PON Extra Material

Switches vs. Routers Fedex Example Fedex Kinkos Office: Routers Fedex Network of Fleets: Switches

Switches vs. Routers Switches create a network. Routers connect networks. A router links computers to the Internet, so users can share the connection. A router acts as a dispatcher, choosing the best path for information to travel so it's received quickly.

Routers

Switches Switches will forward incoming packets according to a MAC address.

Ethernet Patent

GPON (Gigabit Ethernet Passive Optical Network)

GPON Architecture G.984 There are several primary components of a last-mile PON -- the OLT, the fiber and splitters, and the ONU: OLT (Optical Line Terminal) - located at the CO, the OLT interfaces with the metropolitan network. The main functionality of the OLT is to adapt the incoming traffic (Voice/Data/Video) from the metropolitan rings into the PON transport layer.    ONU (Optical Network Unit) and ONT (Optical Network Termination) - ONU and ONT are basically the same device – ONT is located at the customer premise, and ONU is located outside the home. ONU receives optical signal and converts it into an electrical signal for use in the customer premises.  PON Splitters - With a single PON splitter, 32 subscribers can be served with two-way ATM. This way, it is not necessary to include a lot of add/ drop multiplexers and install the dreaded OSP cabinet. The PON splitters can be arranged in star, ring, or tree configurations to increase reliability.

Advantages of GPON Networks The clear advantage of PON networks generally is that a single shared optical fiber can support multiple users through the use of inexpensive passive optical splitters. In GPON networks, up to 64 ONTs can share one fiber connection to the OLT. This makes GPON an attractive option for service providers wanting to replace copper networks with fiber, particularly in high-density urban areas. Other advantages and features of GPON networks include: Standardized by ITU-T G.984 (Class B+). Operates at 2.488 Gbps downstream and 1.244 Gbps upstream. Practical fiber split ratios up to 1:64 (standard supports up to 1:128) The downstream channel is broadcast to all ONTs. The upstream channel uses time division multiplexing with a dynamic bandwidth allocation mechanism. Distance between OLT and ONT/ONU can be up to 20 km. GPON specifies QoS and management protocols required for triple-play services over the network. Downstream security guaranteed with 128-bit AES encryption. No active equipment in the access network, preventing problems from electromagnetic interference or lightning. Reduced equipment and fiber at the central office.

High-bit-rate digital subscriber line (HDSL)