How To Debug and Troubleshoot VOIP

Debugging and troubleshooting VOIP problems.

(SIP, MGCP, H.323, Skinny etc.)

One of the primary techniques is to view what is actually getting sent and received by VOIP devices. There are several ways to do this:

Monitor Ethernet Traffic
Debugging displays from a VOIP program

It helps to understand whats supposed to be happening. Studying the relevant s and other protocol documents and tutorials is helpful.

Ethernet Monitoring Tools

(Ex ) (Open Source and available for Linux, Windows, Apple, BSD, etc.)
- Support for decoding many VOIP protocols is included (including IAX)
- analysis and call flow diagram for (SIP, MGCP, H323, etc.)
- and graph analysis (jitter, delay, packet lost, etc.)
- RTP playback (Wireshark only)
- Test Solutions for VoIP networks and devices
(standard utility in most Linux distributions)
- tcpdump for Windows
(Available for Linux, Windows, Apple, BSD, etc.)
- Dumps only the ASCII portion of packets, excellent for ASCII based protocols
: User-friendly packet sniffer for Windows, supports SIP
List of Monitoring and sniffing software
which provides real time packet-per-second and data transfer rates
- - a free VMWare appliance
- - sophisticated monitoring and flow analysis tool with visualisation, multiple data sources, ...
CommView - network analyzer for Windows
- Real-time VoIP call monitoring
- SIP and H.323 analysis and decoding, call playback
- Jitter, QoS, Bandwidth charts
- WinEyeQ
  - 100% software-based
  - monitors/analyzes/records/replays and traffic, audio/video media and .
- TraceBuster (free version available)
  - records/replays and traffic, audio/video media and .
Displays SIP ladder diagram from WireShark/pcap captures
- Displays STUN/TURN interactions
- Allow users to filter on particular call flows

Built-in Debug Tools

The x-lite and x-pro SIP soft phones have a buit-in display and decoding of received and sent SIP packets (Hit F9 to activate)
Use the sip debug command
Outputs useful diagnostics to the console as it uses the oSIP library
A command line SIP user agent from , available for various platforms, and very useful to debug SIP functionalities (call, presence, instant messaging, etc.) as well as media quality via RTCP statistics.

Traffic generators

- Simulate and Stress Test all types of VoIP networks
- Test Solutions for VoIP networks and devices
LANForge FIRE VOIP/RTP/PESQ call generator
Signaling and Media load and feature testing
- PacketGen - generates SIP calls with or without RTP traffic
- PacketScan - monitor, collect, and analyze QoS statistics on VOIP traffic
Prognosis will simulate, record and analyze VOIP traffic in real time.
creates network traffic and measures performance
- Can be used to test a network to see how it might perform with increased VOIP traffic
VOIP traffic generators and Network assessment tools
simulates VoIP traffic over your Internet connection, measures key diagnostics including Jitter and Packet Loss, and provides an analysis of the voice quality
4"x4" in-line micro-appliances used in a distributed multi-site enterprise or SME to generate live VoIP traffic and measure loss, jitter, MOS, route performance, route flaps, etc. Also measures ongoing data traffic in network.
SIP Performance Test Tool - Performance tester for SIP
Open source call generator from to measure SIP call/transaction performance.
100% software-based VoIP and video verification tools.
- WinSIP - SIP signaling and Audio/Video media generator
- Win323 - H.323 signaling and Audio/Video media generator
Valid8.com is a leading provider of SIP, H.323, Megaco, SIGTRAN traffic generation solutions.

Monitoring and Test Tools

: VoIP Speech Quality Analysis System
DNA MX and TNA software
real-time VoIP performance management and service assurance solutions
Monitoring and high level flow analysis and visualization
ClearSite Analyzer
VoIP Management from pre deployment to post deployment and network visualization in Visio
monitoring and analysis
OptiView VoIP, ProtocolExpert Plus and Link Analyzer
Call Monitoring, Analysis and Reporting
monitoring and testing
monitoring of and network performance
monitoring of and network performance
micro-appliances and asterisk agent for QoS monitoring of SIP and Cisco SCCP VoIP calls
SwitchMonitor VoIP
Clarinet Protocol Test System
- Simulation and analysis of , SIP-T & . measurement, recording, replay etc.
monitoring of
monitoring of
Analog QOS products - can be used with an
VOIP test equipment and systems
- Test Solutions for VoIP networks and devices
VOIP and Telecom test equipment
and network analyzers for wired and wireless (802.11 a/b/g/n) networks
- Real-time VoIP call monitoring
- SIP and H.323 analysis and decoding, call playback
- Jitter, QoS, Bandwidth charts
monitoring of
- Their technology appears in numerous other products
- WinEyeQ
  - 100% software-based
  - monitors/analyzes/records/replays and traffic, audio/video media and .
- TraceBuster
  - records/replays and traffic, audio/video media and .
RTP/SIP/IAX2 visual analysis, one-click playback, whitepapers
Valid8.com is the leading provider of SIP, H.323, Megaco, SIGTRAN conformance test solutions.
NetAlly RealTime and VoIP Assessment
Efficient VoIP SLA monitoring and troubleshooting tools.
web-based, 24 X 7 real-time QoS monitoring tool for VoIP networks.
EtherPeek VX - monitor , packet loss, voice quality, etc.
See Also:
- of 7 VOIP Analysis Tools

Asterisk Tools

A simple script for viewing Asterisk config files with comments and empty lines removed.

Network Impairment Simulators

hardware appliance to emulate WAN bandwidth, delay, and loss up to 155 Mbps.
LANForge ICE Network Emulator
simulates many types of network impairments
allows a single Linux PC set up as a router to emulate a wide variety of network conditions
Shunra Virtual Enterprise (Shunra VE) network simulator creates a model of any production environment, including the network, remote locations, and the number and distribution of local and remote end-users. With Shunra VE, users can test the functionality, performance, scalability and robustness of the VoIP infrastructure under current and future production conditions â