GTE Omni Si Database Technical Practices Issue 1 Manual

							File Input/Output
Packet 
Devic a
Handler Software
Asynchronous
Device 
Handler/APM
X.25 Device
Handler/SPM
Pseudo Packet
Device 
Handler/ADMP
SW 5210TL-130500-7001
35.8 The ADMP file system interface subsystem, known as
FIOS, provides an interface for the application tasks running on
the ADMP-C processor to perform input and output operations
on the disk subsystem. It receives the input/output requests from
the application task, transforms them into file control transaction
blocks, and relays them to the file management system
processor across the 
SASI bus. A file control transaction block
contains all information necessary for the file management
system processor to execute the 
input/output operation. As each
request is completed, the result of the operation is returned to the
application task, again via FIOS. Data passing between the
application tasks and the file management system is also
transmitted via FIOS.
35.9 Packet device handler software interfaces with the
customer device and the PD-200 Data System and provides the
protocol service necessary to support the devices.
35.10 The asynchronous device handier software provides an
interface with asynchronous data devices. Both DTE and DCE
interfaces are supported. The asynchronous device handler
resides in an APM card and provides an X.3 PAD function. This
includes asynchronous devices to/from X.25 protocol translation
and flow control.
35.11 The X.25 device handler software provides an X.25
interface. It resides on an SPM card and supports interfaces to
X.25 
DTEs and X.25 PDNs (Public Data Networks). LAPB (Link
Access Procedure Balance) is supported with HDLC framing.
35.12 The pseudo packet device handler is the ADMP
component 
whit? provides an X.25 packet level interface
between the administrative software and the external user to
effect a data call. The pseudo packet device handler is compile
time configurable to handle N logical channels as either
outbound only or two-way. The pseudo packet device handler
acts as a slave to the administrative software in the ADMP,
allowing it to change pseudo packet device handler internal call
states via pseudo packet device handler-supplied utilities.
8/87s-343 
						

							TL-130500-1001
Data Call-Processing 
Software35.13 Call processing and switching refers to the setting up and
tearing down of packet-switched data calls. This does not
include voice or other circuit-switched data call setups. These
calls may be any combination of X.25 end-point, asynchronous
packet assembler/disassembler calls, and/or connections to or
from the administrative ports built into the ADMP card. (These
administrative ports are known as pseudo packet device
handlers.) Call-processing software consists of data call
processing, which resides on a 
UCWDCP card, and packet
device handling, which resides in the APM or SPM. The switch
and command handler are part of the data call-processing
software. The asynchronous packet assembler/disassembler
(residing in the APM) or the X.25 device handler (residing in the
SPM) are examples of pseudo packet device handlers. The
switch, command handler, pseudo packet device handler, and
other administrative software communicate with each other by
using a set of well defined messages.
Administrative,35.14 Administration, control, and maintenance software
Control, andincludes the following utility software components:
Maintenance
Software
0 DMD (Device Message Distributor).
6 ERMA (Event Report Message Administrator).
0 UI (User Interface).
0 TED (Table Editor).
0 MAID (Maintenance and Interactive Diagnostics).
e FUTIL (File Utility).
8 REAPER (Record Account Processing Event Records).
8 DEAR (Dump Event and Accounting Records).
@ Loader.
0 CHANDLER (CEC Handler).
@ ADMPINIT (ADMP Initialization).
DMD (Device Message35.15 The DMD (Device Message Distributor) knows the origin
Distributor)of a message and to which process to send it. Messages
originating from the CEC (via PECLINK) or from data devices (via
NETLINK, SUPERLINK) are distributed to the correct receiving
process on the ADMP.
ERMA (Event Repot-t35.16 ERMA is the event report message administrator of the
MessageADMP. This ADMP function receives and processes events from
Administrator)the data system devices. Event messages are generated from a
device for many reasons, such as device malfunctioning, certain
error condition reached, or garbled communications. ERMA is
responsible for acting on events received by the ADMP. ERMA
acts on the event by executing the appropriate primitives. These
primitives may record the event as a printable message or as an
ADMP statistic. The primitive may initiate another event due to
threshold overflow or other internal conditions on the ADMP.
s-344
8167SVR 5210 
						

							UI (User Interface)
TED (Table Editor)
Data
Recent Change
MAID (Maintenance AndInteractive
Diagnostics)
FUTIL (File Utility)
REAPER (RecordAccount Processing
Event 
Escords)
DEAR {Dump Eventand Accounting
Records)
SW 5210TL-130500-I 
00135.17 The 
UI (User Interface) function of the ADMP is designed
to perform menu presentation conventions for the other
applications. It is the job of the UI to present menus to the user,
screen and check data entered by users, perform security
checking, and transmit finished data structures to applications.
35.18 The TED (Table Editor) function of the ADMP allows users
to dynamically view and optionally change the contents of many
of the ADMP and device tables. TED deals in record structures,
with menus designed to present the table data in user-readable
form. TED will access a copy of a table, interact through the 
UIwith the user to update the table, and then return the updated
copy to disk, to an application, to a data system device, or to
ADMP memory. The 
FIOS interface of TED is for updating tables
to the disk.
35.19 The MAID (Maintenance and Interactive Diagnostics)
function of the ADMP performs interactive maintenance functions
beyond the existing CEC maintenance capabilities. The MAID is
designed to interactively perform status read operations upon
user demand. Some of these functions include 
loopback testing,
taking down a call or an X.25 
fine, changing data set signals,
viewing data system configuration 
and/or device status, etc.
Since a debug code will exist in the ROMs of the data system
devices, a special function of the MAID is to provide interactive
debugging to users. A network debugging tool allows users to
directly communicate with the ROM of a data device.
35.20 The FUTIL (File Utility) function of the 
ADMP allows users
to copy disk files, interactively change the names of files, dump.
delete, or perform disk maintenance functions.
35.21 The REAPER (Record Account Processing Event
Records) accepts call 
accounting records and stores them on
disk. This is performed in a similar manner to the event handler
(ERMA), where records are stored until they are forwarded.
35.22 The DEAR (Dump Event and Accounting Records) is the
event and accounting record dumping mechanism. The DEAR is
designed to accept an incoming X.25 call to dump records, or
make an outgoing X.25 call to dump records to any terminal
connected to the data system or to the RS 232-terminal. The
DEAR operates by sequentially reading the event tracking file
written by ERMA, and/or by reading the accounting tracking file
written by the REAPER. The DEAR is the mechanism by which
events and/or accounting records are forwarded to various
devices.
Em7s-345 
						

							TL-130500-1001Loader35.23 The Loa x is responsible for initializing and loading any
data system 
de,;lce which requires code and/or tables. The
loader accesses the disk through 
FIOS to read code or data
records and transmits them to the device being loaded. Once a
device is loaded, the success or failure of the load is reported to
the ERMA event handler.
CHANDLER35.24 The CHANDLER (CEC Handler) is an ADMP function
(CEC Handler)which is solely responsible for dealing with requests from the
CEC. The CEC may instruct the ADMP to make dynamic
changes to the data system configuration or status, add or delete
cards or lines, put a card or line out of service, load a device, or
any other recent change or maintenance function. The
CHANDLER is responsible for processing these requests and
sending appropriate messages to other functions of the ADMP
(such as the LOADER or ERMA).
ADMPINIT35.25 The ADMP Initialization is a complex function
(ADMP Initialization)which allows the ADMP to boot from the disk and begin
processing. The ADMP ROM (Read-Only Memory) is
responsible for loading the operational code. The operational
code initialization step is responsible for starting all processes,
and for initializing static data areas and files.
S-3468l87SVR 5210 
						

							TL-130500-I 001Transmission36.0 This section provides information on trunk transmission
And Loss Plansand loss plans as they apply to the system. The VNLP (Via Net
Loss Plan) and the FLP (Fixed Loss Plan) are described and
trunk loss objectives and digital pad switching rules are given.
All trunks on a system should be designed for either VNLP or
FLP and must conform to certain trunk loss constraints.
The 
OMNI SI is a time-divided pulse-code-modulated system
that can be operated as main, tandem, or satellite PABX within
a TTTN (Tandem Tie Trunk Network), or as a main, satellite, or
Class SS3 PABX in a SSN (Switched Services Network).
Switching PADS36.1 To provide the correct transmission interface parameters,
the 
ONMI SI PABXs are arranged to provide pad switching.
Pad switching is digitally provided under software control.
This allows a four-wire Tie trunk to be designated a 
non-tandem, tandem, or intertandem by changing the data base.
The digital pad values are 0, 2, 3, or 5 
dB, depending on the
application. The values of the pads that are digitally stored
are subtracted from the signal in a pulse code modulated
format to arrive at the padded value.
Via Net36.2 The VNLP was developed in the 1950s to provide a method
Loss Planof controlling return loss by determining circuit loss based on
the type of facility and circuit length. VNL (Via Net Loss) is more
precisely expressed in its component parts: (VNL factor) x
(facility length in miles) + 
0,4 dB. The VNL factor is a constant
associated with the type of facility assigned to the circuit. The
0.4 
dB is a factor added to account for variation in circuit loss
due to changes in temperature and other factors. Refer to
Section 875-000-071 for further information on determining
VNL for various circuits.
When a digital PABX is intended to replace an existing analog
PABX, due to growth or feature enhancements, or a new PABX is
being installed to operate under the VNLP, no special treatment
of trunks or facilities is required, assuming the trunks or facilities
are properly engineered for any other type of PABX. The VNLP
should not be used if the system is installed with a direct 
Tl-type interface or if a direct Tl-type interface will be used in the
future.
Tandem and intertandem Tie trunks should be assigned to
four-wire facilities from PABX to PABX. If a satellite Tie trunk
is to be switched to a tandem or inter-tandem Tie trunk, the
satellite Tie trunk should also use four-wire facilities. It is also
recommended that class 4 WATS circuits use four-wire facilities
if possible.
SW 52108187s-347 
						

							TL-130500-1001
When a Tie trunk is switched to a CO trunk that has less than 2dB of loss, the PABX can be programmed to switch in a 2 dBpad to ensure good balance. A pad should not be provided
when the CO trunk ICL (Inserted Connection Loss) exceeds 2 
dB.
Because pad control is part of the data base, the fact that the
PABXCO facility is short (less than 2 dB) should be noted when
ordering a PABX.
The ICL objectives for the VNL plan are given in Table 36.1.
These are established network objectives and are independent
of the type of PABX or facilities used.
In PABX applications, regardless of whether the VNLP or FLP
is implemented, a 5 
dB digital pad is inserted on line-to-linecalls. Figure 36.1 shows the connection. A typical line-to-CO
trunk connection under the VNLP is shown in Figure 36.2. No
digital pad is inserted and the connection loss is the facility
loss plus 0.5 
dB across the PABX, Figure 36.3 shows a line-
to-intertandem Tie trunk using the VNLP and Figure 36.4shows a line-to-nontandem Tie trunk connection. In Figures
36.1 through 36.4, the pads are labeled A and B to allowcorrelation between the figures and Table 36.2. Table 36.2
lists the pad switching rules for a PABX operating under the
VNLP.
Fixed Loss36.3 When a direct Tl-type interface is used to connect circuits
Planin a system, it is necessary to use the FLP to provide correct
circuit interface levels. The FLP can also be used when all
facilities are analog.To properly integrate into the North American telephone
network, a transmission plan such as the FLP must conform
to the following constraints:
1. EML (Expected Measured Loss) and ICL must be symmetrical;that is, they must be equal regardless of transmission
direction.
2. The 
2-dB TLP (Test Level Point) at the outgoing side ofanalog toll switches and the 
0-dB TLP at end offices must
be retained.3. The input and output 
TLPs of carrier facilities (-16 TLP and
+ 7 TLP) must be retained.
4. Existing lineup and test procedures for D-type channel banks
must be retained.5. Loss, noise, and echo grades of service should be brought as
close to optimum as possible to maintain or improve
transmission performance perceived by the network user.
S-348
8187SVR 5210 
						

							TL-130500-1001
000-5-5.5
OMNI PABX
B PAD
----me------------
0.5
~~~~~~~~~~-----_-_--_A PAD
-5.5 -5
000
Figure 36.1Line-to-Line Call (VNLP or FLP)0 0
-0.5
OMNI PABX
B PAD
-2.9
-3.2
Class5 CO
-3.2-2.7 -2.7-0.30
SW 5210
Figure 36.2
Line to CO Trunk Call (VNLP)
8l87s-349 
						

							TL-130500-100100-2.0-2.5 -16+7 -2.8-4.8
OMNI PABX
Main PABX Office
LB PAD 0.5
’ PT Carrier ‘Carrier
-------_-16 
-fLPoint i250.5APADVNL = 0.8
-4.8-4.3-2.3 -2.3-2.3 +7 -16 -20
Figure 36.3Line to Intertandem Tie Trunk Call (VNLP)
00
-2-2.5 -6.1-1.4-5
OMNI PABX
Class 5 COPABX
\B PAD 0.5
’ 24 ’ r 24-
--/“y-J& ;ggkilofeet
22H882 
dB Trunk!cablecable
Card
:-------
c
++-3.6 
dB 3.6 dB-loss
loss
0.5A PADtvoice
frequency
repeater
-5.0-4.5-2.5 -2.5-2.5 + 1.1 -3.6
-.^-a . . -.__. -. - . A . . ,.,mm. -\Figure 36.4Line to Nonfanaem 1 le 1 runK Lali (vNLiq
8187SW 5210 
						

							SVR 5210TL-4 30500-l 001
The FLP was developed specifically for systems where a direct
digital interface to a digital trunk facility is provided. A direct
digital trunk interface eliminates the toll terminating equipment
(pads, four-wire terminating sets, and voice frequency
repeaters) that is normally adjusted to provide the proper ICL on
the receive transmission path of a PABX. A method of providing
the required loss to the PABX was required and switchable pads
provided the most reasonable solution. With different ranges of
ICLs for the various trunk groups (Tie trunks and CO trunks) and
the variation of VNL based on type of facility and circuit length,
the number of pads required and the software control to insert
the proper pad value became prohibitive. The FLP was chosen
to eliminate the ICL variations caused by the differences in 
VNLs.The values chosen for CO and Tie trunks were a compromise
that would not degrade typical connections beyond allowable
limits nor require additional line treatment equipment, such as
voice frequency repeaters on analog facilities that were
acceptable for analog systems. It should be noted that a VNL
trunk cannot be switched to an FLP trunk because improper
levels and lack of symmetry would result.
Under the FLP, the center of the system is treated as a zero
reference level point in both directions of transmission. This
results in a symmetrical system with ideal characteristics for
conference calls. Refer to Figures 36.5 through 36.11, which
indicate the symmetry of levels at the mid-switch point.
It is virtually impossible to follow the VNLP when using digital
or combination trunks. Trunk losses can be changed, but this
usually results in violations of constraints listed in paragraph
36.3.An FLP, by necessity, increases the loss of some trunks that
would be assigned to low-loss facilities. An example would be
a PABX located a few thousand feet from a CO that had a Tie
trunk group assigned to a direct digital interface. The loss from
the PABX to the CO would normally be approximately 0.5 
dB.Under the FLP, it would be 3.5 
dB. On the other hand, long
trunks such as cross-country Tie trunks are limited to the fixed
loss ICL, 5.5 
dB, rather than the ICL determined by VNL + 2s +
2s (2s denotes a 2 dB switchable pad), which could be greater
than 6 
dB. Table 36.3 lists the fixed loss objectives and pad
switching rules for a system.
8/Ws-351 
						

							TL-130500-1001
Table 36.1ICL Objectives for PABX Circuits (VNLCOMMONSHORT
CIRCUITS
LANGUAGEHUAL ICL
CODE
NWLine on premises
PXLine off premises
OSPABX-CO trunk
TK
Foreign exchange trunk
FTUpto4.0
up to 3.53.5Satellite Tie trunk
Nontandem PABX Tie trunkSAVNL + 
2s + 2sTLVNL + 
2s +2STandem PABX Tie trunk
inter-tandem PABX Tie trunk
Incoming class 5 WATS trunk
Outgoing class 5 WATS trunk
Outgoing class 4 WATS trunkTAVNL + 
2s +2-SITVNL + 
2s +2SWl(5)up to 3.5
WS(5)up to 3.5
WS(4) 4.5
Design)
-1VNL + 4.0
IVNL + 
2s + 2sIVNL + 
2s + 2sIVNL 
+4.0INOTE: 
2s denotes a 2-dB switchable pad.
The FLP trunk cards provide for adjustments to be made on
any remaining analog trunks terminating on the system. These
adjustments, essentially similar to voice frequency attenuation
selection in channel units, compensate for the analog facility
loss.
On two-wire trunks, the level change is made by changing
strapping or strapping resistors in the trunk units. This change
is indicated by the variable attenuators and amplifiers in Figures
36.5, 36.6, and 36.7. The FLP two-wire trunk cards may be
used for both the VNLP and the FLP. Certain trunk cards are
designed for the VNLP only and do not provide the adjustments
required for the FLP. If there is a possibility that the system will
change in the future from the VNLP to the FLP because a direct
Tl-type interface will be used, the FLP trunk cards (applicable
to both plans) should be installed initially.
S-352
8187SVR 5210