The article I read said that they actually tested the transfer speed from the DNC to elsewhere in Washington, and it couldn't come close to the speed the files show to have been transferred at. I think the point was to show it could not have been done by "Russians" because it was impossible to get an international internet connection to transfer any faster than the local one they tested.
The article I read said the speed was very consistent with the transfer time to a local media thumb drive.
The notion from the article I linked is that 2 GB in 87 seconds is impossible. That is clearly untrue. I did it in 26 seconds from an ordinary server in NYC to one in Dallas. Both are garden variety virtual servers that can be set up and run by any kind of hacker, or they locate offshore. It won't affect the speed.
I don't know what data center the DNC used, but it's very likely they got better internet service than my $5/month servers.