Like an air traffic controller monitoring and directing the flow of aircraft around a busy airport, a packet analyzer monitors and directs the flow of data through portals in the Internet. A packet analyzer may also be called a sniffer, a network analyzer, a protocol analyzer or a wireless sniffer, among other things. It is designed to grab packets of data soaring through the network and decode and analyze the data. The packet analyzer will then display the results of this analysis to a network administrator for further action. Or, the packet analyzer may be programmed to automatically actuate repairs to network traffic interruptions.
When the air traffic controller encounters a hold up, either intentional or otherwise, in the smooth flow of air traffic, he or she will assess the problem and decide whether a command, a warning or simply a rerouting of the traffic will fix the problem. A packet analyzer does essentially the same thing for Internet packet flow.
Packets, also known as cells, among other terms, are segments of data or bits from a particular transmission, be it an e-mail message or a streaming video. These bits are broken into a certain size, called bytes, and then sent, via Ethernet or WiFi, over the best route to reach their intended recipient. The routes may be different for each packet of a particular message, depending on the most expeditious and supportive path. As an air traffic controller regulates traffic in an air corridor, a packet analyzer regulates data flow in various network bandwidths.
Each packet usually contains three parts: 1) a header, which are the instructions referring to the data within the packet; 2) the payload or actual data in the packet; 3) the trailer or code telling the receiving device that it is nearing the end of the packet.
Packet analyzers may be either hardware, such as a network card, or software such as coded instructions entered on the net via network devices. The interception, decoding and analysis of data by the packet analyzer results in troubleshooting various routes and receptors, computers or nodes on the network to repair glitches, block inappropriate content and/or gather statistical information regarding the suitability and practicality of particular network support systems.
As a rule, the data contained in packets, as well as the routing of packet transmission, is regulated by Internet Protocol (IP) which is, in turn, directed by Requests for Comments (RFC) regulations. This regulating agency, composed of members of the Internet Engineering Task Force (IETF) is one of several criteria that a packet analyzer is designed to adhere to in its analysis and reporting processes
