Friday, May 13, 2005


The world of computer networking is filled with acronyms and these four happen to be in order. Can you guess how?

OK, that's pretty easy. It's by distance from near to far. The only one of these that hasn't been around for ages is PAN or Personal Area Network. PANs include Bluetooth, USB, UWB (Ultra Wide Band) and FireWire. A personal area network is intended for your personal use to interconnect electronic devices you are using. Bluetooth is emerging as the king of wireless personal area networks. If your cell phone and laptop computer both have Bluetooth enabled, you can get Internet access for your computer via Bluetooth from your cell phone that is connected to an EV-DO or GPRS data network.

Most everybody has a LAN or Local Area Network now. There once were many protocols for connecting computers, printers, and telecommunications networks within the corporate environment. Eventually everyone migrated to Ethernet with TCP/IP. That has gelled to the point where every new technology had better have IP connectivity, at least at the edges. The standardization around the Internet Protocol and Ethernet has promoted an economy of scale to the point where you can buy a 10/100 Mbps Network Interface Card at Wal-Mart for under ten bucks.

Every PC and many printers now come with Ethernet ports standard. Most portable devices support the Wireless version of Ethernet, Wi-Fi, which is also termed a Local Area Network. A LAN is intended for use within a room, building or area. WiFi's range of around 300 ft. puts it into this category.

Within an office or corporate campus, networking revolves around the LAN or LANs running on CAT5, CAT5e or CAT6 copper wiring with some spans of fiber optic cable and some wireless LANs. When you leave the LAN, you enter the world of MANs and WANs.

MAN is Metropolitan Area Network. It's intended for use within a city. A typical example is a SONET Synchronous Optical Network that is set up as a pair of fiber optic rings within the business district of a city. The reason for a pair is to provide redundancy in case one of the rings fail. The other takes over within 50 msec, perhaps so fast the outage isn't even noticed by many users. You get to the MAN with an access network connection. That may be an OC3 or OC12 fiber optic link or a T1 or T3 service.

Note that SONET is a different protocol than Ethernet. With some fancy bit handling, Ethernet can be formatted to be carried by SONET, T1, T3, or other digital networks. The Ethernet packets can be split up to fit the requirements of the carrier and reassembled at the other end.

Going cross-country you are using a long distance carrier called a WAN or Wide Area Network. A WAN can connect MANs together or simply connect a group of individual locations. The Internet is an enormous WAN. You can get WAN service from a variety of competitive carriers with speeds from T1 at 1.5 Mbps up to OC48 at 2.5 Gbps or even OC192 at nearly 10 Gbps.

Most WANs are TDM or Time Division Multiplexing based because that is the standard adopted by the telephone carriers that first implemented them. Since much data is now packet based using the IP standard, carriers are now offering native IP based networking connections in many areas. That means that your LAN data never changes protocol. It leaves your router as Ethernet, traverses an Ethernet WAN, and hooks to another LAN some distance away. To the IT manager it all looks like one big corporate LAN, even though a common carrier provides the link between sites.

GigaPackets is our service to help you get the best pricing on the T1 through Fiber Optic Network Connections you need. Our team of technical consultants will be happy to discuss your MAN and WAN networking requirements at any time.

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