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 : Cisco Systems, Inc. (CSCO) -- Ignore unavailable to you. Want to Upgrade?

To: Scott C. Lemon who wrote (12754)	2/28/1998 11:03:00 PM
From: Michael P. Michaud	Read Replies (1) \| Respond to of 77400

Scott, thanx for taking the time to respond to Claire's post... Again, I am getting quite the education on this thread Mike

To: Scott C. Lemon who wrote (12754)	3/1/1998 2:28:00 PM
From: Clare	Respond to of 77400

Hi Scott, thanks for the synopsis of "object routing", or "object caching". As you describe it, it is layer-7 routing, application-level coordination of where objects (or large streams of bytes that form the gif, file, etc). So this ICP (internet caching protocol) will run above layer 4 and will still need to be routed/switched between the cache servers and end users. If the cache servers were directly connected (and here we need definition), then the communication from a user to his/her default cache router still needs to be routed/switched. Now let's see what directly connected means. I'm supposing you mean direct Layer 3 connected, meaning that they are layer 3 peers. If you want to spread these cache servers over a large geographical area, you'll need WAN connections comprised of Layer 2 gear (switches). Directly connecting two router ports via gigabit etherchannel maybe gives you up to 10 kilometers (at best) of spread. I think you statement of today's packet routers are directly connected, you mean Layer 3 directly connected. Yet, entire infrastructure of Layer 2 devices are invisible to two routers who are peering across a WAN link. As far as they are concerned they are directly connected at Layer 3, but require infrastructure to spread them geographically. Finally, what I meant about connection-oriented is at Layer 3. IP is connectionless, TCP over IP is connection oriented. TCP sets up the connection to its peer on the other side. (NNTP, SMTP, etc. are all higher layer protocol). IP is the packets and they are routed connectionless. Each packet travels independently. What people are trying to do with Layer 3 switching is to set up flows or tags that will stream Layer 3 packets through the network so that once a routing decision is made for the first packet of the "object", or flow, the rest of them can be switched in hardware. Cisco already does this and has been doing this with Netflow switching on their high-end routers. No problem here for Cisco. Cisco is also working on tag-switching to tag an "object" in your terminology (or flow) so that the individual packets are switched on the same path. The way I see it, object routing will just run on top of Layer 2/3 switching/routing, so Cisco benefits anyway. The fact is, once your object hits the wire, it is "framed" or "packetized", or "sliced into cells", for transfer at lower layers.