Ethernet complex

Simplicity has long been listed among Ethernet's greatest charms. (I can relate.) But some of the same folks who can't stop praising Ethernet's simplicity are constantly imbuing it with ever more complexity.

They're forcing it to maintain quality of service functions and intricate interconnection tasks. They're teaching it how to tell time well enough to carry voice traffic in wireless backhaul networks. They're building sophisticated software to automate Ethernet provisioning. One of the newest entrants in the space, Ethos Networks, explains how it uses complex algorithms to create a metro Ethernet network so constantly self-aware that it can deny at its edges any traffic it knows might violate its service level agreements at any point inside. Think of it as a velvet rope for a technology better known for its big-tent appeal.

The services market is getting more complicated, as challengers such as cable operators further fracture the market. Others are pioneering new territory among small- and medium-sized business customers.

In last year's Guide to Carrier Ethernet, the man who coined the term Ethernet wrote that there was “a big danger in this carrier Ethernet effort that they're going to kill the goose that laid the golden egg.” I remember similar things being said of MPLS several years ago — that the label-switching technology originally designed to speed up routers was being overburdened and overcomplicated with too many traffic-engineering functions. It didn't stop MPLS from thriving. But at the same time, an entire equipment market has now cropped up offering relief from the excessive complexity of MPLS.

Provider backbone transport, or PBT, has been promoted as that simpler alternative in metro networks. A lot of that simplicity comes from PBT's nature as a point-to-point technology. But although the technology is still young, it's already graduating to multipoint applications, requiring sophisticated control planes to handle the added complexity (the ramifications of which you can read about on page 20). And in case you didn't get the parallel with MPLS, standards bodies renamed PBT PBB-TE for “traffic engineering.”

At the same time, efforts are being made to simplify Ethernet. The Metro Ethernet Forum is striving to make ordering wholesale Ethernet services as consistent and predictable as buying a T-1. The previously mentioned control plane vendors are offering to hide the complexity of Ethernet provisioning from the network operator. And equipment vendors, particularly in the PBT space, are working hard to establish interoperability, motivated as they are to make carriers more comfortable with Ethernet.

They'd better hurry along, before someone invents a new technology designed as a simpler alternative to Ethernet's complexity.