Triple-Play Service Deployment

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BPON uses time division multiple access (TDMA) over two
downstream wavelengths and one upstream wavelength. It
typically provides 622 Mbps shared among up to 32 users. EPON
uses one wavelength for downstream and one wavelength for
upstream traffic and offers up to a symmetric 1.25 Gbps service.
BPON has evolved into GPON which utilizes the same wavelength
plan but delivers up to 2.5 Gbps of bandwidth shared among up
to 64 users.
Point-to-Multipoint Networks
As previously discussed, a PON network usually is a point-tomultipoint
network (P2MP). This means that although there is one
fiber at the OLT, the other end of the distribution network can have
up to 32 fibers under the same optical network. This is facilitated in
the PON through use of a passive optical component called a splitter.
Input
I 1
Figure 3.2 Schematic diagram of a splitter
Optical Splitter
Chapter 3: Deploying and Troubleshooting Fiber Networks
O 2
Output
The splitter allows for one port at one end and up to 64 ports at
the other end. Therefore, a signal sent from one end possibly can
be distributed to 64 customers simultaneously. This application is
ideal for video distribution. For data and voice, the use of time
division multiple access (TDMA) enables customers to receive and
send exactly what they choose, without knowing what other
customers are receiving and sending. Additional technologies
such as WDM PON are under investigation for point-to-multipoint
networks. The most attractive alternate is wavelength division
multiple access (WDMA) which dedicates a particular wavelength
to each customer.
O 3