ETHERNET PASSIVE OPTICAL NETWORKS
Passive Optical Networks bring optical fiber to the end users. It is a promising last mile broadband solution offering point to multipoint access. Ethernet Passive Optical Network (EPON) is emerging as a network access technology. The three main factors responsible for making it so popular are high bandwidth, low cost of components and low cost of maintenance. EPON provides connectivity between the Central Office (CO) and the end user. It is defined by ITU’s G.983 standard and supports triple play services .i.e. convergence of voice, video and data over a single network
Emergence of EPON can be traced back as the result of 3 drivers- The deregulation of common carriers (local loop) among telecom service providers, decline in cost of Ethernet and optical fiber and finally the growing use of internet.
The use of fiber optic cables has been evolving from backbone to WAN’s to MAN’s and soon to Local loop. On the other hand Ethernet has progressed to MANs and WANs besides LANs. This similarity in convergence will only prove advantageous to the communications Industry as they will be able to reap the benefits of both Ethernet and Fiber Optics.
Most PON solutions available in the market today are ATM based. EPON is currently finding its market in access portions of public networks. Although EPON is still in its rudimentary level in terms of deployment, it can be a viable option considering the fact that more than 90% of the network interface cards installed today are Ethernet cards. Not to forget the economies of scale, maintenance of Ethernet cables are much cheaper than copper wires and passive networks do not require any active component to be installed and taken care of. The only concern, however regarding the performance of Ethernet PON is the absence of a built in QoS mechanism.