according to this old thread
https://bitcointalk.org/index.php?topic=10860.0, the usage is very low around 2mb per hour, you can build a huge farm and still consume very low
bandwidth is never a problem with mining, initial investment, consumption/cooling and space are the real problem
thanks for this., i always wondered how much bandwidth does the ASIC uses, at my place internet goes down frequently.
i wonder what hapens when internet goes down, does the ASIC keeps mining or just goes haywire ?
The bandwidth requirements are very negligible. However, keep an eye on the latency times to your pool (I'm assuming you will use one).
High latency times will increase the number of stale blocks which are just wasted effort. Perhaps set up a quick and dirty script to watch ping times.