#How to use wireshark to test voip software

One of the most fundamentally useful and diversely applicable tools is a packet sniffer.Ī packet sniffer is a piece of software running on a computer that can capture and analyze packets traversing the network. Data networking professionals have a number of tools at their disposal to diagnose and resolve problems on the network, and these can be useful for voice engineers, as well. Network troubleshooting tools and techniquesįor this reason, it is important to approach VoIP troubleshooting from the point of view of data networks. Troubleshooting experience and techniques used in conventional telephony are of limited value when applied to VoIP. This fundamental difference profoundly affects how troubleshooting is approached in each case. Packets may take various paths to get to their destination, where they are reassembled into the original voice conversation. This means that the voice of a caller being transmitted over the network infrastructure is broken down into small pieces or packets that are sent individually. VoIP, on the other hand, which takes advantage of IP networks, is packet switched. This is true even of ISDN circuits, which operate in a similar manner even though they are digital. Traditional voice is primarily circuit switched, which means that connections are made from end to end whenever a call is initiated, and are torn down once the call is complete. The troubleshooting procedures for any kind of application that is running on an IP network are quite different from those involved in traditional telephony. The nature of conventional voice compared with VoIP In this article we look at a nifty tool called a packet sniffer that can be used for troubleshooting many types of VoIP problems and should be in the toolbox of any telephone installer. So, if you’re an expert in ISDN, SS7 or other conventional telephony technologies, it’s essential to also be familiar with data networking fundamentals to remain competitive and relevant in the telecom industry. If you go in on the voice side of things, you will inevitably become involved with the data side, as well.” As Voice over IP (VoIP) technologies are overtaking more traditional telephony systems such as ISDN and analog, the voice engineer is required to know data networking fundamentals in order to implement, maintain and troubleshoot modern voice systems.īack in 1999, when VoIP was still in its infancy, Industry Expert Bruce Robertson told students in the Sheridan College Telecommunications Management post graduate program, “If you go into the telecom industry on the data side, you will probably stay on the data side for all of your career. If you’re on the voice side of the telecommunications industry, it is inevitable that you will be dealing with data networking. In this diagram, it is much more convenient to analyze VoIP-traffic for diagnostics (debugging), but it will require knowledge of the principles of the SIP data transmission protocol (Session Initiation Protocol). The Graph Analysis window will appear with a graphical diagram of the VoIP call data exchange. Select a VoIP call and then click the Graph button (or Flow, depending on the version of the program). Packets: The number of packets participating in the call.ģ.To: For SIP calls, the INVITE request is displayed in the 'To' field.

From: For SIP calls, the INVITE request is displayed in the 'From' field.

Initial Speaker: The IP address of the packet source that initiated the call.

The list of VoIP calls shows the following information for each call: The VoIP Calls window opens with a list of VoIP calls. Go to the Statistics menu (or Telephony, depending on the version of the program) > VoIP Calls. sip or rtp to display only a certain type of traffic.Ģ. To filter packets, you can enter a value in the Filter field. Select a SIP or RTP packet from the list (in our example, analyze the RTP traffic). Suppose that during the execution of a VoIP call using Wireshark, network packets were captured and this dump should be analyzed.ġ. Wireshark allows you to analyze the SIP protocol and its RTP traffic.

The Wireshark program implements a convenient mechanism for diagnosing (analyzing) VoIP calls, in particular, you can get a graphical diagram of calls and see how data was exchanged. Is there a more convenient and efficient way to debug VoIP using the Wireshark traffic analyzer? When debugging (diagnosing) an IP telephony service, it is very difficult to analyze VoIP traffic.

How to use wireshark to test voip