Passive Optical Networks

is resolved by adding a random delay before each ONU transmits the Register

frame. It is also possible for an OLT to receive multiple valid Register frames in a

discovery window.

2.7.7 Point-to-Point Emulation (P2PE) in EPON

Ethernet MAC interfaces are interconnected with Layer-2 (L2) switches or

Layer-3 (L3) routers. L2 switches directly interconnect network devices on the

Ethernet layer and are therefore more efficient, less costly, and easier to manage

in a LAN environment. On the other hand, routing is used in a wide area network

to interconnect multiple Layer-2 networks [13]. In an Ethernet environment, L2

connection is achieved using IEEE802.1 based bridges

8

or switches [31, 32]. An

Ethernet switch forwards the traffic among its multiple ports. ...