Subject: re: Is there an IPCP extension negotiating Def Gateway Addr

From: "Dan Malone" <[email-masked]>
Date: Wed, 03 Dec 1997 13:06:54 -0500

All :

To everyone who responded to my previous post (see below).. I was trying
to solve a very specific problem and thought I may have missed something
in my search. I am by NO means advocating we start a discussion that DGW
addressing be included as an option to IPCP. I am network protocol savy
enough to know there are well established ways of getting the DGW
address and I fully agree it should NOT be part of IPCP. My intention
was to check with the group to see if it had overlooked a discussion or
implimentation because of RFC1877.

Thanks to all who responded.. I will retreat to the cave to pursue
another route to solve my problem !

Best regards,

Dan Malone   [email-masked]

From: "Dan Malone" <[email-masked]>

> Just a shot in the dark.. I have looked through all of the PPP related

> RFC's and RFC Drafts and have not been successful in finding anything
> relating to negotiation or just plain forwarding of a default gateway
> address.  Is there an obscure RFC/draft that addresses this.. has
there
> been any discussion relating to this type of scenario ?? Any
information
> positive or negative would be greatly appreciated.

---

From: [email-masked] (Vernon Schryver)
Date: Wed, 3 Dec 1997 17:41:36 -0700

> From: Philip Rakity <[email-masked]>

> There is no IP address of the peer if the link is unnumbered nor do most
> ISPs respond to RIP

Please recall the old and neverending IPCP address negotiation
discussions.   Please name two PPP implementations that really run the
link unnumbered, which is to say that they do not (eventually) send an
IPCP Configure-Request containing their own IP address.  As James said,
that IP address can almost always be used as a de facto default IP route.

>From what I've seen, most PPP boxes used in situations where
the PPP peer needs an IP gateway address do understand RIP, albeit
often less than perfectly.  Even bridges can be said to understand
RIP since they will blindly forward RIP broadcasts and multicasts.
It is fairly common for ISP's to send RIP default routes over PPP
links just in case the peer needs one.

It is true that most ISP's don't care to play RIP with their customers,
but they generally do like to play IPCP Address games.

> ...
> > That this and similar questions (e.g. concerning DNS servers) keep
> > coming up (and worse, getting mis-solved by various big outfits that do
> > not understand IP, PPP, DNS, and the rest) says that there should be a
> > PPP RFC that tells people what PPP is not.

We really need an RFC that points out that practically no IP/PPP link
in the real world is completely unnumbered, and that the peer's IP
address is usually the right answer for synthesizing a static default
route and even for sending UDP packets to port 53.

Vernon Schryver,  [email-masked]