Ethereal-dev: Re: [Ethereal-dev] improvement proposal for displaying tunneling protocols
On Sun, Oct 27, 2002 at 05:48:36PM -0500, ETC WAJU wrote (in HTML mail,
unfortunately; not everybody's mail reader handles HTML mail
conveniently, so plain-text mail is preferred):
> In the packets of those tunneling protocols such as GRE, GTP, L2TP, etc,
> there are two pairs of IP addresses, inner src/dest addresses, and outer
> src/dest addresses.
>
> Right now in Ethereal 0.9.7, the upper display window only show the
> inner src/dest IP address, it is only possible to see the outer IP
> address in the lower display window when expanding all the details.
>
> To my opinion, it is more important to display the outer src/dest
> addresses than the inner src/dest addresses, because it can give a
> quicker view of the tunnel src and dest.
Not everyone would necessarily agree with you on that; somebody might
care more about the traffic being tunneled than the tunnel itself.
> - In the upper display window, show outer src/dest addresses instead,
As per the above, that would not be the correct answer for everybody.
> or add another two columns to show outer src/dest addresses which should
> be put in front of the columns showing inner src/dest addresses
You're assuming here that there will never be more than two layers of
IP; the chances that there will be N layers of tunneling probably go
down quickly as N increases, but they probably don't drop to 0 at N = 3.
However, showing the innermost and outermost layers is probably enough
for most users, so either
1) separate column specifications for the innermost and the
outermost addresses (which a user could configure if they
wanted them; I suspect most users wouldn't want them, as
they're useless if no tunneling is being done, and most
captures rprobably don't have tunneling, so I wouldn't make
that the default)
or
2) an option to control whether address fields should show the
innermost or outermost address
would probably be useful.
