Ethernet is a protocol that has been widely used in local area networks for many years, thanks to its low price, its increasing speed (from 10 Mb/s to 100 Gb/s) and its versatility (this protocol is available in both wired and wireless versions).
Launched in the early 2000s, its use for transport purposes by service providers required the addition of active service supervision, performance measurement and effective protection management functionalities, in order to be a credible competitor to existing technologies such as ATM or SDH. With the addition of these features, Ethernet, now Carrier Ethernet, has become an alternative that is just as reliable, cheaper and easier to upgrade in terms of throughput or functionality. Whereas ATM stagnated at 622 Mb/s, Ethernet interfaces are now capable of 10Gb/s. Ethernet also natively supports multipoint services, unlike SDH and derivative technologies (OTN). It has become the de facto standard for protocol level 2 in the OSI protocol layer, just as IP had become a few years earlier for layer 3.
To accelerate its development, equipment manufacturers and service providers have created a forum to provide specifications for Ethernet services and service interfaces. The Metro Ethernet Forum (MEF) has produced over thirty recommendations that enable operators and service providers to offer services that are compatible with each other, and thus simplify choice for the end consumer. These recommendations include :
interface specifications (user or inter-network) and service attributes ;
service definition for end-users ;
the definition of mobile or fixed collection services.
This article first describes the features of the Ethernet protocol and the additions made to transform it into an efficient service transport protocol. It then discusses the attributes defined by the MEF that enable a service to be defined. Finally, the various possible services will be described.