TDM, IP, 2G, 3G, 4G, & 5G Networks

ATM Protocol Analyzer


Asynchronous Transfer Mode (ATM) is a flexible network, which carries voice, video, and data in the same way, i.e. fixed length cells. It has generated a number of revenue opportunities because of its different classes of service support for multimedia traffic, efficient bandwidth management for burst traffic, support for LAN/WAN architecture and high performance via hardware switching.

ATM network basically has two kinds of interfaces i.e. UNI (Interface between ATM User and Public ATM switch) and NNI (Interface between two Public ATM switches). Similar to the OSI Protocol model, ATM has an ATM Layer as Layer 2, ATM Adaptation Layer (AAL) as Layer 3 and other higher layers depending on C-Plane, U-Plane or Layer Management Plane. User information is transferred across U-Plane and signaling messages is transferred across C-Plane. ATM-UNI signaling is used to create and release SVCs along with a particular QoS attached to it depending bandwidth on demand.

GL's ATM Analyzer is used to analyze and decode different ATM protocols like ATM, AAL2 Protocols (CPS-SDU, SSSAR-SDU, and SSCS), AAL5 (CPCS), UNI etc across U plane and C plane of UNI and NNI interface. The analyzer can also decode ATM frames constituting Classical IP over ATM, or CIP based networks, and traditional SS7 Stack (ISUP, SCCP, MAP, CAMEL (CAP) etc) over ATM. The analyzer is also capable of capturing & reassembling frames that were transmitted with Inverse Multiplexing. IMA combines up to 8 T1/ E1 links to form a single high-speed connection with flexible bandwidth options.

GL Communications supports the following types of ATM analyzers:

  • Real-time ATM Analyzer (Pre-requisites: GL's field proven E1 or T1 internal cards or USB Laptop E1 or T1 external units, required licenses and Windows XP (or higher) Operating System)
  • Offline ATM Analyzers(Pre-requisites: Hardware Dongle and Windows XP (or higher) Operating System)

ATM Analyzer Main Features

  • Displays Summary, Detail, Hex-dump, Statistics, and Call Trace Views, the contents of this view can also be copied to clipboard
  • Summary View displays Dev #, Time Slot, Frame #, VPI/VCI, PT (Payload Type), HEC, OSF, AAL Type, Frame Type, CID, LI, CPI, UUI, SSSAR CID and SSCS message type and more in a tabular format
  • Detail view displays decodes of user-selected frames from the Summary View, the contents of this view can also be copied to clipboard
  • Hex dump view displays raw frame data as hexadecimal and ASCII octet dump , the contents of this view can also be copied to clipboard
  • Statistics view displays statistics based on frame count, byte count, frames/sec, bytes/sec etc for the entire capture data
  • Call trace capability based on UNI signaling parameters, VPI/VCI etc
  • CRC verification for AAL5 carrying packet data
  • Support of various UNI Signaling Protocols i.e. UNI 4.0, UNI 3.1 and UNI Q-2931
  • Supports decoding of Classical IP over ATM, Multi-Protocol over ATM, and SS7 signaling over ATM
  • Supports search and filtering capabilities
  • Any protocol field can be added to the summary view, filtering, and search features providing users more flexibility to monitor required protocol fields
  • Ability to configure .ini file to get the proper decoding (customize options such as VPI:VCI values, or detect presence of HEC in ATM header)
  • Capability to export Summary View details to comma separated values (CSV) format for subsequent import into a database or spreadsheet
  • Capability to export detail decode information to an ASCII
  • Option to create multiple aggregate column groups and prioritize the groups as per the requirement to display the summary results efficiently
  • Allows the user to create search/filter criteria automatically from the current screen selection
  • Remote monitoring capability using GL's Network Surveillance System

Additional features supported by Real-time ATM Analyzer are:

  • Captures, decodes, filters, and reassembles AAL-2 and AAL-5 frames in real-time, from within the ATM cells according to user defined VPI/VCI.
  • Recorded raw data can be played back using raw data playback application.
  • The following variations are accommodated in the software: inverted or non-inverted data, byte reversal or non-reversal, with or without Inverse Multiplexing option.
  • Unscrambling of ATM cells based on SDH X^43 + 1 algorithm.
  • Multiple streams of ATM traffic on various T1/E1 channels can be simultaneously decoded with different GUI instances.
  • Streams may be captured on the selected time slots (contiguous or non-contiguous) and on full bandwidth.

Additional features supported by Offline ATM Analyzer:

  • Trace files for analysis can be loaded through simple command-line arguments
  • Multiple trace files can be loaded simultaneously with different GUI instances for offline analysis

Protocols Supported

The list of protocols that are supported by GL's ATM analyzer are as given below:

The supported protocol standards in ATM analyzer are AAL2,5 (UNI 3.1), AAL2,5 (UNI 4.0), AAL2,5 (UNI Q.2931), SS7 ITU, SS7 ANSI, and SS7 ETSI

ATM Protocol Stack

Classical IP Over ATM Protocol Stack

SS7 Over ATM Protocol Stack

Supported Protocols Specification Used
SSCS ITU-T I.366.2
AAL2 Class B (ITU-T I.363.2)
AAL5 Class C & D (ITU-T I.363.5)
UNI Q.2931 & Q.2971
UNI3.1 ATM User-Network Interface Specification Version 3.1
UNI4.0 ATM User-Network Interface Specification Version 4.0
OAM IM for ATM Version 1.1 AF-PHY-0086.001 March, 1999
MAC IEEE 802.3
IP RFC 791
IPv6 RFC 2460, RFC 2402, RFC 2406
ICMPv6 RFC 2463, 2461, 1885, 2894, 3122, 3810, 3775, 3971, 4286, 4066
Payload (Multiprotocol Encapsulation over AAL) RFC2684
Classical IP and ARP over ATM RFC 2225
MTP3b ITU-T Q.2210

Click here to view the protocol glossary page for more information

Summary, Detail, and Hex-dump Views

Summary, Detail, Hex-dump and Statistics Views

The ATM analyzer application is invoked from the main menu of GL's T1/E1 Analyzer for real-time analyzer. The offline ATM analyzer is invoked from the installation directory of the offline ATM Analyzer. The analyzer displays Summary, Detail, Call Trace, Statistics, and Hex dump views in different panes. The Summary pane displays Dev#, Time Slot, Frame#, Time, Length, Error, VPI/VCI, PT and so on. User can select a frame in summary view to analyze and decode each frame in the Detail View. The Hex dump View displays the frame information in HEX and ASCII format. The contents of Detail and Hex Dump view the contents of this view can also be copied to clipboard

Real-time and Offline Analysis

Screen Shot of Timeslot selection

Users can capture and analyze UNI and NNI interfaces in real-time and record all or filtered traffic into a trace file. The recorded trace file can be used for offline analysis or exported to a comma-delimited file, or ASCII file.

ATM raw data capturing requires user to specify timeslots, bit inversion, octet bit reversion, user/network side, ATM mapping, scrambling, and inverse multiplexing options. Captured raw data can then be transmitted using playback file application.

Inverse Multiplexing Over ATM (IMA)

The ATM Analyzer is enhanced to capture & reassemble frames that were transmitted with Inverse Multiplexing option. With Inverse Multiplexing over ATM (IMA) feature, up to 8 T1/E1 links can be configured to form a high-speed connection. ATM cells are transmitted across multiple interfaces in a cyclical fashion, and recombined to form the original stream. By default ATM supports IMA Frame Length equal to 128. User can configure IMA Frame Length ranging from 32, 64, or 256.

Screen Shot of IMA Working Principle

Screen Shot of Captured ATM frames with IMA

Filtering and Search

The user can record all or filtered traffic into a trace file and can create search/filter criteria automatically from the current screen selection. The filter and search options add a powerful dimension to the ATM analyzer that isolates required frames from the captured frames in real-time/remote/offline.

Users can specify custom VPI, VCI, and PT type values to filter frames during real-time capture. The frames can also be filtered after completion of capture according to Dev#, Time Slot, Frame #, Time, Length, Error, VPI/VCI, PT (Payload Type), HEC, OSF, AAL Type, Frame Type, CID, LI, CPI, UUI, and more. Similarly, search capability helps user to search for a particular frame based on specific search criteria.

Screen Shot of Setting the Filtering Criteria

Screen Shot of Setting Real-time Capture Filter

Aggregate Column Group

Aggregate Summary Column Group

The enhanced feature of the protocol analyzer is aggregate column groups. The user can also create multiple aggregate column groups and prioritize the groups as per the requirement to display the summary results in an efficient way.

Display of Aggregate Column Group in Summary View

The updated results are as shown below. Here the root aggregate group~0 summary columns are displayed first and then Group~1 and Group~2 as per the assigned priority.


Screen Shot of Reassembly Parameters

Using reassembly option user can specify VPI /VCI value to reassemble as per the Segmentation and Reassembly rules defined by the specified AAL type. It multiplexes ATM cells as per the user specified VPI/VCI/AAL type into CPS or SAR frames. ATM cells not satisfying the user specification will be reassembled as per the default specification.

Call Detail Record & Statistics View

Screen Shot of Statistics Window

Important call specific parameters like Call ID, Call disposition, Call duration, VPI/VCI, Call type (point-to-point/point-to-multipoint etc) calculated based on UNI signaling messages are displayed in Call Detail Record View. Additionally, users are provided with the option to search a particular call detail record from the captured traces.

Statistics is an important feature available in ATM analyzer and can be obtained for all frames both in real-time as well as offline mode. Various statistics can be obtained in Statistics View to study the performance and trend in the ATM network based on protocol fields and different parameters.

Enhanced Trace Saving Options

Screen Shot of Enhanced Trace Saving Options Window

Users can control the captured trace files by saving the trace using different conventions such as trace files with user-defined prefixes, trace file with date-time prefixes, and slider control to indicate the total number of files, file size, frame count, or time limit. This feature also allows the captured frames to be saved into a trace file based on the filtering criteria set using display filter feature.

Save/Load All Configuration Settings

Screen Shot of Save/Load All Configuration Settings Window

Protocol Configuration window provides a consolidated interface for all the important settings required in the analyzer. This includes various options such as protocol selection, startup options, stream/interface selection, filter/search criteria and so on. Any protocol field can be added to the summary view, filtering, and search features from this GUI providing the users more flexibility to monitor required protocol fields. All the configuration settings done can be saved to a file and then loaded from a configuration file. Users may also just revert to the default settings using the default option.

ATM Emulation Tools

ATM IMA Emulation using Client-Server

GL's IMA (Inverse Multiplexing over ATM) Emulator is available as optional client-server based application with GL's T1/E1 Analysis hardware. The IMA Emulator application can simulate the inverse multiplexing of an ATM cell stream over multiple physical links ( up to 16 T1/E1 ports) and retrieve the original stream at the far-end from these physical links. For more details, click here.

Bridge and Monitor Connections


Please Note1: The XX in the Item No. refers to the hardware platform, listed at the bottom of the Buyer's Guide, which the software will be running on. Therefore, XX can either be ETA or EEA (Octal/Quad Boards), PTA or PEA (tProbe Units), UTA or UEA (USB Units), HUT or HUE (Universal Cards), and HDT or HDE (HD cards) depending upon the hardware.

Item No. Item Description
XX160 T1 or E1 ATM Analyzer
OLV160 Offline T1 or E1 ATM Analyzer
  Related Software
XX020 Record/Playback File Application
XX051 Synchronous Trunk Record Playback
XX120 SS7 Analyzer
XX654 ATM IMA Emulator
XX135 Multi Link PPP Analyzer
XX135 Multi Link PPP Emulator
XX130 Multi Link Frame Relay Analyzer
XX655 Multi Link Frame Relay Emulator
  Related Hardware
PTE001 tProbe™ Dual T1 E1 Laptop Analyzer with Basic Analyzer Software
HDT001/HDE001 Legacy HD T1 or E1 (PCI) Cards with Basic Analyzer Software
HTE001 Universal T1/E1 Card with Basic Analyzer Software
UTE001 Portable USB based Dual T1 or E1 Laptop Analyzer with Basic Analyzer Software
TE3001 USB based T3 E3 Analyzer Unit


Rack Enclosure for T3/E3 System – up to 6 T3/E3s

LTS105 LightSpeed1000 Analyzer Unit for OC-3/STM-1, OC-12/STM-4

* Specifications and features subject to change without notice.

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