Metro Ethernet Service – An Introduction to Basic Concepts

Metro Ethernet services fall under two basic concepts, both of which are in regards to the method in which data travels. These include wholesale and retail, with a retail service being a private line. This is a more traditional approach whereas wholesale denotes bulk, so it is a service in which a large Ethernet “pipe” is sold to various customers – generally many of them.The scenario doesn’t differ much for either of these services in its basic form, in other words the way in which the Ethernet is structured and the equipment it uses is no different. Traffic between customers does not get confused as each service is isolated. Each customer receives a well-defined SLA through their transport pipes depending on which circuit or packet has been paid for.It is only when switching and multiplexing is applied to the packets which makes things different. EOS and RPR are two instances in which the methods of Ethernet transport differ. For multiplexing clients, they share the same bandwidth and this is controlled and boundaries created by “packet queuing” whereas switching clients have their own pipe. The chief difference is that the boundaries in multiplexing are maintained by means of logic, this ensures definition or QoS.The service provider ensures that they identify each client’s traffic in the network pipe if it is shared and they also identify and enforce the appropriate services to each client, depending on the bandwidth purchased. These guys (the service provider) are also able to transparently move each client’s traffic to various locations (transparent LAN) if the need arises and they are also equipped in the process of customer scaling. This is vital to ensure that every customer receives the packet they are paying for and deployment of a VPN as well as any-to-any connectivity is applied.Ethernet technology is Local Area Network technology or more commonly LAN, and is the widely used type of LAN. LAN was originally used by Xerox on a system called Alohanet, which was originally in operation at the Palo Alto Research Center. After realizing its usefulness it was develop more so DEC and Intel pitched in with Xerox to further this development. Most typically, coaxial cables are used and this cable is built from specifically twisted wires. Is the most commonly used and it provides10Mbps transmission.The speeds of Ethernet vary and from 10BASE-T it increases in speed to 100BASE-T for 100Mbps speeds, 1000BASE-T, and so on. There is also 1 Gigabit and 10 Gigabit Ethernet, and these are unbelievably fast, but they do have a place in LAN technology.The man who takes credit for developing, and the naming of Ethernet is Robert Metcalfe, he named it after the “ether” that light transmitting substance which helps pervade the entire Universe with light. The synonym works very well and the “Ethernet” is cabling which allows the entire network (universe) to be pervaded with data.Robert Metcalf invented Ethernet as far back as 1973; hard to believe isn’t it? Originally it was called DIX, because of the collaboration between Digital, Intel and Xerox, and today is it standard protocol as a medium of communication.