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Current issue : #24 | Release date : 1989-02-25 | Editor : Taran King
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Phrack World News XXIVKnight Lightning
Title : Control Office Administration Of Enhanced 911 Service
Author : The Eavesdropper
                                ==Phrack Inc.==

                      Volume Two, Issue 24, File 5 of 13

         []                                                        []
         []              Control Office Administration             []
         []              Of Enhanced 911 Services For              []
         []       Special Services And Major Account Centers       []
         []                                                        []
         []                   By The Eavesdropper                  []
         []                                                        []
         []                       March, 1988                      []
         []                                                        []

Description of Service
The control office for Emergency 911 service is assigned in accordance with the
existing standard guidelines to one of the following centers:

     o  Special Services Center (SSC)
     o  Major Accounts Center (MAC)
     o  Serving Test Center (STC)
     o  Toll Control Center (TCC)

The SSC/MAC designation is used in this document interchangeably for any of
these four centers.  The Special Services Centers (SSCs) or Major Account
Centers (MACs) have been designated as the trouble reporting contact for all
E911 customer (PSAP) reported troubles.  Subscribers who have trouble on an
E911 call will continue to contact local repair service (CRSAB) who will refer
the trouble to the SSC/MAC, when appropriate.

Due to the critical nature of E911 service, the control and timely repair of
troubles is demanded.  As the primary E911 customer contact, the SSC/MAC is in
the unique position to monitor the status of the trouble and insure its

System Overview
The number 911 is intended as a nationwide universal telephone number which
provides the public with direct access to a Public Safety Answering Point
(PSAP).  A PSAP is also referred to as an Emergency Service Bureau (ESB).  A
PSAP is an agency or facility which is authorized by a municipality to receive
and respond to police, fire and/or ambulance services.  One or more attendants
are located at the PSAP facilities to receive and handle calls of an emergency
nature in accordance with the local municipal requirements.

An important advantage of E911 emergency service is improved (reduced) response
times for emergency services.  Also close coordination among agencies providing
various emergency services is a valuable capability provided by E911 service.

1A ESS is used as the tandem office for the E911 network to route all 911 calls
to the correct (primary) PSAP designated to serve the calling station.  The
E911 feature was developed primarily to provide routing to the correct PSAP for
all 911 calls.  Selective routing allows a 911 call originated from a
particular station located in a particular district, zone, or town, to be
routed to the primary PSAP designated to serve that customer station regardless
of wire center boundaries.  Thus, selective routing eliminates the problem of
wire center boundaries not coinciding with district or other political

The services available with the E911 feature include:

       Forced Disconnect         Default Routing
       Alternative Routing       Night Service
       Selective Routing         Automatic Number Identification (ANI)
       Selective Transfer        Automatic Location Identification (ALI)

Preservice/Installation Guidelines
When a contract for an E911 system has been signed, it is the responsibility of
Network Marketing to establish an implementation/cutover committee which should
include a representative from the SSC/MAC.  Duties of the E911 Implementation
Team include coordination of all phases of the E911 system deployment and the
formation of an on-going E911 maintenance subcommittee.

Marketing is responsible for providing the following customer specific
information to the SSC/MAC prior to the start of call through testing:

o  All PSAP's (name, address, local contact)
o  All PSAP circuit ID's
o  1004 911 service request including PSAP details on each PSAP
   (1004 Section K, L, M)
o  Network configuration
o  Any vendor information (name, telephone number, equipment)

The SSC/MAC needs to know if the equipment and sets at the PSAP are maintained
by the BOCs, an independent company, or an outside vendor, or any combination.
This information is then entered on the PSAP profile sheets and reviewed
quarterly for changes, additions and deletions.

Marketing will secure the Major Account Number (MAN) and provide this number to
Corporate Communications so that the initial issue of the service orders carry
the MAN and can be tracked by the SSC/MAC via CORDNET.  PSAP circuits are
official services by definition.

All service orders required for the installation of the E911 system should
include the MAN assigned to the city/county which has purchased the system.

In accordance with the basic SSC/MAC strategy for provisioning, the SSC/MAC
will be Overall Control Office (OCO) for all Node to PSAP circuits (official
services) and any other services for this customer.  Training must be scheduled
for all SSC/MAC involved personnel during the pre-service stage of the project.

The E911 Implementation Team will form the on-going maintenance subcommittee
prior to the initial implementation of the E911 system.  This sub-committee
will establish post implementation quality assurance procedures to ensure that
the E911 system continues to provide quality service to the customer.
Customer/Company training, trouble reporting interfaces for the customer,
telephone company and any involved independent telephone companies needs to be
addressed and implemented prior to E911 cutover.  These functions can be best
addressed by the formation of a sub-committee of the E911 Implementation Team
to set up guidelines for and to secure service commitments of interfacing
organizations.  A SSC/MAC supervisor should chair this subcommittee and include
the following organizations:

1) Switching Control Center
        - E911 translations
        - Trunking
        - End office and Tandem office hardware/software
2) Recent Change Memory Administration Center
        - Daily RC update activity for TN/ESN translations
        - Processes validity errors and rejects
3) Line and Number Administration
        - Verification of TN/ESN translations
4) Special Service Center/Major Account Center
        - Single point of contact for all PSAP and Node to host troubles
        - Logs, tracks & statusing of all trouble reports
        - Trouble referral, follow up, and escalation
        - Customer notification of status and restoration
        - Analyzation of "chronic" troubles
        - Testing, installation and maintenance of E911 circuits
5) Installation and Maintenance (SSIM/I&M)
        - Repair and maintenance of PSAP equipment and Telco owned sets
6) Minicomputer Maintenance Operations Center
        - E911 circuit maintenance (where applicable)
7) Area Maintenance Engineer
        - Technical assistance on voice (CO-PSAP) network related E911 troubles

Maintenance Guidelines
The CCNC will test the Node circuit from the 202T at the Host site to the 202T
at the Node site.  Since Host to Node (CCNC to MMOC) circuits are official
company services, the CCNC will refer all Node circuit troubles to the SSC/MAC.
The SSC/MAC is responsible for the testing and follow up to restoration of
these circuit troubles.

Although Node to PSAP circuit are official services, the MMOC will refer PSAP
circuit troubles to the appropriate SSC/MAC.  The SSC/MAC is responsible for
testing and follow up to restoration of PSAP circuit troubles.

The SSC/MAC will also receive reports from CRSAB/IMC(s) on subscriber 911
troubles when they are not line troubles.  The SSC/MAC is responsible for
testing and restoration of these troubles.

Maintenance responsibilities are as follows:

SCC*            Voice Network (ANI to PSAP)
                *SCC responsible for tandem switch
SSIM/I&M        PSAP Equipment (Modems, CIU's, sets)
Vendor          PSAP Equipment (when CPE)
SSC/MAC         PSAP to Node circuits, and tandem to PSAP voice circuits (EMNT)
MMOC            Node site (Modems, cables, etc)

Note:  All above work groups are required to resolve troubles by interfacing
       with appropriate work groups for resolution.

The Switching Control Center (SCC) is responsible for E911/1AESS translations
in tandem central offices.  These translations route E911 calls, selective
transfer, default routing, speed calling, etc., for each PSAP.  The SCC is also
responsible for troubleshooting on the voice network (call originating to end
office tandem equipment).

For example, ANI failures in the originating offices would be a responsibility
of the SCC.

Recent Change Memory Administration Center (RCMAC) performs the daily tandem
translation updates (recent change) for routing of individual telephone

Recent changes are generated from service order activity (new service, address
changes, etc.) and compiled into a daily file by the E911 Center (ALI/DMS E911

SSIM/I&M is responsible for the installation and repair of PSAP equipment.
PSAP equipment includes ANI Controller, ALI Controller, data sets, cables,
sets, and other peripheral equipment that is not vendor owned.  SSIM/I&M is
responsible for establishing maintenance test kits, complete with spare parts
for PSAP maintenance.  This includes test gear, data sets, and ANI/ALI
Controller parts.

Special Services Center (SSC) or Major Account Center (MAC) serves as the
trouble reporting contact for all (PSAP) troubles reported by customer.  The
SSC/MAC refers troubles to proper organizations for handling and tracks status
of troubles, escalating when necessary.  The SSC/MAC will close out troubles
with customer.  The SSC/MAC will analyze all troubles and tracks "chronic" PSAP

Corporate Communications Network Center (CCNC) will test and refer troubles on
all node to host circuits.  All E911 circuits are classified as official
company property.

The Minicomputer Maintenance Operations Center (MMOC) maintains the E911
(ALI/DMS) computer hardware at the Host site.  This MMOC is also responsible
for monitoring the system and reporting certain PSAP and system problems to the
local MMOC's, SCC's or SSC/MAC's.  The MMOC personnel also operate software
programs that maintain the TN data base under the direction of the E911 Center.
The maintenance of the NODE computer (the interface between the PSAP and the
ALI/DMS computer) is a function of the MMOC at the NODE site.  The MMOC's at
the NODE sites may also be involved in the testing of NODE to Host circuits.
The MMOC will also assist on Host to PSAP and data network related troubles not
resolved through standard trouble clearing procedures.

Installation And Maintenance Center (IMC) is responsible for referral of E911
subscriber troubles that are not subscriber line problems.

E911 Center - Performs the role of System Administration and is responsible for
overall operation of the E911 computer software.  The E911 Center does A-Z
trouble analysis and provides statistical information on the performance of the

This analysis includes processing PSAP inquiries (trouble reports) and referral
of network troubles.  The E911 Center also performs daily processing of tandem
recent change and provides information to the RCMAC for tandem input.  The E911
Center is responsible for daily processing of the ALI/DMS computer data base
and provides error files, etc. to the Customer Services department for
investigation and correction.  The E911 Center participates in all system
implementations and on-going maintenance effort and assists in the development
of procedures, training and education of information to all groups.

Any group receiving a 911 trouble from the SSC/MAC should close out the trouble
with the SSC/MAC or provide a status if the trouble has been referred to
another group.  This will allow the SSC/MAC to provide a status back to the
customer or escalate as appropriate.

Any group receiving a trouble from the Host site (MMOC or CCNC) should close
the trouble back to that group.

The MMOC should notify the appropriate SSC/MAC when the Host, Node, or all Node
circuits are down so that the SSC/MAC can reply to customer reports that may be
called in by the PSAPs.  This will eliminate duplicate reporting of troubles.
On complete outages the MMOC will follow escalation procedures for a Node after
two (2) hours and for a PSAP after four (4) hours.  Additionally the MMOC will
notify the appropriate SSC/MAC when the Host, Node, or all Node circuits are

The PSAP will call the SSC/MAC to report E911 troubles.  The person reporting
the E911 trouble may not have a circuit I.D. and will therefore report the PSAP
name and address.  Many PSAP troubles are not circuit specific.  In those
instances where the caller cannot provide a circuit I.D., the SSC/MAC will be
required to determine the circuit I.D. using the PSAP profile.  Under no
circumstances will the SSC/MAC Center refuse to take the trouble.  The E911
trouble should be handled as quickly as possible, with the SSC/MAC providing as
much assistance as possible while taking the trouble report from the caller.

The SSC/MAC will screen/test the trouble to determine the appropriate handoff
organization based on the following criteria:

    PSAP equipment problem:  SSIM/I&M
    Circuit problem:  SSC/MAC
    Voice network problem:  SCC (report trunk group number)
    Problem affecting multiple PSAPs (No ALI report from all PSAPs):  Contact
                                     the MMOC to check for NODE or Host
                                     computer problems before further testing.

The SSC/MAC will track the status of reported troubles and escalate as
appropriate.  The SSC/MAC will close out customer/company reports with the
initiating contact.  Groups with specific maintenance responsibilities, defined
above, will investigate "chronic" troubles upon request from the SSC/MAC and
the ongoing maintenance subcommittee.

All "out of service" E911 troubles are priority one type reports.  One link
down to a PSAP is considered a priority one trouble and should be handled as if
the PSAP was isolated.

The PSAP will report troubles with the ANI controller, ALI controller or set
equipment to the SSC/MAC.

NO ANI:  Where the PSAP reports NO ANI (digital display screen is blank) ask if
this condition exists on all screens and on all calls.  It is important to
differentiate between blank screens and screens displaying 911-00XX, or all

When the PSAP reports all screens on all calls, ask if there is any voice
contact with callers.  If there is no voice contact the trouble should be
referred to the SCC immediately since 911 calls are not getting through which
may require alternate routing of calls to another PSAP.

When the PSAP reports this condition on all screens but not all calls and has
voice contact with callers, the report should be referred to SSIM/I&M for
dispatch.  The SSC/MAC should verify with the SCC that ANI is pulsing before
dispatching SSIM.

When the PSAP reports this condition on one screen for all calls (others work
fine) the trouble should be referred to SSIM/I&M for dispatch, because the
trouble is isolated to one piece of equipment at the customer premise.

An ANI failure (i.e. all zeroes) indicates that the ANI has not been received
by the PSAP from the tandem office or was lost by the PSAP ANI controller.  The
PSAP may receive "02" alarms which can be caused by the ANI controller logging
more than three all zero failures on the same trunk.  The PSAP has been
instructed to report this condition to the SSC/MAC since it could indicate an
equipment trouble at the PSAP which might be affecting all subscribers calling
into the PSAP.  When all zeroes are being received on all calls or "02" alarms
continue, a tester should analyze the condition to determine the appropriate
action to be taken.  The tester must perform cooperative testing with the SCC
when there appears to be a problem on the Tandem-PSAP trunks before requesting

When an occasional all zero condition is reported, the SSC/MAC should dispatch
SSIM/I&M to routine equipment on a "chronic" troublesweep.

The PSAPs are instructed to report incidental ANI failures to the BOC on a PSAP
inquiry trouble ticket (paper) that is sent to the Customer Services E911 group
and forwarded to E911 center when required.  This usually involves only a
particular telephone number and is not a condition that would require a report
to the SSC/MAC.  Multiple ANI failures which our from the same end office (XX
denotes end office), indicate a hard trouble condition may exist in the end
office or end office tandem trunks.  The PSAP will report this type of
condition to the SSC/MAC and the SSC/MAC should refer the report to the SCC
responsible for the tandem office.  NOTE: XX is the ESCO (Emergency Service
Number) associated with the incoming 911 trunks into the tandem.  It is
important that the C/MAC tell the SCC what is displayed at the PSAP (i.e.
911-0011) which indicates to the SCC which end office is in trouble.

Note:  It is essential that the PSAP fill out inquiry form on every ANI

The PSAP will report a trouble any time an address is not received on an
address display (screen blank) E911 call.  (If a record is not in the 911 data
base or an ANI failure is encountered, the screen will provide a display
noticing such condition).  The SSC/MAC should verify with the PSAP whether the
NO ALI condition is on one screen or all screens.

When the condition is on one screen (other screens receive ALI information) the
SSC/MAC will request SSIM/I&M to dispatch.

If no screens are receiving ALI information, there is usually a circuit trouble
between the PSAP and the Host computer.  The SSC/MAC should test the trouble
and refer for restoral.

Note:  If the SSC/MAC receives calls from multiple PSAP's, all of which are
       receiving NO ALI, there is a problem with the Node or Node to Host
       circuits or the Host computer itself.  Before referring the trouble the
       SSC/MAC should call the MMOC to inquire if the Node or Host is in

Alarm conditions on the ANI controller digital display at the PSAP are to be
reported by the PSAP's.  These alarms can indicate various trouble conditions  o
so the SSC/MAC should ask the PSAP if any portion of the E911 system is not
functioning properly.

The SSC/MAC should verify with the PSAP attendant that the equipment's primary
function is answering E911 calls.  If it is, the SSC/MAC should request a
dispatch SSIM/I&M.  If the equipment is not primarily used for E911, then the
SSC/MAC should advise PSAP to contact their CPE vendor.

Note:  These troubles can be quite confusing when the PSAP has vendor equipment
       mixed in with equipment that the BOC maintains.  The Marketing
       representative should provide the SSC/MAC information concerning any
       unusual or exception items where the PSAP should contact their vendor.
       This information should be included in the PSAP profile sheets.

ANI or ALI controller down:  When the host computer sees the PSAP equipment
down and it does not come back up, the MMOC will report the trouble to the
SSC/MAC; the equipment is down at the PSAP, a dispatch will be required.

PSAP link (circuit) down:  The MMOC will provide the SSC/MAC with the circuit
ID that the Host computer indicates in trouble.  Although each PSAP has two
circuits, when either circuit is down the condition must be treated as an
emergency since failure of the second circuit will cause the PSAP to be

Any problems that the MMOC identifies from the Node location to the Host
computer will be handled directly with the appropriate MMOC(s)/CCNC.

Note:  The customer will call only when a problem is apparent to the PSAP.
       When only one circuit is down to the PSAP, the customer may not be aware
       there is a trouble, even though there is one link down, notification
       should appear on the PSAP screen.  Troubles called into the SSC/MAC from
       the MMOC or other company employee should not be closed out by calling
       the PSAP since it may result in the customer responding that they do not
       have a trouble.  These reports can only be closed out by receiving
       information that the trouble was fixed and by checking with the company
       employee that reported the trouble.  The MMOC personnel will be able to
       verify that the trouble has cleared by reviewing a printout from the

When the CRSAB receives a subscriber complaint (i.e., cannot dial 911) the RSA
should obtain as much information as possible while the customer is on the

For example, what happened when the subscriber dialed 911?  The report is
automatically directed to the IMC for subscriber line testing.  When no line
trouble is found, the IMC will refer the trouble condition to the SSC/MAC.  The
SSC/MAC will contact Customer Services E911 Group and verify that the
subscriber should be able to call 911 and obtain the ESN.  The SSC/MAC will
verify the ESN via 2SCCS.  When both verifications match, the SSC/MAC will
refer the report to the SCC responsible for the 911 tandem office for
investigation and resolution.  The MAC is responsible for tracking the trouble
and informing the IMC when it is resolved.

For more information, please refer to E911 Glossary of Terms.
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