I have got packets lost about 5 packets or more continous over L2TP VPDN connection when I ping (at 32bytes packet size ) from a PC that connects over L2TP to LNS ip address at ethernet, loopback or WAN. On the same time, I have got NO packet lost on another PC that connects over PPP to LAC (RAS) when ping to the same LNS ip address.
Here is network diagram.
[PC]---{PSTN]---LAC------<WAN>------LNS---[LAN]
For LAC I use C3660 IOS 12.1(5) T8 , LNS is C1750 IOS 12.1 (10a)
Thank you.