How can I monitor network traffic in an all Mac home network?

Question

I have an all Mac network consisting of an Airport Extreme, 1 MacPro, 1 Mac Mini, 2 MackBook Pros, 2 iPads, and 2 iPhones. The Mac Pro is connected directly to the Airport Extreme via Cat5 and the rest is all running via Wireless.

Lately I've been getting prompted by Google to enter Capchas frequently. The message states that I might have software running on my network I'm not aware of. My wireless router is password protected using WPA2 Personal and I frequently change my password so I don't think someone is using the network from outside (but I've no way to confirm this).

I'm looking for a relatively cheap (preferably open source) solution that would enable me to monitor and profile the network usage by machine and port.

Can someone recommend a solution?

Answer 1

If you want all the geeky details, you probably want MRTG.

It uses SNMP to monitor your router(s) and draws nice graphs. It's written in Perl, so it should run on Mac OS X as well as generic UNIX/Linux.

Answer 2

Eavesdrop is a good Mac-native network sniffer.

Answer 3

I've been having the same problem with Google plus experiencing sporadic streaming hiccups on my Apple TV. After looking around and following a few links here, I ended up referencing traffic via Airport Utility » Base Station » Logs and Statistics. The same dialogs can also be accessed via the Advanced button along the top of the floating dialog box. Here you will find info on devices that have been connecting to your WiFi/Airport and last time each one connected.

That said, I didn't see any external access to my network so I'm still not sure what is causing my problems. I do plug into a network within my condo that connects thru Dish Network. The Google problem may be a result of traffic being generated by other tenants, but that still doesn't explain sluggish streaming within my LAN.

Answer 4

You can try NetUse Traffic Monitor. It uses SNMP to get network usage data off your router and draws realtime and historic data.

Answer 5

Regarding possible other users: assign IP to each individual mac address from the base station manager and/or try radius.

As stated above, your base station should have logging capabilities. Else snort could be set up to watch for alien connections, I believe.

Answer 6

I'm using ProteMac Meter for monitoring my network activity:

ProteMac Meter is a network traffic logger. It monitors and records all Internet and network activity on your Mac computers. ProteMac Meter worked out as a traffic monitoring tool is essential for maintaining a safe network and diagnosing network and Internet connections and speeds. Meter’s easy to read network traffic details make reporting a snap. Download a free trial version of ProteMac Meter today!