I have a small network of Mac systems, and would like to add some internal monitoring of our internet usage, which has recently begun to climb. I would like to configure one of the machines as an internet gateway, and install some monitoring software that could provide graph indications of network usage by machine.
The machine would then double as a workstation and as the internet gateway. I can manually configure the machines on the network to use it as a gateway, and would prefer to avoid an explicit http proxy (although it is an option if necessary).
What software would serverfault users recommend to provide simple, easily configurable and maintainable network monitoring on Mac OS 10.5.7 (non-server)? The simplest requirement is monitor usage by IP Address, but additional tracking (e.g. destination, protocol, etc) would be useful.