Historically, since 1980s, Ethernet has evolved from a Local Area Network (LAN) protocol running at 10 Mbps over a shared coaxial cable to a latest networking technology running at speeds up to 10 Gbps over all manner of copper wire and optical fiber in networks extending worldwide. As the Ethernet popularity become larger, Service providers offer variety of carrier Ethernet service to extend these network beyond the ‘LAN’ boundary into Wider access network environment, metropolitan area network (MAN).
As the network growth further, Multi Protocol Label Switching (MPLS) has become a great player for enterprise client to perform network interconnect between branches. MPLS Layer 2 point-to-point is an option for those whom require huge bandwidth for their network. Dedicated line will be physically planted at the clients dedicated places get link each other.However, the limitation of this giant trunk is that the service cannot go for point-to-multipoint services. Whilst, for those require lower bandwidth at their large number of sites, they would go for MPLS layer 3 IPVPN , which normally operates as a partitioned private network constructed over a shared IP-based backbone that utilizes technologies to ensure privacy of data.
Nonetheless, due to mega growth today in Data and video sharing, Service provider start to offer new service could comply on the huge multi-point transfered content. Virtual Private LAN Service (VPLS) would be a great player for such of those requirement. VPLS is a type of layer 2 VPN. In a VPLS, the Ethernet LAN at each customer site is extended as far as the edge of the provider network. The provider network then emulates the function of a LAN switch or bridge to connect all of the customer LANs to create a single bridged (Ethernet) LAN. One of the main differences between a VPLS and a MPLS point-to-point service is that the VPLS provides a point-to-multipoint service at layer 2.
VPLS has significant advantages for both service providers and customers. Service providers benefit because they can generate additional revenues by offering a new Ethernet service with flexible bandwidth and sophisticated service level agreements (SLAs). VPLS is also simpler and more cost effective to operate than a traditional service. Customers benefit because they can connect all of their sites to an Ethernet VPN that provides a secure, high speed and homogenous network. Moreover, VPLS provides a logical next step in the continuing evolution of Ethernet from a 10 Mbps shared LAN protocol to a multi-Gbps global service.