Metro Ethernet is the familiar Ethernet protocol that we’ve come to know and love on our LAN networks. It’s not exactly the same, because it needs to be adapted to work over longer distances than typical building and campus runs. This, and other service enhancements, have been standardized by the Metro Ethernet Forum (MEF), an industry group comprised of over 170 companies and more than 75 service providers. The MEF has defined five attributes that distinguish what they call Carrier Ethernet from the familiar LAN based Ethernet. These are standardized services, scalability, reliability, service management and quality of service.
What carriers get is a set of certified network elements that work to connect users on a local or worldwide basis. They also have services that can be transported over whatever physical networks they have available, including legacy TDM networks originally designed for telephony.
Metro Ethernet is Carrier Ethernet implemented within a city or metropolitan area. Two of the popular standardized services are Ethernet Line Service, a point to point connection, and Ethernet LAN Service, a multipoint connection. Companies use Metro Ethernet to link branch office buildings, factories, warehouses, data centers and other locations in the area.
Ethernet can also be used as a last mile access connection to larger private networks or the public Internet. These links have traditionally been T1 lines, DS3 connections, or SONET/SDH fiber optic services. Ethernet is growing in popularity as a network access service because it is lower in cost and more scalable than legacy telecom services.
At the same time that Carrier Ethernet has soared in popularity, MPLS networks have seen a similar growth in demand. Most networks have a defined protocol that they run. This can be TDM, IP, Frame Relay, or something else. The beauty of MPLS networks is that they are designed to support all protocols. Hence, the name Multi-Protocol Label Switching. The label switching part has to do with a tagging system that is used to encapsulate and route packets while they are on the network. Since the MPLS network doesn’t need to use the internal packet structure for routing, it doesn’t matter what those labels are attached to.
Most new large scale networks are based on MPLS. It doesn’t matter what’s running as the core network. It might be IP. It might be SONET. What the user sees is a privately run network that can securely transport voice, data, video or converged network traffic within a city, between cities or around the world. MPLS networks have all but completely replaced the older Frame Relay networks that were once used to link computers over wide areas.
What you probably have guessed is that Ethernet and MPLS are very compatible. Many carriers have nationwide or international MPLS network service footprints. You can combine Ethernet access with a large MPLS network and create a very cost effective way to link your geographically diverse business locations.
Large scale Carrier Ethernet networks are also on the ascendency. A new interconnection standard called ENNI or Ethernet Network to Network Interface connects Carrier Ethernet service providers so they can share traffic and effectively increase their service footprints. The underlying transport networks may or may not be MPLS networks themselves.
What’s combination of Ethernet and MPLS offers the highest performance at the lowest cost for your applications? There are network consultants available right now to provide you with Metro Ethernet and MPLS service options and pricing at no charge for serious business and organizational users.
