Michael,
In my experience (I didn't read the definitions you pointed us to Timbo), LANs are small networks connecting COMPUTERS within one facility over one interconect medium (wire or fiber). (I'll stay away from the different protocols you can run over the media). These are usually confined to a fairly small area (say one building) because length restrictions and a maximum number of conncections are required to guarantee a certain level of service. LANs can be extended to other LANs within the same or other buildings within a campus environment via "bridges and gateways", thus allowing all the computers to talk. This is usually referred to as an "Extended LAN". When you have gateways from a LAN to outside carriers that tie into other LANs (e.g., perhaps belonging to the same corporation and) perhaps in other cities or other parts of the world, you have a (corporate) WAN. These days most LANs also provide access to the Internet, typically via a high-speed (e.g., dedicated T1) link to a local ISP.
Given these descriptions (which anybody can take issue with), I don't understand what technolgy DCI brings to the table (??). Outfits like Cisco and 3Com are the big players in this computer networking arena. Does DCI provide hardware "gateway" technology from the LAN to the outside carrier OR is it just providing the outside (leased/DCI owned) line that connects to other parts of a WAN? If it's providing hardware, where is it manufactured, etc.? Do you agree LANs & WANs are limited to the interconnection of computers? A "network" of locally connected telephones (e.g., within a building) is uaually referred to as a PBX (Private Branch Exchange) or-- if outside access is allowed -- a PABX (Public Access Branch Exchange), right?
I guess I also don't understand the terminology of "switch" as DCI uses it. A switch can be anything from a big AT&T #5 ESS "switch" which preforms all the call switching (routing) within a central office for a large city to the switch necessary to service the PBX traffic for a small office area. Unfortunately, IMO, the term can take on so many meanings, it doesn't mean much of anything anymore. For example, I could understand a CyberFax gateway also being referred to as a switch.
Given all this, can you tell us what DCI means by switch and what role you play in LANs & WANs? Does "buying a switch" mean DCI is buying switching (routing) hardware or are you really just buying long distance lines?
If I sound confused, guess that's because I am (and more questions came up as I kept writing) (g).
TIA,
Dan |
