Are AFS file transfers encrypted?

[jackt123@gmail.com]

Hi all! I've been using arla on FreeBSD 5.4 very happily.

:)

Someone from my lab asked me if the files transfered
via AFS are encrypted or not, so I googled but I can't
find a clear answer...

1) I know the Kerberos auth is encrypted, and that the tokens
are encrypted. But can people sniff or even modify
filedata that I'm reading?

2) If so, how is the encryption established?
With SSH, I had to click YES the first time
I connect to a server (to trust the public key is not tampered).
But with Kerberos and AFS, I never had to do that.
Can someone help clarify for me (or point me to where
to read more)?

Thanks so much!

a trusted public key" first... But I never had to