i am using Parallels Desktop 3.0 build 5608 (operating system is Mac OS X 10.5.4). for networking to my office, i'm using Cisco Systems VPN Client Version 4.9.0.1 (0080). from windows XP SP2 on a Boot Camp partition with some number of updates applied (i don't think it updated all the way to the recent SP3), i am having spotty connectivity. it would appear that connections that don't require a lot of data work fine, but connections that do require more data appear to hang. for example, using wincvs from my xp-sp2 VM, i can perform a diff on a file versus what's on the repository, but i cannot perform a cvs graph. i've been able to cvs update small files but not larger ones. my browser (firefox) seems to appear to start connecting, but hangs for most pages. i can telnet to a machine on the other side of the VPN, and i can even keep entering commands in it for a while (it never hung). i've tried creating a custom macOS location for my machine, and for that location, i've tried dialing down the MTU for each of the Parallels items so that whatever NAT wrappers surround the packets have room. but that was only a guess, and does not appear to have helped, though i could dial these down further (they are 1386 for my AirPort card, 1272 for en2 as created by parallels, and 1158 for en3 as created by parallels), or i could see if there's something similar i need to do to the TCP/IP interface inside my xp-sp2 VM. any help would be greatly appreciated.
I believe that the best solution will be Bridged Ethernet and Cisco VPN client in Windows XP. You are correct NAT interface is wrapping packets, and this may be cause, also you can try solution in http://kb.parallels.com/en/4809
bridged ethernet? i guess my follow-up question then is: if i am using bridged ethernet to tunnel into parallels, can i also still use the VPN from the mac os session? both need to have VPN access to the corporate network. if the bridged ethernet will allow me to get to the wireless access point running NAT, then that indeed ought to be good enough.
