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Article #25540: Configuring TCP parameters on Windows95/98

Problem:
How can I set the client to detect a lost connection 
quicker.

Solution:
In some cases it is desired to configure the TCP settings on 
a system to create a better environment for connections in InterBase.  
In InterBase v5.x on the Windows platforms and other platforms 
where the TCP layer supports keepalives, InterBase depends on 
the TCP layer to manage keeping the connection open when there 
is no activity on the part of the server.  The TCP parameters of 
interest are:

  KeepAliveTime - Specifies the connection idle time in 
  milliseconds before TCP will begin sending keepalives, if 
  keepalives are enabled on a connection. 
  The default is 2 hours (7,200,000). 

  KeepAliveInterval - Specifies the time in milliseconds between 
  retransmissions of keepalives, once the KeepAliveTime has 
  expired. Once KeepAliveTime has expired, keepalives are sent every 
  KeepAliveInterval milliseconds until a response is received, up 
  to a maximum of MaxDataRetries before the connection is aborted.
 
    The default is 1 second (1000). 

  MaxDataRetries - Specifies the maximum number of times a segment 
  carrying data or an FIN will be retransmitted before the connection is 
  aborted. The retransmission timeout itself is adaptive and will vary 
  according to link conditions. 

    The default is 5. 

The parameters do not not normally exist in the registry, and must be 
placed in the following location:

  Hkey_Local_Machine
   System
    CurrentControlSet
     Services
      VxDMSTCP

Set your browser to the following location to pick up a document from 
the Microsoft online Knowledgebase on how to configure these registry 
entries:

  http://support.microsoft.com/support/kb/articles/Q158/4/74.asp

Last Modified: 26-OCT-00