Protocol Analyzer

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

PPP Protocol Analyzer

(w/ PPP, MLPPP, & MC-MLPPP Decode Support)


The MLPPP Analyzer can be used to capture and decode a host of PPP protocols exchanged between pairs of nodes over T1/E1 links. It provides useful analysis of the PPP, MLPPP, and MC-MLPPP protocols which includes distribution of protocols, protocol fields, frame lengths and frame status.

A user can obtain detail analysis of the protocol and can perform various statistics measurements. MLPPP analyzer also supports Packet Data Analysis module (requires additional license) to perform detail analysis of MLPPP packets over IP and segregates them into SIP / H323 / Megaco / MGCP / T.38 Fax calls.

GL Communications supports the following types of MLPPP analyzers:

  • Real-time MLPPP Analyzer with Packet Data Analysis (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/Remote MLPPP Analyzer (Pre-requisites: Hardware Dongle and Windows XP (or higher) Operating System)

The Packet Data Analysis  is an outstanding tool for live monitoring of signaling and traffic over IP.Packet Data Analysis (PDA) is distributed with GL’s Packet Analyzers, allowing users to monitor live IP networks including capture, analysis, and reporting of every call in detail. Supported protocols include SIP, MEGACO, MGCP, H.323, SCCP, RANAP (UMTS IuCS), and GSM A. It can capture IP packets over different transmission lines, including IP, T1, E1, T3, E3, and OC-3 STM-1 / OC-12 STM-4. PDA then processes the captured packets, identifies, and segregates calls based on signaling and traffic parameters. Refer to Packet Data Analysis in MLPPP webpage for more details.

In addition, GL's T1E1 Analyzer includes client-server based MC-MLPPP Emulator that can further help in analysis & emulation of MC-MLPPP, MLPPP, & PPP.

Main Features

  • Supports a host of protocols PPP, MLPPP, Multi-class MLPPP, IPCP, BCP, PPP MUX CP, IEC, CRTP, BPDU, PAP, CHAP, SNMP, STUN, DNS, and DHCP.
  • Ability to test and perform numerous measurements across WAN- LAN or LAN-LAN connection.
  • Ability to test and analyze HDLC based PPP protocol, PPP SIGTRAN, and PPP over IP protocols in synchronous environment.
  • Search and filtering capabilities for both real-time as well as offline analysis.
  • Displays Summary, Detail, Hex-dump, Statistics, and Call Trace Views, the contents of this view can also be copied to clipboard.
  • Summary View provides the information about few important fields (Dev #, Time Slot, Layer 3 Protocol, LCP message type and higher protocol specific information like Destination and Source IP address, Destination and Source TCP as well as UDP port details, and so on).
  • Statistics View displays statistics based on frame count, byte count, frames/sec, bytes/sec etc for the entire capture data.
  • Hex dump view displays raw frame data as hexadecimal and ASCII octet dump, the contents of this view can also be copied to clipboard.
  • Detail View displays decodes of user-selected frames from the Summary View.
  • Provides reassembly error details regardless of which fragment is missing/erred. Includes counters for fcs errors, reassembled erred packets, and number of duplicate packets
  • Also supports Packet Data Analysis module for real-time IP call analysis including SIP, RTP, MEGACO, H.323, & MGCP & T.38 Fax calls.
  • Any protocol field can be added to the summary view, filtering, and search features providing users more flexibility to monitor required protocol fields.
  • Supports decoding of frames with two MLPPP layers.
  • Detail information of all the captured Frames or only the filtered frames can be exported to ASCII file for the further off-line analysis and printed.
  • Capability to export Summary View details to comma separated values (CSV) format for subsequent import into a database or spreadsheet.
  • Capability to export detail decodes information to an ASCII file.
  • Multiple bundle of MLPPP traffic on various T1/E1 channels can be simultaneously decoded with-in same or different GUI instances.
  • Ability to configure .INI file to customize sequence fragment format.
  • Remote monitoring capability using GL's Network Surveillance System.

Additional features supported by MLPPP Real-time Analyzer:

  • A single instance of the analyzer supports reassembly and decoding of multiple MLPPP bundles simultaneously. Each MLPPP bundle is created by selecting groups of timeslots on various cards. Each group of timeslot selection can have different data rates.
  • Supports CRC selection with CRC-16, CRC-32, and CRC-NONE options for each link in MLPPP bundle.
  • Various data transmission rates starting from fractional DS0 to DS1 (subchannels) are supported. Frames can be transmitted/captured in either, n x 64 kbps, or n x 56 kbps data channels.
  • Supports selection of TS0 in E1 analyzer for the analysis of unframed data.
  • The other variations accommodated in the software are inverted or non-inverted data, byte reversal or non-reversal, and MLPPP options such as fragment format (long or short), & maximum differential delay.
  • Ability to capture and decode both PPP routed protocols, PPP bridged protocols, MLPPP and MC-MLPPP streams of data.
  • User can decode frames from the recorded trace files and can be played back using HDLC playback application.

Additional features supported by Offline MLPPP 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.


  • RFC 1661 Point-to-Point Protocol (PPP) and Link Control Protocol (LCP)
  • RFC 1662 Physical Layer and HDLC Layer
  • RFC1990 Multi-link PPP bundles
  • RFC2686 Multi-class extensions to PPP
  • RFC 1332 The PPP Internet Protocol Control Protocol
  • RFC 1877 PPP Internet Protocol Control Protocol Extensions for Name Server Addresses
  • RFC 3518 PPP Bridging Control Protocol
  • RFC 1144 Van Jacobson Compression
  • RFC 3544 IPHC Compression
  • RFC 2507 only IP Compression
  • RFC 2508 Compressed RTP
  • RFC 3153 PPP Network Control Protocol for PPP Multiplexing (PPPMuxCP)

Protocols Supported

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

The supported protocol standards in PPP analyzer are PPP, PPP SIGTRANs.

Supported Protocols Specification Used
PPP RFC 1331,1220,1333,1548,1661,1570
IP RFC 791
SNMP(V1, V2) RFC 1157,1155,1902,3416,2863,2578,3418,2011,2012 etc
DNS RFC 1035
DHCP RFC 1533, 2131
RIP RFC 2453
VJ Compressed TCP/IP RFC 1144
VJ Uncompressed TCP/IP RFC 1144
Multiplexed PPP RFC 3153
Cisco HDLC
CHAP (Challenge Handshake Authentication Protocol) RFC1334
IPHC (IP Header Compression) RFC 2507, RFC 3544
LCP (Link Control Protocol) RFC1570, RFC1661
LQR (Link Quality Report) RFC1333
MultiPPP (PPP Multilink Protocol) RFC1717, RFC1990
Multi-class extensions to PPP (MC MLPPP) RFC 2686
PAP (Password Authentication Protocol) RFC1334
PPP (Point-to-Point Protocol) over HDLC RFC1662
PPP-BPDU (PPP Bridge Protocol Data Unit) RFC1638
BCP (Bridging Control Protocol) RFC 3518
Internet Protocol Control Protocol Extensions for Name Server Addresses RFC 1877
IPCP (IP Control Protocol) RFC1332
IEC IEC60870-5-101, IEC60870-5-103, IEC60870-5-104
SIP3261 RFC 3261
RTP RFC 2833
H.263 ITU-T H.263
H.245 ITU-T H.245
H.450 ITU-T H.450.1 to H.450.12
ISDN H.225 H.225 Q.931 Layer
T.38 ITU-T T.38
MPEG2 RFC 2250
M2UA RFC 3331
M2PA RFC 4165
M3UA RFC 3332
MTP3 ITU-Y Q.701-Q.705 / ITU-T Q.782
ISUP ITU - Q.761, Q.762, Q.763 and Q.764
SCCP ITU-T Q.711-Q.714
IUA (ISDN UA) RFC 4233 / RFC 5133
TUP T-REC-Q.723-11/1988
Test & Network Management Messages (ITU) ITU-T Q.703, Q.704

Click here to view the protocol glossary page for more information

Real-time and Offline Analysis

The application supports reassembly and decoding of multiple MLPPP bundles simultaneously. Each MLPPP bundle will reassemble packets from PPP links. Multiple cards can be selected for a single instance of analyzer to capture the frames simultaneously. Users can capture and analyze PPP frames carried on n*DS0 channel 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, or printed.

The real-time capturing requires users to specify timeslots, bit inversion, octet bit reversion, hyper channel selection, CRC, and mlppp options such as Fragment format & Maximum differential delay. The maximum delay value (that is the maximum time the analyzer waits for the reassembly of the MLPPP fragment) allows minimizing the sequence loss. The captured raw data can then be transmitted using HDLC Playback-file application.

Screen Shot of Timeslot selection

Summary, Detail and Hex dump Views

The MLPPP analyzer application is invoked from the main menu of GL's T1/E1 Analyzer for real-time analyzer. The offline MLPPP analyzer is invoked from the installation directory of the offline MLPPP Analyzer. The analyzer displays Summary, Detail, Statistics, and Hex dump views in different panes. The Summary View displays Dev#, Time Slot, Sub Channel, Frame #, Time relative, Len, Error, Layer 3 protocol, LCP code, Seq No, Class, IPCP code, BCP code, Class, PPP Message type, Source/Destination IP address, TCP Source/Destination Port, UDP Source/Destination Port, and so on. The 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.

Screen Shot of Summary, Detail and Hexdump Views

Filtering and Search

Users can record all or filtered traffic into a trace file. Filter and search capabilities adds a powerful dimension to the MLPPP Analyzer. These features isolate required frames from the captured frames in real-time, as well as offline. In real-time capturing, filter based on length of frames can be set. The frames can also be filtered after completion of capture based on Frame Number, Time, Length, Error, Layer3 Protocol, LCP Code, IPCP code, Sequence number, Mlppp class, TCP and UDP source and destination port ,PPP Message type, and so on. Similarly, Search capability helps user to search for a particular frame based on specific search criteria.

Screen Shot of Setting the Offline Filtering Criteria - PPP Protocol Stack

Statistics View

Statistics is an important feature available in MLPPP analyzer and can be obtained for all frames both in real-time as well as offline mode. Various statistics can be obtained to study the performance and trend in the PPP network based on protocol fields and different parameters e.g. User Type (Key/Total/Field), Statistic type (Frame count, Byte count, Frames/Sec) and patterns like Range List, Wild card.

Screen Shot of Statistics View

Enhanced Trace Saving Options

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.

Screen Shot of Enhanced Trace Saving Options Window

MLPPP Analyzer with Packet Data Analysis

MLPPP Packet Data Analyzer (PDA) is a real-time IP and VoIP analyzer that non-intrusively analyzes and captures live IP traffic, and segregates them into SIP / H323 / Megaco / MGCP / T.38 Fax calls. It also collects statistics, CDRs, detailed protocol traces, ladder diagrams, and a host of other useful information about VoIP calls.

Its real-time nature makes it an outstanding tool for live monitoring of VoIP traffic as well as long-term traffic statistics gathering. It can also monitor, report, analyze, and capture calls for infinite time, limited only by the finite space of your hard disk or network hard drive.

For more information, refer to Packet Data Analysis in MLPPP webpage for more details.

Screen Shot of MLPPP PDA


Please Note: 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
XX135 T1 or E1 MLPPP Analyzer
OLV135 Offline T1 or E1 MLPPP Analyzer
XX136 PPP and MLPPP Packet Analysis - Real-time Packet Voice, Video, and Fax Analysis
  Packet over TDM CDR Analysis System
  (The system requires any of the below mentioned T1 or E1 platforms with Basic Software)
  Refer to CDR Buyer's Guide
  Related Software
XX020 Record and Playback of Files
XX051 Synchronous Trunk Record Playback
XX634 Multi-Channel HDLC Emulation and Analysis & File based High Throughput HDLC Record/Playback
XX635 PPP Emulation and Analysis
XX636 MC-MLPPP Emulation and Analysis
XX640 File based HDLC Record/Playback
  Related Hardware
PTE001 tProbe™ Dual T1 E1 Laptop Analyzer with Basic Analyzer Software
PTE025 Datacom Analyzer Board for RS-232, RS-449, RS-422, RS-423, EIA-530, V.35 Interfaces
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

* Specifications and features subject to change without notice.

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