On Tue, 26 Jun 2001 10:28:16 -0400 (EDT) Chris White wrote:
The other would be to Wholesale the last mile connection to the ISP customer. In this scenario you need to hand off the end user traffic to your ISP customers. DHCP alone is not a viable option in this model. How do you get the end user traffic to the ISP and back in a pure IP environment? Policy routing, GRE, MPLS, force your ISP customer to interconnect at every location, etc.?
Hello Chris; You provide frustrating few details and a statement "DHCP alone is not a viable option in this model." Could you restate more concretely what is your design problem which can only be solved by ATM/MPLS/PPPoE? I hesitate to answer for fear that there is some constraint I don't know about.
At this point ATM and PPPoE become considerations each with its own advantages. If the service offering is business class ATM may be preferred (required by your customer) for COS/QOS. From a configuration management standpoint PPPoE has advantages especially in a residential environment as you do not need to reconfigure the PVC when the end user changes providors.
What follows is not directed at you personally, but you happened to say the wrong thing at the wrong time :) Apologies in advance. <rant> I don't believe any of this "ATM is the way to do" COS/QOS crap. I have had it in my face for 10 years (my graduate work in the early 90's was performance of IP over ATM. This just in: it sucks.) IPoATM has never worked; prove to me it will work, then we can talk. Same goes for MPLS, with knobs on. Fat pipes; big buffers; simple protocols; get out of the way. </rant> We avoided doing DSL (much) until Etherloop and Ethernet was available because ATM sucks so much. I don't have much sympathy for people who decided otherwise. They knew, or should have known, the problems with the ATM pvc approach. If IPoATM worked; Ethernet would have been dead long ago.
In a wireless environment this becomes even more of a consideration as most of the current hardware is limited in ATM or L3 functionality...
I am sincerely sorry you are stuck using broken hardware. As a person who has thrived by deliberately passing up "the latest thing" until the proper hardware was available to implement good designs, I urge you to question your assumptions about whether using broken hardware is a good idea.
I do not intend to argue one technology over another, just to point out that there are reasons PPPoE exists and is in use.....
Reasons don't equate to good reasons :)
A good network design also needs to consider the business model of the company it supports.
I couldn't agree more! But the converse of that is true; the business model of a network company should reflect good network design. I believe the only workable model for networking companies is to have network engineers involved at the highest levels. That is, they have to have veto power over decisions. I don't understand how people think they can thrive in an industry in which they do not have at the senior level deep knowledge of the product. My undergraduate degree was in English; my graduate degrees are in CS. I worked for nine years at BBN before starting this company. Our COO was an a EE and a practicing network/compuer engineer for years before he got his law degree. Our CFO was a CPA, but has been in the commercial Internet business since its inception (ANS/AOL/UUnet). Technical experience works for us, while I note success does not seem to be widespread in the industry. regards, fletcher