"If the actual bandwidth of the link between the hosts is 10Gbps, the optimal TCP Window size would be (10,000,000 bps / 8 bits/byte) * 0.5 sec = 625 Kbytes."10,000,000 bps = 10Mbps, not 10Gbps.
I have the same issue with IP phone 8941 upgrading its firmware. Current firmware is App Load IDSCCP 9-3-1-19Error is:[07:17:26, 09/20/2013] upgrade SCCP8941_8945.9-3-2SR1-2.bin3.sgn fail (read fail) Have you found solution?