Metro Ethernet :: essays research papers

Metro EthernetDisclaimer this is intended to be an introductory technical article certain details beget been excluded in the interests of space and clarity. Network design examples are presented to illustrate specific technical points and are not intended to fully complete.Historically unbalanceds (Wide Area Networks) and local area networks (Local Area Networks) have relied on in viewent technologies. At a physical layer WAN technologies today continue to be based largely on legacy TDM systems that were built initially to support voice, video and premature data communications in a reliable fashion. WAN bring togetherivity over distance often requires the use of regenerators and meet points amongst multiple Telco suppliers that may span the globe. Without strict adherence to standards, these connections would not function. WAN technologies depend on highly complex and expensive equipment, which can guarantee inter-operability and five 9s reliability required to support the mill ions of paying nodes utilizing the network.Meanwhile, the advent of early PCs and the recognition of the value in networking devices together gave rise to Local Area Networks. These LANs were developed from a business customer perspective, which placed more emphasis on costs and ease of use over reliability. There were a number of different competing LAN technologies, two of the near common being Token Ring (IBM) and Ethernet (everyone else). The triumph of Ethernet in the marketplace, to the extent where it is included in every PC, game console and some refrigerators, provides a consonant and relatively inexpensive way to build internal networks with relative ease. As the internal PC networks continued to grow and thrive a need to connect disparate facilities together resulted in development of bridges, gateways and ultimately routers for the sole purpose of connecting LANs to other LANs located anywhere from several miles to several railyard miles apart. These devices allow dis parate interface types to be connected by performing the necessary modifications to the signal and protocols to allow WAN and LAN equipment to understand one another. Because LAN Ethernet and WAN TDM networks were so vastly different in their technical make-up these intermediary devices were needed to allow inter-communication to occur. While the benefits of enterprise connectivity are great, they come at the cost of special hardware, software and application complexity as the speed of the network can change by a factor of 100 between a client and the server (100 Meg bit per second Ethernet to 1.5 Meg bit per second WAN).