not that I really know, but a couple of thoughts increase the TCP window size, and enable the selective ack feature.
increasing window size allows for the transmission of more data whilst waiting for acks. the selective ack feature supposedly allows for selectively acknowledging packets within a TCP window. I'm not sure I understand the docs, but here it is: http://www.cisco.com/univercd/cc/td/doc/product/software/ios121/121cgcr/ip_r /iprprt1/1rdip.htm#1019734 watch the wrap scroll up and down for the various ip tcp commands and what they do.! ""Jerry Deer"" wrote in message news:200211091728.RAA26351@;groupstudy.com... > puts this problem into words better in case my email dont make sense. > Portion of article below: > ***Unavoidable half-second delays as signals bounce off the satellites can > wreak havoc with IP Security because it takes so long for TCP > acknowledgement to get back to the sending machine. TCP interprets the > satellite delay as network congestion and throttles back its sending rate, > meaning the IPSec VPN traffic gets through but at a much slower rate than > the link could actually support.For non-VPN traffic satellite providers get > around this problem by spoofing the acknowledgements using devices that are > placed between the satellite base station and the customer's sending > machine. TCP on the sending machine perceives no congestion and sends at the > fastest rate the satellite link can bear.*** > > Hello All, I have a remote location that I have had a satellite installed at > by Skycasters. The internet connection i get with this is great by itself > with bandwidth around 600 - 700k ( we paid extra for better connection) . > Well the whole reason for this connection was to run vpn over it but as soon > as we put a vpn firewall or software solution on this connection we get > about a 56k connection. Of course skycasters now says oh you want to run > vpn? it will cost an extra 1400 bucks and and additional XX.00 amount per > month and we will hook you up with SUPER VPN! here is what they say on their > site. > ----------------------------------- > ......Due to the Asymmetric nature of satellite internet, certain > applications do not perform very well over satellite, regardless of whether > used in a VPN, SuperVPN or in the clear. SuperVPN is not a not a cure-all > for satellite-related performance issues, it simply is a way to use VPN > without the traditional severe VPN-induced degradation. It does not increase > whatever level or speed of service that would be available for a particular > protocol/application above the level found if the application/protocol were > to be used "in the clear"............. > ------------------------------- > > I am hoping someone with simular experience with vpn connection can shed > some light on this and tell me if i can do anything myself with router > configs , software solutions etc. etc. to handle this problem. ANY and ALL > replies will be greatly appreciated!! > > Thank you, > JD Message Posted at: http://www.groupstudy.com/form/read.php?f=7&i=57170&t=57170 -------------------------------------------------- FAQ, list archives, and subscription info: http://www.groupstudy.com/list/cisco.html Report misconduct and Nondisclosure violations to [EMAIL PROTECTED]
