need help about ppp+ssh

[yawl]

I know the question may be too old,but I am confused by it for a week,
I really need some people to help me:

I am now going to set up a VPN with PPP and ssh on my Linux.
But after reading lots of documents(including VPN howto,and other
things)I still get lots of problems.  At last, I solved most of them, the PPP
device appeared on both sides, route table is set correct, HOWEVER, I can not
ping them through. I am really confused about this situation, and can not get
helpful information on the web.If somebody have some experience of ssh+ppp
VPN solution,I hope you can give me some hints. Maybe a detail explanation of
the ssh & PPP mechanism would help me.

Thank you very much.
yours yawl

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