SL-100 Web Log

IBN Customer Groups

January 28th-February 10th, 2024

IBN stands for Integrated Business Network. This feature on the DMS-100 family of switches is also known as Meridian Digital Centrex (MDC). Centrex on the DMS-100 is quite capable and contains many of the same features as their Meridian 1 PBX line (with some differences obviously).

Additionally Residential Enhanced Services (RES) is based on and tied in with IBN. RES expands the featureset available on otherwise normal POTS lines like 1FR and such.

There are a couple training manuals that I've scanned which cover the basics of IBN translations and common features pretty extensively. Those are Course 0500 and Course 0502.

The university who owned my SL-100 originally were using exclusively IBN for all of their lines and systems, as is normally the case for an SL-100. I started by setting up lines using the POTS line classes, but I needed an IBN customer group to support MMCONFs and it seemed like a good time to cover IBN lines as well.

Customer groups are created in CUSTENG:

        CUSTNAME ADNUM NONCOS NOIBNTMT CONSOLES   DOMAIN GROUPID
                                                                     OPTIONS
----------------------------------------------------------------------------
        SHADYTEL     1     10        0        N  PUBLIC        0
                                                                           $

• CUSTNAME - The name of the customer group.
• ADNUM - A unique number assigned to the group. Values above 4080 are reserved for system-defined customer groups which cannot be created or deleted.
• NONCOS - Number of NCOSes. NCOSes are used to determine usage restrictions for trunk groups and subscribers.
• NOIBNTMT - Number of IBN treatments. Used for call treatments specific to this IBN customer group.
• CONSOLES - Whether or not the customer supports attendant consoles. If you select NO here, this causes the DMS to internally assign a number above 256 for the customer group, which is fine, except that it causes an issue if your CUSTOMER_GROUP_IBNGRP_OM_COUNT parameter in OFCENG is too low, which can only be changed after executing the RWOK ON command.
• DOMAIN - Defines whether the customer group is PUBLIC, PRIVATE, or FAMILY which determines how calls entering and leaving the customer group function.
• GROUPID - A unique ID assigned to the group for AMA and SMDR (billing) purposes.
• OPTIONS - Various options related to special features and restrictions on the customer group.

Before we can continue with filling in CUSTHEAD, we'll have to set up a translator. Translators determine how the dialplan of the customer group is set up. We start in XLANAME:

 XLANAME
                                                                     DEFAULT
MAXDIG
----------------------------------------------------------------------------
   STXLA
                                                                           $
     9

• XLANAME - The name of the translator.
• DEFAULT - Specifies a default translator to use if there is no result in IBNXLA.
• MAXDIG - Chooses the maximum dialable digit between 9, C and F. Options other than 9 are used in Australia.

We'll finish with the translator later, for now we have enough to do some more customer group datafill in CUSTHEAD.

       CUSTNAME CUSTXLA DGCOLNM IDIGCOL
                                                                     OPTIONS
----------------------------------------------------------------------------
       SHADYTEL   STXLA    NDGT     NIL
                          (    VACTRMT  0) (    EXTNCOS   0) (   SUPERCNF )$

• CUSTNAME - Name of the customer group.
• CUSTXLA - Chooses the default translator to use for this customer group.
• DGCOLNM - Chooses a digit collection scheme to be used based on the dialplan of the customer group.
• IDIGCOL - Digit collection for internation switches.
• OPTIONS - Specifies various options for the customer group. There are a lot of possible options for various features and MDC capabilities, default values, that sort of thing. VACTRMT specifies the treatment for vacant numbers to use from IBNTREAT, and I believe this parameter is applied by default. EXTNCOS specifies the NCOS assigned to calls originating from outside the customer group, and I believe this is also a default value. SUPERCNF enables larger conference sizes in MMCONF.

The translator gets datafilled in IBNXLA:

                        KEY
                                                                      RESULT
----------------------------------------------------------------------------
   STXLA                 10
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                 11
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                120
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                121
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1220
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1221
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1222
NET N N 0 N POTS N Y DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $

   STXLA               1223
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1224
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1225
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1226
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1227
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1228
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA               1229
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $

   STXLA                123
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                124
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                125
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                126
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                127
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                128
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                129
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                 13
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                 14
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                 15
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                 16
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                 17
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                 18
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $
 
   STXLA                 19
NET N N 0 N POTS N N DOD N 0 222_POTS_0 NLCA_NILLA_0 NONE $

Translators can get pretty complicated and it's best if you refer to the data schema manuals and training materials. In this example, I've built out the translator basically do 1+10d dialing just the same as it would be on a POTS line. I had to call out 1222 more specifically as I'm considering these calls to be inside the customer group and needed to change a flag for that reason.

The NET selector basically lets us run our call through normal translations via a line attribute. Here, I've reused the same 1FR that has been defined since I don't need any differences, but normally you would set up separate IBN line attributes.

We need to define at least one NCOS, done in table NCOS:

        CUSTGRP  NCOS   NCOSNAME  LSC  TRAFSNO                       OPTIONS
----------------------------------------------------------------------------
       SHADYTEL     0     NCOS0     1        0                             $

• CUSTGRP - The name of the customer group.
• NCOS - The number of the NCOS.
• NCOSNAME - A name for the NCOS.
• LSC - The line screening code to assign for the NCOS. I'll talk about this more briefly below.
• TRAFSNO - Traffic separation number.
• OPTIONS - An NCOS lets you specific various options relating to what types of calls can be placed and how they get place. Some of the most common options will be to add pretranslations that override the normal translators toeither allow or block certain call types.

A quick note on line screening codes: this ONLY takes effect, as far as I can tell, for LINES inside the customer group. If the call is from outside the customer group, or if the call comes from a trunk (even if it's 'in' the customer group), the LSC will be 0 regardless of the setting here and regardless of the setting for EXTNCOS or elsewhere. If the system is going to force us into that behavior, then we might as well use it and consider LSC 0 to be the 'trunks and external calls' LSC, and assign out lines to anything other than 0. For this reason, I've used 1 here, knowing that it will not apply to trunks and external calls, but will apply to my in-group lines.

While's we're talking about it, LSC is checked against entries in table LSCFLAGS when terminating to certain destinations. If the LSC appears in the LSCFLAGS list for that destination, then the call is allowed and denied otherwise.

KEY                                                                 LSCFLAGL
----------------------------------------------------------------------------
  0    (B0) (B1) (B2) (B3) (B4) (B5) (B6) (B7) (B8) (B9) (B10) (B11) (B12)
       (B13) (B14) (B15) (B16) (B17) (B18) (B19) (B20) (B21) (B22) (B23)
       (B24) (B25) (B26) (B27) (B28) (B29) (B30) (B31) $

The simple example above includes all LSCs and does not block any calls.

We can also direct certain ISDN trunk calls through the IBN translations instead of the normal POTS translations in LTCALLS.

            LTID                                                 XLARTSEL
                                                                     OPTIONS
----------------------------------------------------------------------------
 PRI    1    PVT XLAIBN   0 222_POTS_0 NLCA_NILLA_0        SHADYTEL 0   0
                                                                           $

This entry makes it so that ISDN calls coming in with the 'private' number plan indicator (NPI) will go through customer group translations instead. In this simple way, we can effectively specify whether a call is internal to (private) or external to (public) the customer group. ISDN and public NPIs are considered both to be public.

There are more advanced call switches that can be done in LTCALLS but the DMS uses the network specific facility IE (NSF IE) but my Cisco ISR doesn't have any capability to set the NSF IE, so all I have available are the NPIs.

It's also worth noting that NI-2 on the DMS-100 doesn't support the private NPI, so you must use NTNAPRI instead to use that option.

At this point, you can now create IBN lines in SERVORD using the IBN line type. Since IBN lines don't operate on the POTS translations directly, we don't have to create a specific line attribute for them.