Extending Ethernet over MPLS Networks

Ethernet started out as a local area network protocol, but is quickly becoming the metropolitan area network protocol of choice. It offers easy interfacing to existing wired and wireless business networks, rapid bandwidth scaling without equipment changes, and a lower cost structure than traditional telecom services. If Ethernet is so great for the LAN and MAN, how about Ethernet for the WAN?

Ethernet WAN is enjoying a rising popularity, especially among companies with multiple business sites located across the United States and across international borders. You can get dedicated point to point wired Ethernet connections between any two locations, but a competing methodology that is gaining steam is Ethernet over MPLS.

Why use an MPLS network to transport your Ethernet traffic? The first reason is that MPLS networks are already in place and going where you want to send your traffic. Sure, you can custom engineer a dedicated private line service, but why re-invent the wheel? Ethernet is easily transported over MPLS networks using Pseudowire encapsulation that emulates the wireline it competes with. Which do you think is going to be less expensive? Paying for a custom point to point wireline connection or being one stream of traffic on a large MPLS network?

The way it tends to work out is that short haul Ethernet links have the cost advantage when implemented as dedicated lines. This is especially true if you are nowhere near an MPLS carrier node. Once you start looking at coast to coast transport or a situation where you want multiple Ethernet LANs connected in a transparent mesh network, MPLS networks gain the advantage. MPLS also has the edge when you want to cross international borders to include foreign sites on your corporate network.

Carriers may be muddying the water even further by offering Ethernet line services that consist of copper or fiber Ethernet access connections to their MPLS network core, where the long haul Ethernet transport really takes place.

There are several types of Ethernet services that are really popular right now. One is E-Line or Ethernet Private Line service. This is a standardized service specified by the MEF (Metro Ethernet Forum). It gives you a Carrier Ethernet connection that bridges two LANs. A variation is EVPL or Ethernet Virtual Private LIne. What EVPL does is let you use a single physical Ethernet port to connect to multiple Ethernet private lines going to out to geographically diverse locations. This is something you could use to replace a star network built on independent wireline connections to those same remote locations.

Another popular service is E-LAN or Ethernet LAN service, also called VPLS or Virtual Private LAN Service when implemented on an IP/MPLS network. While Ethernet Line Service replaces dedicated point to point telecom lines, Ethernet LAN is a meshed network service that interconnects multiple locations on an any-to-any basis. With VPLS, you bridge your multiple LANs so that they act as one giant LAN network. That’s true even if you have a hundred or thousand sites in the U.S. and and equal number spread out over the globe.

What carrier can offer this level of MPLS networking? Actually, there are several to choose from. If one can’t serve all your sites, multiple carriers can share traffic through a E-NNI or Ethernet Network to Network Interface to reach all locations with VPLS or E-Line connections. If you need this type of connectivity, you may be surprised by how affordable it has become recently. Get Ethernet over MPLS service prices now and see how far your network can really reach.

Benefits Of An MPLS Mesh Network

Once your business has expanded to include additional locations, like branch offices, offsite data centers, factories or warehouses, you need a way to get all those locations on the same network for data, voice or both. The latest and greatest way to do that is the MPLS Mesh Network.

Companies with two locations don’t generally start off with an MPLS network. What they do is buy a point to point T1 line or Ethernet Line service to link the locations. T1 is the traditional P2P telecom service. Ethernet line service is newer and offers the ability to link two LANs at the layer 2 switching level.

So, who needs an MPLS network for two locations? Maybe you do. The reason isn’t that you need the multiple site connectivity that MPLS makes easy. It’s a matter of cost. Depending on the availability of T1 or Ethernet point to point service, you might be better off getting T1 or Ethernet last mile connectivity to a much larger MPLS network. The major incumbent and competitive carriers have regional, nationwide or international service footprints. If your two locations are across the country rather than across town, it’s conceivable that taking advantage of an MPLS network for the long haul span might actually have a cost advantage.

Now, let’s consider the business with 3 or more locations. You can still use the point to point line strategy to link them. If you try to create a mesh network with P2P lines from each location to every other location, you’ll find this topology gets pretty expensive pretty fast. What many companies have done is create a star network with point to point lines radiating out from company headquarters to each remote location. All traffic gets routed through HQ regardless of where it is going.

When you do this, you are effectively becoming your own WAN network provider. It has the advantage of giving you complete control of the network on a instantaneous basis. But it costs you the staffing needed for constant vigilance and the need to establish new long distance P2P lines every time another location is added. The cost goes up linearly as you add locations because there is no economy of scale when it comes to dedicated point to point data lines.

Where you do get economy of scale is by sending your traffic over a privately run MPLS network. All those P2P lines are replaced by access network connections at each location to be served. The lines are only long enough to reach the carrier's local point of presence, and priced accordingly. The carrier then sets up paths through its core network to interconnect your locations as you specify. You can specify which locations can connect to which other locations and how much bandwidth they have available. The MPLS connections can be set up as fully meshed so that every location can interact with every other location.

Beyond that, MPLS networks can easily handle fully converged voice, data and video networks so that you can include your telephone service and video conferencing on the same network. That can be an enormous cost saver for companies with business sites spread over many states, or with international locations included.

Are you paying too much to run your own wide area network to link multiple business sites? Get the quality and performance you require and enjoy a significant cost savings as well when you switch to an MPLS Mesh Network.