There is only one significant RFC covering SLIP, but there are dozens that cover PPP. Explain some of the reasons why PPP is more preferable than SLIP.  Describe what would be needed to use PPP as a...

There is only one significant RFC covering SLIP, but there are dozens that

cover PPP. Explain some of the reasons why PPP is more preferable than

SLIP.

 Describe what would be needed to use PPP as a VPN without tunneling

through a higher-layer protocol such as SSH.