Metropolitan or Metro Ethernet Networks are based on Carrier Ethernet standards established by the Metro Ethernet Forum (MEF), and industry standards group. This ensures that you know what services you are getting and that you can directly compare these services from provider to provider. Why bother with Metro Ethernet when the MAN connections you have now are working just fine? While these services are no doubt running reliably and getting the job done, you may be missing out on service options that could better meet your needs. You many also be paying more than you really have to.
The core networking technologies of Metro E networks could be pure IP networks or they may be Ethernet services running on top of legacy SONET fiber optic networks. That’s a perfectly legitimate technical approach. Protected SONET rings have a history of high reliability, low latency and considerable bandwidth. As a user, having to deal with SONET at the SONET level does limit your options compared with Carrier Ethernet. You can be better off with Ethernet over SONET or Ethernet over IP core networks.
SONET is a TDM or Time Division Multiplexing technology with all traffic loaded into neat little time slots lined up one right after the other. An ADM or Add/Drop Multiplexer handles getting specific traffic on and off the network. Your connection is by one of the standardized Optical Carrier levels, such as OC-3 (155 Mbps), OC-12 (622 Mbps), OC-24 (1.24 Gbps) or OC-48 (2.5 Gbps).
Carrier Ethernet is based on packets rather than time slots. Packets are distinguished by the information in their headers that are read by switches and routers. This is the same Ethernet than runs on your company LAN. That’s the first advantage of Metro Ethernet. It’s directly compatible with LAN Ethernet so there are no inefficiencies from protocol conversions between dissimilar networks.
The other obvious advantage is interfacing. Connections to Metro E is a conventional Ethernet connector. At lower bandwidths, including 10, 100 and even 1000 Mbps, a standard RJ-45 connector can suffice. Higher bandwidths have fiber optic connectors.
Carrier Ethernet is designed to be both highly and rapidly scalable. You can generally get far more bandwidth options than are available with SONET levels. They are also easy to scale up and down. What sets the limit on your bandwidth is the port speed that you connect through. If you have a 100 Mbps port, you can specify any bandwidth up to 100 Mbps. With a Gigabit Ethernet port, you can get any bandwidth up to 1,000 Mbps. Likewise a 10 Gig E port lets you scale to 10 Gbps. The GigE port is very popular for this reason. You can call up your provider and move up from 200 to 400 Mbps in a matter of hours or days. There is no need to change hardware interfacing as long as you are operating below the maximum port speed.
Metro Ethernet Networks can give you the same point to point connections that you are getting now or a multipoint service that operates as a LAN extension. E-Line is an Ethernet Line Service. E-LAN is an Ethernet LAN service. E-LAN can run at layer 2, letting you connect multiple metro locations together in one large bridged LAN. This is a popular service for companies with multiple offices, factories, warehouses, retail outlets and so on within a given metropolitan area.
Can Metro Ethernet networking technology work to your advantage? Get network options and pricing for Metro Ethernet services to compare with your current connection setup.
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