If you are wondering how much bandwidth your network need for mining cryptocurrency, here’s the answer:
The speed of the network won’t affect the mining rate. If you have a modern computer you can forget about this issue. Regardless of what protocol mining bandwidth you use, stratum, GBT or another one.You will need only a minimal bandwidth for mining bitcoin and similar coins.
Of course, the above is primarily true for POOL mining. If you solo mine, you will have to run the full node. For example, on my Windows 7 I use something like 30 Mb per day of download, and 10 Mb per day of upload. Solo mining would be more intense in terms of traffic.