Protocol analyzer is a device (either hardware or software) used to verify that a protocol on a digital network is operating correctly, or to extract
data about the protocol, possibly including statistics or data.
- A protocol analyzer for a token ring network could detect that the token
has been lost or the presence of too many tokens (verifying the protocol).
- A protocol analyzer could detect that messages are being sent to a NIC, if the NIC did
not report receiving the messages then this would localize the failure to the NIC.
- A protocol analyzer could detect excessive messages being sent by a port, detecting an error in the implementation.
- A protocol analyzer could collect statistics on the amount of traffic (number of messages) from a process detecting the need
for more bandwidth or a better method.
- A protocol analyzer could be used to extract messages and reassemble into a compete form the traffic from a process, allowing
it to be reverse engineered.