RE: Extending IPCP for Route Table Entries

> From: Doug Kehn <dkehn@xxxxxxxxxxxxx>

> >From the outset, it has been acknowledged that this proposal duplicates what
> could be done with a routing protocol.  The argument for the duplication is
> that a routing protocol is "seen" as overkill when all that the Service
> Providers are wanting to do is add a single (okay...maybe two) static route
> entries on an interface.  Another factor to consider is the realization that
> CPE cost is being driven down to that of a dial-up modem.  Cost reductions
> are mainly realized through using lower density flash/RAM (when dealing with
> 100K+ magnitude every penny counts).  Lower memory density means that
> features must be removed/reduced as every byte counts.

Are you sure that even a penny would be needed for the at most 2000 
instructions needed to implement the fragment of RIP required to
have the same effect as the proposed IPCP option?

Could you justify the implicit claim that it would cost more in the
CPE to implement the necessary fragment of RIP than to implement the
same functions with the propsed IPCP option?  I suspect that in fact
the IPCP implementation would require more code, because there are
more corner cases.  For example, you don't need to handle configure-Naks
and and configure-Rejs in the RIP case.  Both cases require the same
changes to the CPE's routing table.  Both require the same sanity
checking of the route itself.

Given the reported popularity of software n CPE that is not known for
its small size, such as Windows CE, worrying about 100 lines of C or
2000 machine instructions seems misplaced.


> Also, Service Providers (I'm referring to broadband) use PPP because it
> provides accountability and authentication.  It also resembles the familiar
> dial-up model.  However, a problem arises as PPP termination moves off the
> PC and on to the CPE.  The CPE now becomes a router but is straddled with a
> point-to-point WAN interface when what is really needed is a networked
> interface.  I don't see (my opinion of course) Service Providers moving away
> from PPP because of the cost already invested in a PPP infrastructure.

What is a "networked interface" and how does it differ from at "point-to-point 
WAN interface?"  Both seem to involve PPP.


> At the expense of duplication could another method be found to solve the
> problems.  If the Route-Add option isn't appealing, maybe reconsider Option
> 144 (Subnet mask) again.

I can't find any such option in http://www.iana.org/assignments/ppp-numbers


Vernon Schryver    vjs@xxxxxxxxxxxx