Media for Pix debug, get more out of it

Hi, I am quiet newbie on PIX. Debugging, I got it.

I've been told it is GRE traffic becasue of proto=0x2f

Well, could you point me to URL detailling the content of a debug like that? Like a guide how to get more out of a debug.

Thank you,

Alain

--------- PACKET ---------

-- IP --

10.10.186.10 ==> 10.10.166.10

ver = 0x4 hlen = 0x5 tos = 0xc0 tlen = 0x30

id = 0x773 flags = 0x0 frag off=0x0

ttl = 0xff proto=0x2f chksum = 0x756

-- DATA --

00000010: 00 00 08 00 45 c0 00 18 07 72 00 00 | ....E....r..

00000020: ff 2f 07 6f 0a 0a 42 01 0a 0a 56 01 00 00 00 00 | ./.o..B...V.....

00000030: aa | .

--------- END OF PACKET ---------