Installation guide

Fiber Solutions
FTTH Application Guide
13
subscriber by reducing the number of optical transceivers in the optical
deployment network.
In contrast, Active Ethernet dedicates optical transceivers at both the OLT and
the ONT for each subscriber with a point-to-point topology. This simple fact
gives Active Ethernet the flexibility for longer reach and can be better suited
for rural settings, where subscribers may be up to 50 miles from a central
office. Further, because Active Ethernet dedicates an optical fiber for each
subscriber, it is also well suited for the guaranteed bandwidth requirements of
business subscribers.
GPON with class B+ optics provides a maximum of 2.5 Gbps downstream
and 1.25 Gbps upstream traffic. GPON is a point-to-multipoint architecture
which may be split up to 64 subscriber ends, so the 2.5 Gbps downstream/1.25
Gbps upstream is split among the subscribers. All information is sent out to all
units. Encryption keeps information private.
Active Ethernet provides a dedicated symmetric 1 Gbps performance
upstream and downstream. Since Active Ethernet is point to point there is no
splitting/sharing of bandwidth per OLT port. However you can also share an
Active Ethernet link by using an Ethernet switch instead of an ONT in the
subscriber end of the connection. The difference from GPON to Active
Ethernet in this case is that GPON does not require active components (like
Ethernet switches and SFPs) to share the bandwidth in the subscriber side of
the connection, which makes GPON cheaper to implement to multiple
subscribers.
Under ideal circumstances, GPON can reach up to 20 or 30 km, however the
practical limit is 12 km (about eight miles).
By comparison, under similar ideal circumstances, Active Ethernet can reach
80 km or nearly 50 miles.