Refer to RFC 1122, 188.8.131.52.
1 millisecond to 60,000 milliseconds
Do not increase this value to more than 500 milliseconds.
Increase the value under the following circumstances:
Slow network links (less than 57.6 Kbps) with greater than 512 bytes maximum segment size (MSS)
The interval for receiving more than one TCP segment is short