What is the lowest enough speed for mining?
Internet connection speed will not impact your mining process. This is depending on the number of machines you are using for mining or the number of clients hashing. Look up the stratum (open source client-server) protocol, and you can find out about how much bandwidth each client will consume for the process.
What you said is correct but the main point is that what ever internet connection to be used but it should be stable one because if the connection is not stable then the the reward block cannot process fully and it will be cancelled so like this you wont be able to earn any thing. So stable connection is the more important in the mining process. Like what other user told 128 kbps is also enough to run the mining until the connection is more stable.
i beg to differ.... i though any internet connection would be fine so i went with ethernet over powerline 1.2 gbps wall adapters and an 8 port gigabit switch to run eventually 6 rigs. i was initially impressed with the ethernet over power, pretty effin convenient and cheap i must say, with an impressive dl speed of about 35 mbps and upload of about 12 mbps (on a 150 mbps service) ...both numbers should be more than enough.... i spent DAYS trying to figure out why my 7 x 8gb EVGA GTX 1070 SC was mining ethereum @ +/-25 Mh/s when i should've been closer to 200 Mh/s! many many hours wasted then i said "maybe its the internet connection, naa everyone says it doesnt matter much...o well lets get a wifi dongle and see"! (LOL) same rig now mining ether @ 212 MH/s!!!! so the internet in this case did matter and if anyone knows why my hash rate was effected do drastically using ethernet over power please advise!
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