13 Important Protocol Analyzer Glossary Terms

Protocol Analyzer

Also known as a network analyzer or a sniffer, a protocol analyzer is a hardware or software-based tool that logs information about traffic in a network. Analyzers can be used to detect potential problems and weaknesses in a network and can analyze information from packets to provide useful data, which can then be used to optimize efficiency and improve network infrastructure.

Data Rate

The rate at which a network transfers information, usually in packets. Protocol analyzers will typically log data rates automatically, as this can be an important number to use when analyzing a network.

Event Sequencing

A feature that allows a protocol analyzer to run a series of actions to capture, filter and analyze information.


Hardware or software that creates a variety of different errors or purposely tries to overload a system for the purposes of testing. Exercisers are often built in to protocol analyzers and many have simple GUIs.

Lane Reversal

A technique for simplifying communications between two components or a component and a connector. Lane reversal consists of a configuration option that stripes packet data between two lanes, effectively re-routing the lanes of two devices. Only one device needs to support lane reversal in order to use the feature.

Lane-to-Lane Skew

Although multiple lanes may be simultaneously transferring data packets, those packets will not always arrive at the same time, which results in a problem known as lane-to-lane skew. Many protocol analyzers have features designed to minimize lane-to-lane skew and to allow for improved performance.

Lanes, Number of

Lanes carry packets of data to and from components. Components are restricted in data transfer capabilities by their number of lanes.


Data transferred through a network. Packets consist of bundled information using various protocols along with information that allows them to arrive at the appropriate destination.

Protocol Decodes

Decodes allow packet data to be displayed in a human-readable format. Protocol decodes often need to be regularly updated and most protocol analyzers have a large number of built-in protocol decodes to improve user functionality.

Protocol Layer

Different nodes of a packet data network communicate with a layered protocol, as layers help to keep the design of the packet to a small size. Protocol layers are independent and are simple to change as needed, where older designs were much more complex and difficult to work with.

Time Stamping

Protocol analyzers capture data in packets, which are each time-stamped. The process of time stamping can be helpful when time-sensitivity could affect collected data, for instance when tracking network speed during different times of the day. Protocol analyzers typically use the operating system's kernel to set time stamps.

Time-Stamp Range

Can refer to the difference in time stamps between two or more captured packets or between two different systems. Time-stamp range can also refer to the accuracy of a protocol analyzer's time-stamping capabilities.

Traffic Filters

When a protocol analyzer is being operated remotely, packet traffic can be excessive and many packets will be of negligible importance. Traffic filtering helps the analyzer avoid useless packets while still collecting packets that appropriately match the connection.