Audience: IT Technology Management I
As Technology continues to shift at a rapid pace in the area of IT, as leaders we often need to step back and have a mind of wonder much like that of a child. We must try to drop our guard from the multitude of concepts that we are comfortable with and look at what is going on around us and then ask questions. In doing this exact thing, I asked myself why has the enterprise not yet began to adopt GPON over the traditional LAN configuration that we have been deploying now for over 10 years?
GPON is short for Gigabit Passive Optical Network. The GPON network delivers broadband services to network devices without employing active electronics between the Optical Network Terminals (ONT) situated at the end-user location and the Optical Line Terminal (OLT) generally situated in the Main Distribution Frame (MDF). A fiber-optic cable connecting the OLT and ONT is used to carry a wavelength downstream. By using a passive splitter the downstream data originating from the OLT can be distributed as part of a point-to-multipoint architecture. The upstream data running from the ONT to OLT – which is delivered on a separate wavelength to avoid collisions with the downstream transmission is aggregated by the same passive splitter unit, which also carries out the recombining function. This enables data to be collected by the OLT over the same single fiber that sends the traffic downstream. GPON supports bandwidth of
2.4Gbps downstream and 1.2Gbps upstream that can be shared between up to 64 ONTs or end user locations. This is actually better than the bandwidth provided by the traditional workgroup switch solution. Here, the LAN is engineered with massive over-subscription which is generally configured for 1Gbps for every 48 users.
In my research I have found that a GPON solution can have several advantages over a traditional workgroup switch approach for providing the LAN services inside the office building. Hardware costs are reduced by eliminating the need for workgroup switches in every riser closet which equates to an esimatd saving of 25%. Installation is less expensive, because an individual fiber optic cable run will support multiple end devices from the ONT, as opposed to the router/workgroup switch approach that requires a CAT5e/6 cable run for each end device on the network. This topology can potencially yield a cost savings of up to 75%. Saving in space is then realized by the reduced size and quantity of equipment required in each riser closet. Power consumption is greatly reduced due to the elimination of workgroup switches and environmental controls in the riser closets which in turn positively impacts maintenance costs that are minimized due to the reduced number of “active” components in the network and the five 9's reliability of the GPON equipment. Additionally, the fiber infrastructure has a 25 year life expectancy vs. 7-10 years for copper. This means construction is reduced due to the elimination of power and environmental controls in the riser closets. Currently there is a 90M (295 feet) distance limitation for a CAT6 cable run, more than one riser closet may be needed on a floor to reach end devices; potentially doubling the construction costs on each floor.
Through research and reading further I have discovered that GPON is a mature, thoroughly tested carrier class technology that has been around for the last five years and is currently deployed in real world mission critical facilities. Intelligence, Homeland Security, National Research and DoD facilities are currently using GPON. The commercial and civic sectors are making aggressive moves towards its adoption.
The greatest advantages I see to deploying GPON technologies within the LAN environment are, the elimination of active electronics within the infrastructure, its ability to bring fiber to the desktop efficiently,