There are three type of EVC. Point-to-Point : In a Point-to-Point EVC (E-Line), exactly two UNIs must be associated with one another. Multipoint-to-Multipoint : In a Multipoint-to-Multipoint EVC (E-LAN), two or more UNIs must be associated with one another and all should be root node. Rooted-Multipoint : In a Rooted-Multipoint EVC (E-Tree), one or more of the UNIs must be designated as a Root and each of the other UNIs MUST be designated as a Leaf.A root can send packet to all other root and leaf node but leaf node can send packet to only root node.