Maximize the potential of PSTN network

The Maestro system, replacing the well known system Mirabel (precursor of maintenance systems PSTN), was designed to perform physical tests telephone lines and provide a simple diagnostic and localization of defects as well as qualifying these lines to support xDSL services.

These tests can be launched by

field technicians in charge of maintenance,

customer support in 7/24,

analysts in charge of preventive maintenance (by batch of test to analyse status of cables by example),

analysts in charge of marketing to promote/propose services only where they can be available (eligibility).

The system can easily

be integrated inside IS to be able to:

  • get information regarding telephone lines in databases,
  • offer NBI to allow tests submission or retreive historic measurements,

use different exchanges (E10, EWSD...), DSLAM or MSAN.

The know-how of Vierling R&D teams during these last 25 years, has created

an equipment to perform quickly, thousands of measurements per copper pair

a complex software and algorithms to:

  • generate a reliable diagnostic based on these measurements,
  • automatically detect elements on line (splitters, NID, phone sets, xDSL modems…).

Measurements and diagnostics provided by MTDU

xDSL eligibility measurements


Line Attenuation at 150kHz, 300kHz and 1MHz

Upstream and downstream ADSL and ADSL2+ rates

Line elements detected

Phone set, Fax, Modem (on/off)

RC socket, C socket or other NID

CO xDSL splitter

xDSL modem and/or splitter in client premise

Current limiter

Maintenance measurements

DC voltages: A/B, A/G and B/G

AC voltages: A/B, A/G, B/G, A/Bat. and B/Bat.

Resistances: A/B, A/G and B/G

Capacitances: A/B, A/G, B/G and EFF

DC currents: A/B, A/G and B/G

AC currents: A/B, A/G and B/G

Noise in vocal and xDSL bands

Fault location


Line Good in Test

Open 1 wire (A or B wire)

Open 2 wires

Unbalanced line

Insulation fault Ground (A or B wire)

Insulation fault between wires

Insulation fault between a wire and battery (A or B)

Multiple insulation faults

DC voltage presence (A or B wire)

DC voltage presence (between wires)

AC voltage presence (A or B wire)

AC voltage presence (between wires)

HR joint (A or B wire)

LF noise presence (voice band)

Balance fault in xDSL band

HF noise presence (xDSL band)

Which services can be tested

  • Upon interrogation by server to GM-EN2
  • Resynchronization request or not
    • Checking the status of transmission
  • Condition and performance of the IP layer
    • Reading the IP configuration
    • pingtraceroute (packet loss, delay, routing)
    • DNS test
  • Condition and performance of services
    • FTP (access, rates…)
    • HTTP (access, rates…)
    • VoIP (access to the platform, call…)
    • IPTV (accessibility, zap time…)
  • Flexibility to test new services

Recently, dbeeSet Technology decides to offer all its know-how in this domain inside a portable solution which contains the same hardware and clever algorithms as the Maestro system.

This equipment helps field technicians to do campaign measurements:

create eligibility database and help marketing to provide right services to right clients

validate MSAN deployment before commissioning

test unused pairs and provide astatus for the whole cable

Maestro system architecture
and its integration inside IS

Principles – Sequence of a test

A test is launched by providing the sole phone number of the line (by example).

The server interrogates databases to identify on witch commutator (switch, DSLAM, matrix…) this line is related to.

The server pilotes the MTA (Metallic Test Access) function of the commutator to be able to establish a metallic link between the line and a test port of a MTDU.

The server identifies on which MTDU, the line has been returned.

MTDU performs all necessary measurements to establish a comprehensive diagnostic.

The server pilotes the MTA function of the commutator to release the line.

The server stores and displays value results and diagnostic to user.

Tests Web Application

After authentification and regarding the profile of the user.

On-demand tests

Run a line test and display results


MIB DSLAM Information

Internal information from commutator

Combined test (line + MIB)

Test xDSL plot and services

Historical results

Bulk tests

Lines selection according various criteria

Automatic (newly created lines, faulty lines…)


Export results to backoffice treatments

ADMIN Station – Configuration management