Slow performance over a WAN connection

  • 3032853
  • 11-Dec-2007
  • 26-Apr-2012


Novell Client for Windows 2000/XP/2003 4.91 Support Pack 4
Novell Client for Vista 1.0.0 File Access


Performance over a WAN link seems slow. When transferring files using NCP (using the Novell Client), performance is slower than when transferring files using CIFS (without the Novell Client). A packet trace reveals that the packet stream from the client to the server is smaller (fewer TCP/IP data packets are transferred before an ACK is required) with NCP than with CIFS.


Increase the NCP TCP receive window on the file server. The setting on the server is "NCP TCP receive window" and the supported values are 1400 to 65535. Because the default is only 23360 bytes, the client will only stream this number of bytes, creating more TCP overhead for the NCP connection. Over a WAN connection, this can impact performance. This parameter can be set (and checked) in Monitor, by using the console "Set" command, or in the startup.ncf file.

Monitor: "Server Parameters" ->"NCP" ->"NCP TCP receive window"
Set: set ncp tcp receive window = 65535