 suitable for service-centric networks namely E-Line, E-LAN and E-Tree [24,29,37]. 7.4.2.3.10.1 Ethernet Line (E-Line) E-Line is a point to point service offered using a single EVC (Ethernet Virtual Connection) over MEN (Metro Ethernet Network) as shown in Figure 7.21. An EVC is an instance of an association of two or more UNIs6 (user network interface). EVC is a logical entity which helps to visualize Ethernet connections. EVCs are the building blocks for Ethernet service architectures like E-LAN (Ethernet LAN), E-Line and SO on. Three types of EVCs are defined: point-to-point, point-to-multipoint (rooted multipoint) and multipoint-to-multipoint EVCs. The two classes of services that are offered using E-Line service type are Ethernet Private Lines (EPL) and Ethernet Virtual Private Line (EVPL). EPL replaces TDM private line and is created using dedicated point-to-point EVC. EPL allows single EVC at each UNI. This limitation is overridden in Ethernet Virtual Private Line (EVPL) where the EVC bandwidth is shared. EVPL supports service multiplexed UNI, that is multiple EVCs per UNI are supported. EVPL replaces Frame Relay or ATM services. 7.4.2.3.10.2 Ethernet LAN (E-LAN) E-LAN provides multipoint connectivity, connecting a set of customer endpoints, giving the appearance to the customer of a bridged Ethernet network connecting the sites as shown in Figure 7.22. E-LAN service is used to create multipoint layer 2 VPNs (virtual private networks). E-LAN services offered on Carrier Ethernet network are Ethernet Private LAN (EP-LAN) and Ethernet Virtual Private LAN (EVP-LAN). Both EPLAN and EVPLAN support dedicated or service multiplexed UNIs. E-LAN is the foundation of IPTV (Internet Protocol TV) and multicast network applications in Carrier Ethernet networks. 7.4.2.3.10.3 Ethernet Tree (E-Tree) E-Tree is rooted to point to multipoint service. The two classes of service that are offered via E-Tree are Ethernet Private Tree (EP-Tree) and Ethernet Virtual Private Tree (EVP-Tree). Both EP-Tree and EVP-Tree provides traffi