                               CANCEL
X.25 configuration
Please add an entry to allow incoming ISDN calls in the menu "X25 over ISDN".

X8500 Setup Tool                                     BinTec Communications AG
[X.25][X25 OVER ISDN][EDIT]                                          x8500
_______________________________________________________________________________

   Interface: 27001 Name: Filiale               Type:   one to one

   ISDN Numbers >
   Signalling:

   Dial Parameters:

   Layer 1 Parameters:
     Protocol: auto                          Modem Profile: 1

   Layer 2 Parameters:
     Protocol: auto           Mode: auto  PAD Profile: 0

 
                    SAVE                               CANCEL
Please add 2 following entries in the menu "Link Configuration". The first entry is for the ISDN interface:

X8500 Setup Tool                                     BinTec Communications AG
[X.25][LINK][EDIT]                                                   x8500
______________________________________________________________________________

          Link                            Filiale
          L3 Mode                         dte
          L3 Packet Size                  default: 256        max: 256
          L3 Window Size                  default: 4          max: 4
          Windowsize/Packetsize Neg.      when necessary (default)
          Logical Channel Number 0        disable
          Lowest Two-Way-Channel (LTC)    1
          Highest Two-Way-Channel (HTC)   15


          L2 Window Size                  2
          Layer 2 Behaviour               disconnect when idle

                    SAVE                               CANCEL
The second entry is for the Ethernet interface (connection to the X.25 server):

X8500 Setup Tool                                     BinTec Communications AG
[X.25][LINK][ADD]                                                    x8500
_______________________________________________________________________________

          Link                            en0-1-llc
          L3 Mode                         dce
          L3 Packet Size                  default: 4096       max: 4096
          L3 Window Size                  default: 7          max: 7
          Windowsize/Packetsize Neg.      when necessary (default)
          Logical Channel Number 0        disable
          Lowest Two-Way-Channel (LTC)    1
          Highest Two-Way-Channel (HTC)   1024
          Partner MAC Address (LLC)       0060b007fab07c

          L2 Window Size                  7
          Layer 2 Behaviour               always active

                    SAVE                               CANCEL
Please add an entry in the menu "Routing" to route incoming X.25 calls from the ISDN interface to the Ethernet interface.

X8500 Setup Tool                                     BinTec Communications AG
[X.25][ROUTING][ADD]                                                 x8500
_______________________________________________________________________________

          Source Link                     Filiale
          Destination Link                en0-1-llc

          Destination Link Address (LLC)  0060b007fab07c
          Destination X.25 Address

          Metric                          0

                    SAVE                               CANCEL
Test
This example shows an incoming X.25 call from a X.25 terminal to the server in the central site.

The syslog messages from the X8500 can be displayed using the SNMP command "debug all&":

x8500:> debug all&
01:46:35 DEBUG/PPP: dialin from <911333333> to local number <85555> (8/5)
01:46:35 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 recv ISDN SETUP sig=0805 loc=85555 rem=85555
01:46:35 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 send ISDN CONNECT
01:46:36 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 accept layer 2 connect
01:46:36 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 recv RESTART cause=0
01:46:36 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 send RESTART CONFIRM 555 fac= cud=
01:46:36 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 vc=0015 recv CALL 0101->85555 fac= cud=
01:46:36 DEBUG/X.25: ifc=00101 addr=00:60:b0:07:fa:b0:7c vc=0001 send CALL 0101->0101 fac=42:08:08:43:04:04:00:0f:c9:03:04:06:01 cud=
...
01:46:36 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 vc=0015 recv CLEAR CONFIRM
01:46:36 DEBUG/X.25: ifc=00101 addr=00:60:b0:07:fa:b0:7c vc=0001 send CLEAR CONFIRM
01:46:36 INFO/ACCT: X25: 03.01.2003/01:46:36,1,0101,85555,0,0,0,0,00,F5
01:46:36 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 TIMEOUT
01:46:36 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 disconnecting layer 2
01:46:36 DEBUG/X.25: ifc=27001 addr=38:35:35:35:35 send ISDN RELEASE
01:46:36 INFO/ACCT: ISDN: 03.01.2003,01:46:35,01:46:36,1,48,63,8,9,,O,911333333,85555,8/5,90,0,X.25
01:46:36 DEBUG/ISDN: stack 1: disconnect cause: normal call clearing (0x90)
x8500:>

The command "ifstat" shows statistical values of the used interfaces:

x8500:> ifstat
Index  Descr        Type Mtu  Speed St Ipkts   Ies Opkts   Oes PhyAddr/ChgTime
...
000100 en0-1        eth  1500   10M up 70      0   1       0   00:a0:f9:02:a5:b2
000101 en0-1-llc    eth  1496   10M up 0       0   1453    0   00:a0:f9:02:a5:b2
...
027001 Filiale           othr 4103   64K up 684     0   456     0     0 00:00:07
  total: 13
x8500:>

It is also possible to display active ISDN and X.25 connections via the "Setup Tool":

ISDN Monitor
X8500 Setup Tool                                     BinTec Communications AG
[MONITOR][ISDN DETAILS]: ISDN Monitor - Details                      x8500
_______________________________________________________________________________

Remote Number: 911333333                    Direction: in     State:

  Cause           (0x90) normal call clearing
  Local Cause     (0x0)
  Info

  Local Number    85555
  Dispatch Item   X.25 over ISDN

  Stack           1
  Channel         B2
  Charging Info

  SIN             x25_services

 EXIT
_______________________________________________________________________________
       (c)alls         (h)istory         (d)etails        (s)tatistics
X.25 Monitor
X8500 Setup Tool                                     BinTec Communications AG
[MONITOR][X.25 DETAILS]: X.25 Monitor - Details                      x8500
_______________________________________________________________________________

  Clear Cause  (0x00)                 Clear Diag 
  Proto ID     0                      State

  Source:
     Interface      Filiale
     VC Number      15
     X.25 Address   0101
     Link Address   3835353535

  Destination:
     Interface      en0-1-llc
     VC Number      1
     X.25 Address   85555
     Link Address   0060b007fab07c

  Packet Size (In/Out)   256/256      Window Size (In/Out)  4/4
  EXIT
_______________________________________________________________________________
       (c)alls         (h)istory         (d)etails        (s)tatistics
rh

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