DMS-100 Lines Subsystem Overview

Functional Description

The lines subsystem pertains to the thousands of subscriber lines that reside outside the DMS-100 switch and connect to the switch through Line Cards (LC), which reside within Peripheral Modules (PM).  Every line connects to the DMS-100 switch through a LC.

On one end of the lines subsystem are telephones or other subscriber equipment.  Coming out of the telephone are two wires, tip (ground) and ring (-48 VDC), which together form a telephone line.  When a subscriber speaks, sound waves are converted by the telephone transmitter into electronic analog signals that travel over the telephone line until they reach a Central Office (CO).  At the CO, the line connects to a Line Concentrating Module (LCM) or other appropriate PM that houses the LC associated exclusively with that line.

Subscriber Lines

A subscriber line consists of a:

Subscriber lines may be connected directly to peripherals in the main switch called the host, or to remotely located PMs.  Remote PMs that are part of the DMS-100 family may be Remote Line Modules (RLM) or Remote Line Concentrating Modules (RLCM).  Additional information concerning these remote units is in Peripheral Modules, NTP 297-1001-103.  Remote PMs may also be part of compatible subscriber carriers such as DMS-1 and SLC-96.  Additional information may be found in the Bell Communication Research Incorporated Technical Reference, TR-TSY-00008.  Subscriber lines may also be connected to a Remote Digital Terminal (RDT) which is a remote facility that multiplexes the signals onto an optical transmission facility.  The RDT described in this document is the S/DMS AccessNode Remote Fiber Terminal (RFT).

Each type of LCD accepts a variety of line cards for a range of telecommunication services.  The services that are provided, and the sets used, are as follows:

The Universal Edge 9000 (UEN) provides concentrated support for up to 512 lines (32-line multi circuit line card x 16 line card slots).  Two high-speed, point-to-point serial buses, the Time Division Muliplex (TDM) and Grace Local Area Network (GLAN) buses, provide an interface between the 16 line card slots and the NTKX06AA.

Note:  The term "downstream" indicates the direction of flow from the controlling LGC, LTC, or RCC2 to each line circuit.  The term "upstream" indicates the direction from each line circuit to the controlling LGC, LTC, or RCC2.

Line Card Description

Line cards terminate the lines subsystem inside the DMS-100 host office.  The lines' analog signals are converted into digital signals by the LC, combined with other lines' signals by the LCM and are sent into the network.  The network determines a route for the speech signals and then sends them out to their respective destinations.  The routed signals are sent along the telephone line of the person on the other end of the conversation and converted from analog signals back into sound waves by the telephone receiver.

Line card types vary according to the services that use them and the type of equipment in which they are mounted.  Line cards are mounted in a LCD that may be located at:

The "world" line card is a software programmable line card, which means that it can be datafilled for use in any market.  The two types of world line card include Type A (NT6X17BA) and Type B (NT6X18BA).

The UE9000 DMS-100 lines are in Line Subgroups (LSG) that have the physical boundary of a single line card.  The LSGs are equivalent to XLCM drawers (LSG).  In the XLCM, each physical drawer contains two LSGs.

Table 1 lists the types of line cards used with the DMS-100 switch.

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Table 1 - Line Card Types

LC Mounting      Product             Lines Per
Equipment        Engineering Code    Card        Description
-----------------------------------------------------------------------------------------
DMS-1R RCT       QPP 405             4           Single party.
                 QPP 409             2           Universal coin.  (Note 1)
                 QPP 440             4           Frequency selective signaling.
		 QPP 442             2           Post pay coin.  (Note 1)
		 QPP 445             4           Superimposed signaling.
		 QPP 541             4           Frequency selective signaling.
-----------------------------------------------------------------------------------------
DMS-1 RCU        NT3A10AA/AB/HA/HB   2           Single-party line card in a NT3A06AA/BA
                                                 Line Card Carrier (LCC).

Note: All Remote Carrier Urban (RCU) line cards are placed 
      in a LCC.  Each LCC has a capacity of four line 
      cards, and it is placed in one RCU slot.

      Multi-Party Divided Ringing (MPDR) line card in an 
      NT3A19AA LCC

                 NT3A10AB/AC/HA/HB   2           Frequency Selective Ringing (FSR) line 
		                                 card in a NT3A07AA/BA LCC.
                 NT3A12AB            2           Two-wire FX, PBX trunk LS/GS line card 
		                                 in a NT3A11AB LCC.
		 NT3A13AB            2           Two-wire OPS line card in a NT3A11BA LCC.
		 NT3A13AC            2           Two-wire OPS line card in a NT3A11CA LCC.
		 NT7A20AA            1           Four-wire line card in a NT3A11BA/CA LCC.
		 NT7A21AA            1           Four-wire line card in a NT3A11BA/CA LCC.
		 NT7A22AA            1           Four-wire line card in an NT3A11BA/CA LCC
		 NT7A23AA            1           Four-wire line card in an NT3A11BA/CA LCC
		 NT7A25AA            1           Enhanced two-wire line card in a 
		                                 NT3A11BA/CA LCC.
		 NT7A26AA            1           Enhanced two-wire line card in a 
		                                 NT3A11BA/CA LCC.
		 NT7A27AA            1           Enhanced two-wire line card in a 
		                                 NT3A11BA/CA LCC.
		 NT7A33AA            1           MBS line card in a NT3A11CA LCC.
-----------------------------------------------------------------------------------------
International    NT6X17BA            1           Type A world line card with profile
LCM (ILCM)                                       downloading capability.  (Note 2)
                 NT6X18BA            1           Type B world line card with profile 
		                                 downloading capability.  (Note 3)
                 NT6X21AA            1           Business set line card.  (Note 12)
		 NT6X21AB/AC/AD      1           2.8 mile business set line card.  (Note 12)
		 NT6X21CA            1           Universal Modular P-Phone Line Card (UMPLC).  
		                                 (Note 16)
		 NT6X93AA/CA/EA      1           International Type A line card used on 
		                                 analog facilities for single- and two-party 
						 flat rate service.  (Notes 4 & 5)
		 NT6X94AA/CA         1           International Type B line card similar 
		                                 to NT6X93AA/CA but used for four-party 
						 flat rate and coin service.  (Notes 4 to 6)
                 NT6X94AB            1           International Type B line card used for 
		                                 single-party, PBX, and coin subscribers.  
						 (Notes 4 to 6)
----------------------------------------------------------------------------------------
LM Drawer        NT2X17AB/AC         1           Type A line card used on analog facilities 
                                                 for single and two-party flat rate service.
                 NT2X17AD            1           Type A line card similar to NT2X17AB/AC, 
		                                 used in applications requiring 20 dB idle 
						 channel noise.
		 NT2X18AC            1           An earlier vintage of NT2X18AE.
		 NT2X18AD            1           Type B line card similar to NT2X18AE but 
		                                 equipped with +48 VDC for additional coin 
						 features.  (Note 7)
		 NT2X18AE            1           Type B line card similar to NT2X17AB but 
		                                 used for multiparty flat rate, coin, and 
						 ground start service.
-----------------------------------------------------------------------------------------
LCM Drawer       NT6X17AA            1           Type A line card used on analog facilities 
                                                 for singleand two-party flat rate service.
                 NT6X17AB            1           Type A line card similar to NT6X17AA but 
		                                 used where low noise is required.  (Note 8)
		 NT6X17BA            1           Type A world line card with profile 
		                                 downloading capability.  (Note 2)
		 NT6X18AA            1           Type B line card similar to NT6X17AA but 
		                                 used for four-party flat rate and coin service.
		 NT6X18AB            1           Type B line card similar to NT6X18AA but
		                                 equipped with +48 VDC for additional coin 
						 features.  (Note 9)
		 NT6X18BA            1           Type B world line card with profile 
		                                 downloading capability.  (Note 3)
		 NT6X19AA            1           Message waiting line card.  (Note 10)
		 NT6X21AA            1           Business set line card.  (Note 11)
		 NT6X21AB/AC         1           2.8 mile business set line card.  (Note 11)
		 NT6X21BC            1           U.K. business set line card.
		 NT6X21CA            1           Universal Modular P-Phone Line Card (UMPLC). 
		                                 (Note 16)
		 NT6X33AA            1           General Use Line (GUL) card, providing 
		                                 single-party voice and signaling on an 
						 analog line.
		 NT6X71AA            1           Data line card.
		 NT6X71AB            1           Similar to NT6X71AA data line card, 
		                                 with profile downloading capability.
		 NT6X71BA            1           Single slot version of the NT6X71AB data line
		                                 card, with profile downloading capability.
		 NT6X76AA/AC         1           Data asynchronous interface line card.  (Note 12)
		 NT6X99AA            1           Datapath BERT card.  (Notes 13 and 14)
-----------------------------------------------------------------------------------------
S/DMS            NT4K67AB            1           2-wire station line card.
AccessNode       NT4K68AA            1           2-wire office line card.
	         NT4K69AA            2           4-wire special services line card.
	         NT4K77AA            2           6/8-wire special services line card.
-----------------------------------------------------------------------------------------
LCME             NT6X17AA            1           Type A line card used on analog facilities 
                                                 for singleand two-party flat rate service.
                 NT6X17AB            1           Type A line card similar to NT6X17AA but 
		                                 used where low noise is required.  (Note 8)
            	 NT6X17BA            1           Type A world line card with profile 
		                                 downloading capability.  (Note 2)
		 NT6X18AA            1           Type B line card similar to NT6X17AA but 
		                                 used for four-party flat rate and coin 
						 service.
		 NT6X18AB            1           Type B line card similar to NT6X18AA but 
		                                 equipped with +48 VDC for additional coin 
						 features.  (Note 9)
                 NT6X18BA            1           Type B world line card with profile 
		                                 downloading capability.  (Note 3)
		 NT6X19AA            1           Message waiting line card.  (Note 10)
		 NT6X21AA            1           Business set line card.  (Note 11)
		 NT6X21AB/AC/AD      1           2.8 mile business set line card.  (Note 11)
		 NT6X21CA            1           Universal Modular P-Phone Line Card (UMPLC). 
		                                 (Note 16)
		 NT6X71BA            1           Single slot version of the NT6X71AB data 
		                                 line card, with profile downloading 
						 capability.
		 NT6X76AA/AC         1           Data asynchronous interface line card. 
		                                 (Note 12)
		 NT6X99AA            1           Datapath BERT card.  (Notes 13 and 14)
-----------------------------------------------------------------------------------------
SLC-96 RCS       SCD 203             2           Single-party.
                 SCD 221             2           Multi-party.
	         SCD 233             1           Coin.  (Note 15)
-----------------------------------------------------------------------------------------
Small Remote     NT6X17BA            1           Type A world line card with profile 
                                                 downloading capability.  (Note 2)
Unit (SRU)       NT6X21BC            1           U.K. business set line card.
                 NT6X71AB            1           Similar to NT6X71AA data line card, 
		                                 with profile downloading capability.
		 NT6X76AC            1           Data asynchronous interface line card.
-----------------------------------------------------------------------------------------
Universal 9000   NTNP50AA            32          POTS 32 multi-circuit line card.
9000 (UEN)       NTNP44AA            4           ADSL DMT 4+4 line card.
-----------------------------------------------------------------------------------------
Note 1: RCT coin line circuit cards are restricted to the first two positions in 
each shelf.  All other RCT line cards may be installed in any card position.

Note 2: The NT6X17BA World line card can emulate the following cards: 
NT6X17AC, NT6X93AA, NT6X93BA, NT6X93CA, NT6X93DA, NT6X93EA, and NT6X98AA.

Note 3: The NT6X18BA World line card can emulate the following cards: 
NT6X18AA, NT6X33AA, NT6X94AB, NT6X94BB, NT6X94CA, and NT6X94DA.


Note 4: The NT6X93 and NT6X94 International line cards are equipped with 
a 600-ohm termination, rather than the 900-ohm termination that is in the NT6X17 
and NT6X18 series line cards.  Further, it uses the A-Law binary coding algorithm 
for converting analog speech path signals to digital signals, rather than the 
Mu-Law algorithm that is used in North American line cards.

Note 5: International line cards are not used in the RLCM.

Note 6: The NT6X94 International line cards require a NT6X95AA metering tone 
card in slot 0 of the odd ILCM drawer.  The tone is output continuously on the 
+48 VDC bus and supplies a physical ILCM drawer.  Because slot 0 is also assigned to 
the NT6X23AA +48 VDC power converter card, these two cards cannot coexist in a physical 
line drawer.

Note 7: All NT2X18AD Type B line cards that are mounted in a line drawer are 
associated with a NT2X03AA +48 VDC power converter card that is located in slot 31 in 
the drawer.

Note 8: The NT6X17AB Type A line card responds to diagnostic tests in the same way 
as the NT6X17AA line card.

Note 9: All NT6X18AB Type B line cards that are mounted in a line drawer may be associated 
with a NT6X23AA +48 VDC power converter card that is located in slots 0 and 16 of the odd numbered 
(upper) line subgroup in the drawer.  A switch on the line card can be operated to control access 
to the +48 VDC supply.

Note 10: All NT6X19AA Message Waiting line cards in a line drawer are associated with a 
NT6X20AA +150 VDC power converter card mounted in slots 0 and 16 of the odd numbered (upper) 
line subgroup in the drawer.

Note 11: The NT6X21AA Meridian Business Set line card is used on loops that are up to 
6,000 feet in length, while the NT6X21AB business set line card is used on loops that are up 
15,000 feet in length.

Note 12: The NT6X76AA/AC Asynchronous Interface line card occupies two vertically 
contiguous slots in the LCM.

Note 13: The NT6X99AA BERT card occupies two vertically contiguous slots in the LCM.

Note 14: Because of the high volume of messaging between the IBERT and the DMS-100 
switch while a BERT test is active, it is recommended that a maximum of one IBERT card be 
provided for each LCM.

Note 15: RCS coin line circuit cards are restricted to the four rightmost line card 
positions in each shelf when DS-1 line facilities are connected one per group (see Figure 7).

Note 16: The NT6X21CA UMPLC replaces the NT6X21AC, NT6X21AD, and NT6X21BC line cards.
-----------------------------------------------------------------------------------------
-End-

The types of LCD that mount line cards at host locations are:

The LCD designed to provide high-density Plain Old Telephone Service (POTS) and Asymmetric Digital Subscriber Loop (ASDL) service is called the Universal Edge 9000 (UEN).  The UEN uses Multi-Circuit Line Cards (MCLC).





The UE9000 DMS-100 shelf contains:

The UE9000 DMS-100 shelf is self-contained and has with the following cards:

The international version of the LCM, called the ILCM, has the same line card capacity as the LCM, although one card position is used by a metering tone card (see Table 1).

The types of LCD that mount line cards that are located remotely from the host are:

The OPM, a cabinet located outdoors, contains the following equipment:

The card capacity of each LCD is shown in Table 2.

            
-----------------------------------------------------------------------------------------
Table 2 - Line Card Capacity by LCD Type

Line Concentrating
Device (LCD)                Capacity
----------------------------------------------------------------------------------------- 
LM                          32 cards per drawer
                            5 drawers per shelf unit
		            4 shelf units per LM
-----------------------------------------------------------------------------------------
LCM                         32 cards per subgroup
                            2 subgroups per drawer
		            5 drawers per shelf unit
		            2 shelf units per LCM
-----------------------------------------------------------------------------------------
LCME                        30 cards per subgroup 
                            2 subgroups per drawer 
		            4 drawers per shelf unit 
		            2 shelf units per LCME
-----------------------------------------------------------------------------------------
RFT                         48 cards per drawer 
                            2 drawers per shelf 
		            7 shelves per RFT
-----------------------------------------------------------------------------------------
RLM                         32 cards per drawer 
                            5 drawers per shelf 
		            4 shelves per RLM
-----------------------------------------------------------------------------------------
RLCM                        32 cards per line subgroup 
                            2 line subgroups per drawer 
		            5 drawers per shelf 
		            2 shelves per RLCM
-----------------------------------------------------------------------------------------
RCT                         8 cards per shelf 
                            8 shelves per RCT 
		            10 RCTs per group
-----------------------------------------------------------------------------------------
RCU                         2 line circuits per line card 
                            4 shelves per RCU with line cards 
		            12-20 Line Card Carriers (LCC) per shelf 
		            4 line cards per LCC
-----------------------------------------------------------------------------------------
RCS                         16 cards per shelf 
                            4 shelves per RCS
-----------------------------------------------------------------------------------------
SRU                         60 cards per drawer 
                            4 drawers 
		            1 shelf per SRU
-----------------------------------------------------------------------------------------
UEN                         16 cards per shelf 
                            4 shelves per Universal Edge Equipment (UEE) frame
-----------------------------------------------------------------------------------------
-End-

Locating a Line Card

The CKTLOC command displays in the work area to the right of the menu area.  The following headers are displayed with menu item 11, and the location of the line card in the control position is displayed under the headers:

The CKTLOC command identifies the physical location of the line card.  This identification is not to be confused with the LEN, discussed in the "LEN Numbering" section, that identifies the location of a line in memory.

In addition displaying the line card location, the CKTLOC command displays the characteristics of the line in the control position.  The following header labels for the characteristics are displayed below the CKTLOC response data:

Note:  The values displayed are those from the line circuit inventory table LNINV.

The paragraphs that follow along with Figure 1 and Figure 2 discuss the CKTLOC command entered for a line that terminates in a DMS-1R RCT and a set of lines that terminate in a SLC-96.

When the CKTLOC command is entered at the LTP level for a line that terminates in a DMS-1R RCT, the format of the display is consistent with other CKTLOC displays, but the interpretation of the CKTLOC information is different.  As shown in Figure 1, there are four Flat Rate (FR) circuits for each DMS-1R RCT line card.  The example in Figure 1 is for a remote subscriber line on a DMS-1R RCT equipped with a QPP405 line card.  The CKTLOC information that is displayed is interpreted as follows:

Figure 1

LTP level-CKTLOC display for RCT line:

When the commands POST and CKTLOC are entered at the LTP level for a set of lines that terminate in a remote concentrator SLC-96 (RCS) the display is in accordance with the example in Figure 2.




























Figure 2

LTP level-CKTLOC display for an RCS line:

The CKTLOC information that is displayed in Figure 2 is interpreted as follows:

This is a redundant identification of the line card shelf to simplify locating the shelf.

LEN Numbering

The Line Equipment Number (LEN) is a group of numbers that describe the location of a line in memory sometimes called the logical location.  They are preceded by a four character CLLI that identifies the site of a remotely located line, or by the characters HOST that identify the line site as the switch location.  The first character of the CLLI of the remotely located line is a letter, while the remaining three characters may be letters or numbers.

The LEN is not to be confused with the circuit locate identification that is used to describe the physical location of a circuit line card in a LCD.

The LEN is formatted as: ff u dd cc

When circuit numbers 00 through 09 are entered as 0 through 9, the system default interprets the unentered first character as 0 and accepts the abbreviated entry of the circuit number.

If the office has a remotely located LCD, and the LM or the LCM are uniquely numbered by site, the CLLI is required before the LEN.  If the LM or LCM numbers are unique to the whole office, then the CLLI is optional.

The remote terminal of a DMS-1 subscriber carrier system is called a Remote Concentrator Terminal (DMS-1R RCT).  The DMS-1R RCT is connected to the host network module through a 1.544 Mb/s digital line and a Subscriber Carrier Module (SCM) that provides an interface with the 2.56 Mb/s digital rate speech link of the DMS-100 switch.  A single SCM can terminate a maximum of six DMS-1R RCTs.

The remote terminal of a SLC-96 subscriber carrier system is called a Remote Concentrator SLC-96 (RCS).  The RCS is connected to the host network through a 1.544 Mb/s digital line and a peripheral module called a SMS that provides an interface with the 2.56 Mb/s digital rate speech link of the DMS-100 switch.

Remote locations that are equipped with these types of subscriber carrier terminals mount line cards in shelf slots rather than in drawer slots.  However, the shelf number is assigned in the dd field of the LEN number to maintain its standard format.  Figure 4 through Figure 8 show the use of the standard LEN format when used with various LCDs.  For all applications except the RCS, the location of the circuit in memory is directly related to the physical location of the line card.  The RCS line card that is part of a specific line circuit may be identified using the mapping diagram shown in Figure 9.  RCS line circuit numbers 24 through 31 are unassigned to simplify the relationship between the logical location and physical location of the line circuit.  Figure 10 shows the arrangement of the shelves and slots in the S/DMS AccessNode RFT which relate to the LEN numbering for RDT lines.  Figure 11 shows the arrangement of the drawers and card slots in the SRU which relate to the LEN numbering for SRU lines.

There is no LEN for a Datapath Loop Extension (DPX) line.  The line's logical location is directly identified with the logical location of the associated trunk circuit in the serving office switch.








































Figure 3

LM and RLM LEN numbering:























Figure 4

LCM and RLCM LEN numbering:























Figure 5

LCME LEN numbering:
























Figure 6

UEN numbering:







Figure 7

DMS-1R RCT LEN numbering:






















Figure 8

RCS (SLC-96) LEN numbering:























Figure 9

RCS (SLC-96) line card mapping:




Figure 10

RFT line card mapping:







Figure 11

SRU LEN numbering: