0x1–0xFFFFFFFF ( milliseconds )
0x6DDD00 ( 7,200,000 milliseconds = 2 hours )
Determines how often TCP sends keep-alive transmissions. TCP sends keep-alive transmissions to verify that an idle connection is still active.
This entry is used when the remote system is responding to TCP. Otherwise, the interval between transmissions is determined by the value of the KeepAliveInterval entry.
By default, keep-alive transmissions are not sent. The TCP keep-alive feature must be enabled by a program, such as Telnet, or by an Internet browser, such as Internet Explorer.
Windows 2000 does not add this entry to the registry. You can add it by editing the registry or by using a program that edits the registry.