Silicon Investor (SI) -- The First Internet Community

STOCKTALK

We've detected that you're using an ad content blocking browser plug-in or feature. Ads provide a critical source of revenue to the continued operation of Silicon Investor. We ask that you disable ad blocking while on Silicon Investor in the best interests of our community. If you are not using an ad blocker but are still receiving this message, make sure your browser's tracking protection is set to the 'standard' level.

Technology Stocks : LAST MILE TECHNOLOGIES - Let's Discuss Them Here -- Ignore unavailable to you. Want to Upgrade?

To: ajs who wrote (3532)	5/3/1999 4:07:00 PM
From: TheSlowLane	Read Replies (1) \| Respond to of 12823

ATM vs. IP The following article was written by Grant Holcomb, Chief Technology Officer at TeraGlobal Communications (TGCC). TeraGlobal is working on a solution that will deliver converged networks (voice, video and data) to the desktop. I believe that TGCC is positioning themselves to be a major player in this field. The availability of broadband last-mile solutions is definitely a pre-requisite for them to be successful. Enjoy... Asynchronous Transfer Mode (ATM) Versus Internet Protocol (IP) When the very first telephones were installed the telegraph industry scoffed at this new technology and labeled it irrelevant. The telegraph empire with all of its capital investments, dependencies, relationships, customers, and large highly skilled labor force could not possibly be wrong or obviated. ATM is to IP what the telephone was to the telegraph. First of all it is not technically correct to compare ATM to IP. ATM is a transport layer technology and IP is a communication protocol. An ATM data stream consists of "cells" of equal size. An ATM cell is always 53 bytes long. The first 5 bytes of every ATM cell defines its destination and purpose. In contrast, an IP data stream consists of variable length packets. Each IP packet has a header which can be from 20 to 60 bytes in length. An IP packet can be any size from 21 bytes to a maximum of 65,535 bytes. Just like an IP packet gets sent over an Ethernet transport layer in a local network, an IP packet can be divided into ATM cells and transported over a medium that supports ATM. In fact, over a highly distributed network it is now cheaper, faster, and more reliable to send IP over ATM. It is also true that any communication protocol can be seamlessly and simultaneously mixed over an ATM data stream (for example SNA, Novell IPX, Digital's DECNet, and AppleTalk). This implies the ability to support legacy applications while taking advantage of the real-time nature and quality of service guarantees that ATM offers. It is very easy to prove the advantages of ATM through an analogy. Imagine if Federal Express moved packages from New York to San Francisco like IP packets are moved over the Internet. You would have all different size, weight, and shaped boxes arriving at unpredictable times. If too many packages arrived at once the shipment of every other arriving package would be delayed. The receiving center would need a very large highly skilled and expensive labor force. This is particularly true because every package must be opened and its contents analyzed before a decision on how to proceed can be made. As the packages are moved across the country they would have to stop in every city and each and every package would have to be opened again. The contents of the package must be inspected before the package can proceed to the next city on its journey to San Francisco. By the time the package arrives in San Francisco you can be assured that all perishable items are beyond their expiration date. However, imagine if Federal Express moved packages like data can be moved via ATM. Unimaginable efficiency can be achieved. Every single package would be the exact same size, weight, and dimension. Every package would arrive at a scheduled time. On the outside of every package is a computer readable address label allowing it to be automatically sent to its destination. The path the package would take between New York to San Francisco would be private, secure, non-stop, direct, and always take a defined amount of time. The "ATM" Federal Express would have a fraction of the labor force, lower overhead, greater profitability, and be able to deliver "Quality of Service" guarantees on package delivery the "IP" Federal Express will never be able to deliver. Compare the cost and performance of a high end ATM switch from Fore Systems to a high end IP router from Cisco. Moving lots of 53 byte packets on an ATM switch requires a fraction of the computational power, memory, and lines of operating code in comparison to a dramatically more expensive, slower, higher latency, labor intensive Cisco router. The "Holy Grail" of communications is to eliminate the barriers of time, distance, and cost. As long as the industry focuses on the IP standard as the smallest logical element of data transfer these barriers will remain. IP Routers are "dinosaurs" in comparison to ATM switches. Considering the processing power that exists in a desktop computer let the recipient of the ATM cells determine what to do with the arriving data. The real-time two-way ATM cells that arrive can contain literally anything - an IP packet stream, live video stream, live audio stream, AppleTalk stream, etc... all nearly simultaneously. In the time it takes a desktop computer to place a 1,500 byte IP packet into a memory buffer for processing, 28 ATM cells could be opened feeding a real time video stream, real-time audio stream, file download, and email download nearly simultaneously. The future of communication is to take ATM to the desktop. This does not obviate IP, it just puts IP in its true place as a data store and forward technology. IP is not the provider of next generation real-time two-way communication the incumbent IP monopoly would have the market believe.