Hi everyone,
I'm attempting to decode some IPv6 packets with ethereal 0.8.19.
I encoded them by hand and I'm using text2pcap to generatea tcpdump file.
It appears that ethereal works out the IP protocol version by
looking at the link layer (layer 2) protocol field. eg for
PPP, it is looking for 0x0021 (IPv4) versus 0x0057 (IPv6).
This works OK generally, but I can see a couple of problems;
Firstly, one of the link types you can specify to text2pcap
is "raw IP" (12), but there is no way to view IPv6 through this.
Secondly, for IPv6 or IPv4 (or any other layer 3 protocol)
over MPLS, there is a protocol value for MPLS unicast, 0x0281.
There is no information in this about IPv4 versus IPv6. So
presently it seems there is no way to decode IPv6 over MPLS.
Is this all correct?
Shouldn't it be possible to look at the IP version header to
determine IPv4 versus IPv6? For MPLS, there will still have
to be an assumption that it's IPv4 or IPv6, but that would
be better than assuming v4.
thanks,
Hamish
--
Hamish Moffatt VK3SB <hamish@xxxxxxxxxx> <hamish@xxxxxxxxxxxx>