The following shows how long it takes to transfer 1 Terabyte of data across various speed networks:
- 10 Mbps network : 300 hrs (12.5 days)
- 100 Mbps network : 30 hrs
- 1 Gbps network : 3 hrs
- 10 Gbps network : 20 minutes
A full set of sample requirements is available in this table.
Note that on a high-speed network it takes less time to transfer 1 TeraByte of data than
one might expect. It is usually not necessary to try to get 900 Mbps out of a 1 Gbps network
if you only need to move 1-2 TB of data per day.
(and in fact your disk is likely to be the bottleneck at this point anyway).
In general it is not a good idea to try to completely saturate the network, as you will likely end up
causing problems for both yourself and others trying to use the same link.
For example, if you
know your receiving host is connected to 1 Gbps ethernet, then a target of speed of 150-200 Mbps is
reasonable. You can adjust the number of parallel streams (as described on the tools page) that you
are using to achieve this.
If there is a T3 (45 Mbps) link in the middle of your path, then your target speed should be
no more than 10 Mbps. However most DOE labs and large universities are connected at speeds of at least
1 Gbps, and most LANs are at least 100 Mbps, so if you dont get at least 20 Mbps, there may be a problem
that needs to be addressed.
