----- Original Message ----- From: "Fletcher E Kittredge" <fkittred@gwi.net> To: "Wojtek Zlobicki" <wojtekz@idirect.com> Cc: <nanog@merit.edu> Sent: Tuesday, June 26, 2001 2:52 PM Subject: Re: Cable Modem [really good network design]
On Tue, 26 Jun 2001 14:27:29 -0400 "Wojtek Zlobicki" wrote:
The Ethernet protocol was designed to adjudicate and route packets internal to one homogeneous, physical network. It handles media access, security, reliablity and routing in that one physical network.
What does Ethernet have to do with routing ?
Routing in its original sense. You stick an Ethernet frame in here, it traverses a number wires connected by boxes which make decisions as to which wire it should go out on. It then pops out on the other edge of the network. Magic!
A network of Ethernet switches looks a heck of a lot like routers. They are certainly smarter than the IP routers of circa 1983.
The problem you dont really have one physical network. We are trying to extend Ethernet into a logical network.
Who is "we" in this statement?
Those using PPPoATM/E
The reason that I like PPPoATM is that the end device requires littel intelligence , it knows one PVC, and all changes (linking them to the ISP of choice, propogate easily downstream)
Little intelligence to implement ATM? Never heard that claim before.
Much easier to place a $300 CPE (Cisco 678 which speaks ATM). Than a 1605 (chosen for the fact that its about the cheapest Dual Ethernet Router from Cisco). How do you propose that we bring Ethernet to the customer ? The now defunct CLEC that I worked for, used 678 and 1483 so that the 1605 did the routing (as far as our netowork was concerened, we were bridging/switching these customers, the fact that they ran IP was their business).
Contrast the cost of an Ethernet chip with an ATM chipset.
ATM to the desktop never took off, whats wrong with Ethernet over ATM ? With devices such as IADS, it allows for easy differentiation of traffic. Now you can cary voice and data over the same physical link without worry. ATM is expensive in the core but inexpensive at the customer prem ($300 for a ATM DSL modem is relativel cheap, especially since it is a router , if you want it to be).
.RFC 1483 (Ethernet over ATM, used in DSL and plausibly in cable ) is a great idea for business but not suitable for home users. Hardware that you speak of becomes just too expensive.
Define "great idea". Compare and contrast with all the failed DSL providers which used ATM. Use one DSL/ATM provider who is making money as an example. No excuses please.
Market GLUT and not technology failed here. I was able to completely reprovision a customer in about two minutes in a PPPoATM network we ran. PPPoATM allows for a easily managable resale strategy, if your sales staff and wholesalers can't sell the service, thats not the fault of the technology.
How do you reconcile the cost of the hardware being too expensive with the statement above that ATM requires little intelligence?
It appears as if someone has thought of this before Someone is
doing this already (I don't know the name of the company), taking regular cable modems and using wireless for intramodem communication (why re-invent
apparently the
wheel) instead of copper.
That would be a good idea.
regards, fletcher