NetUse Traffic Monitor
NetUse Traffic Monitor 2.1 for Mac could be downloaded from the developer's website when we last checked. We cannot confirm if there is a free download of this app available. The latest version of the application can be installed on Mac OS X 10.6.6 or later.
The most popular versions among NetUse Traffic Monitor for Mac users are 1.3 and 1.2. Please check the Mac app with an antivirus before launch as it is downloaded from the developer's website, and we cannot ensure that it is safe. This Mac app is a product of DewDrop Studios. NetUse Traffic Monitor for Mac is included in Internet & Network Tools.
From the developer:
NetUse Traffic Monitor provides the best way to monitor your network traffic on the Mac. Utilizing the SNMP feature of any modern Internet router or gateway, NetUse monitors and collects real-time Internet usage statistics for all the computers in your home or office that share an Internet connection.
If you have a traffic cap on your Internet usage, NetUse will help make sure you don't exceed your limits.
You may want to check out more software for Mac, such as SNMP Test Utility, Net Monitor Sidekick or Traffic Counter, which might be similar to NetUse Traffic Monitor.