Network Instruments Observer 11

We found the VoIP analysis functions superior to those offered by Network General's Sniffer software (see issue 142 of PC Pro for the full review). The amount of information provided was about the same but Observer presented it more tidily making it more accessible. From a single window it provides a full summary of VoIP traffic and shows jitter and lost packets. Each VoIP call is listed and you can see at a glance what the phone numbers for the source and destination are along with the call duration. Observer also has the ability to rate the quality of VoIP calls as it calculates a MOS (mean opinion score). This is derived from dropped packets and jitter and aims to predict how the call quality would be rated by an actual user.

For its sheer number of features Observer is in a league of its own. There haven't been too many updates to the base product on this release but the Expert version delivers excellent VoIP analysis and stream reconstruction features. Furthermore, when you consider that the equivalent Sniffer product from Network General with VoIP analysis will set you back around twice as much it's clear Observer is extremely good value as well.

Author: Dave Mitchell