What is PON and GPON in Optical Network?

[ChEeSe FaV]

I have recently started learning about the optical networks. Let me tell you that I am not having enough idea about it. Now we have given an assignments in which we have to explain about the PON and GPON. I am not having any idea about it. Since, you guys explained me very well last time, I thought to post here instead of wasting my time on Google. Hope that you will explain me properly this time too. I want to get an idea about what is PON and GPON in Optical Network? Thanks in Advance for your help..

[BlackNGold]

PON means Passive Optical Networks / Passive optical networks whereas, GPON stands for Gigabit Passive Optical Network. A passive optical network is a fiber optic network, which works for signal distribution without any active components. It works with optical splitters that have no electrical switching functions. Passive optical networks are installed in the area between the exchange and local loop to fiber gigabit connections. They function as access networks for the participants to the worldwide data and communication networks. GPON is a fiber optic system has the ITU in 2003, "capable G.984 Gigabit passive optical networks" called standardized. A variant of this is GEPON. Also standardized by the IEEE and mainly used in Asia. GPON is the successor of ATM-PON, and BPON (G.983). The standards are written by the ITU.

[Kerwin]

We distinguish between passive optical networks based on a point-to-point architecture and a point-to-multipoint architecture. The abbreviation for Passive Optical Networks PON (passive optical networks) has become a synonym for PtMP topologies, for example, although a PtP Ethernet passive optical network. That is, if PON is talk, then to a passive optical network with PtMP topology is meant.

In a point-to-point architecture, each participant viewed from the exchange from its own fiber, which ends with him in the apartment. Because participants own fiber is laid for each, allows management and service for each participant to unbundle. Thus, a PtP topology is technology independent. Each participant can choose a different provider on its fiber and its own technology. A subsequent upgrade is easy. PtP with suppliers can respond more flexibly to the changing demands of customers.

[B_Hodge]

A disadvantage is the high number of ports in the network nodes. For each participant has its own fiber, which must be supplied. In a point-to-multipoint architecture, each participant has its own fiber, but only until the next street cabinet. There is a passive optical splitter, which splits the signal from a fiber from the exchange, all participants glass fibers. The advantage of PON (PtMP) need fewer ports in the exchange and thus less space and energy requirements for switches. In a PON network for the unbundling of cable service and is more difficult because several participants here share a line. The introduction of a new technology is difficult because they must take place for multiple participants in one go.

[Quattro]

GPON is a passive optical fiber network that requires no expensive active components. GPON is based on the fiber optic infrastructure to a point-to-multipoint topology. From a central switch from which participants will be provided. The individual users are served via passive optical splitters, which act like prisms. The light signal is dispersed to multiple outputs. About the mote must 32 or 64 users a bandwidth of 2.48 Gbit / s (2.5 Gbps) downstream and 1.24 Gb / s (1.25 Gb / s) to share in the upstream. The advantage of passive optical networks are the lower cost compared to fiber optic networks with active components. The GPON network architecture is relatively simple and based on the star-shaped cable installations in the fixed network. In the exchange an OLT (Optical Line Terminator) installed. From there, a fiber optic cable runs to the distributors who are at the roadside. In a passive optical splitter distributor road is installed. The PON Splitter is a purely passive component. He needs no power supply. With the splitter, the signal on 32 or 64 fibers are branched, which run to the participants. At the end of the fiber, ie on the client side, an ONU (Optical Network Unit) and an ONT (Optical Network Terminator) is installed. Usually, the ONT is integrated into the ONU. The ONU is the terminal for the customer. This optical modem can be easily constructed and inexpensive. The distance between client and agency may be up to 20 kilometers. GPON works so well in rural areas.

[Rixwel]

The optical splitter distributes the downstream signal (transmission signal from the central office) to 32 or even 64 outputs. This means that all participants receive the same signal. So the data intended for the other participants. This eavesdropping is not possible, the data is individually encrypted with AES. The recipient can decrypt only the data for which he has the key. Conversely, directs the splitter, the upstream signal (transmitted signal from node) continue only in the direction of mediation. Downstream and upstream are handled by different wavelengths. Downstream runs at 1490 nm, 1310 nm upstream GPON can also use two fibers. One for the downstream and one for the upstream. Then there is only one color (1310 nm) is used. Unlike Ethernet works synchronously GPON. Downstream the data by time division multiple access (TDMA) are assigned. If needed, the OLT participants allocate different number of time slots, and adjust the downstream bandwidth dynamically. If the network operator provides this and just enough bandwidth is available, a participant could receive at least theoretically, nearly 2.5 Gbit / s of bandwidth allocated. Which implies, of course, that the other side in the network can deliver data as fast. The synchronous operation may have the advantage that the network operators reserve bandwidth to guarantee Quality of Service.