Search This Blog

Thursday, July 24, 2008

Metro Ethernet Or MPLS - Which is the Best Choice For Your WAN (Wide Area Network)?

By Michael Lemm

If you could choose only one technology for your wide area network ..... metro ethernet or MPLS .... which would you choose and why?

Keep in mind this is not a simple bandwidth solution question. Such as choosing "how much" .... between say DS3 bandwidth or OC3 bandwidth. This goes to the heart of designing your network infrastructure.

First off ..... you need to understand that they are not mutually exclusive. I would use Metro Ethernet as an access technology .... and a Layer-3 technology, such as MPLS, for my backbone. The appeal of MPLS is the Quality of Service (QoS) capabilities it offers.

The bottom line when choosing a WAN technology is the price compared to bandwidth and redundancy capabilities. Service providers offer various flavors of similar technologies, so unless you have the specifics, its difficult to compare.

Be conscious of the fact that when you deliver WAN services to a remote site, you will always be relying on a local exchange carrier (LEC) to deliver the "last mile" services. Most problems with WAN circuit outages at remote offices are physical layer issues at a CO that is the LEC's responsibility. This is of particular importance if you need to deliver services in a city or rural area with a dated infrastructure. In this regard appropriate vendor selection could actually prove more important than technology.

Indeed these are not necessarily mutually exclusive - there are technologies such as VPLS which is a Metro Ethernet version of MPLS. The number one factor is what do you NEED? Are all of your sites that need this connectivity within a metropolitan area and is there a single provider who is offering Ethernet access to all of these locations? If the answer is "no", then the choice is clear - MPLS, which is fairly ubiquitous these days.

MPLS is more appropriate for a diverse network with multiple connection speeds and multiple stakeholders, especially in situations where you're looking to achieve CBR. Metro Ethernet is best used in more of a "bridge" (I use the term loosely!) situation, connecting physically-separate offices where everyone is engaged in similar work or at least working for the same division. The reality, of course, is that a typical installation consists of Metro Ethernet interconnects and an MPLS backbone, but I said "choose one".

From my perspective it would have to be MPLS, purely for the flexibility of access methods and transports supported, the scalability of bandwidth demands, and of course, the QoS and traffic prioritization capabilities. Again, the use of MPLS does not preclude MEN, but MPLS would be my overarching choice if pushed.

In sum, sadly, like many computer networking questions, the answer is, "It depends."

Michael is the owner of FreedomFire Communications....including Michael also authors Broadband Nation where you're always welcome to drop in and catch up on the latest BroadBand news, tips, insights, and ramblings for the masses.

No comments: