traffic by using GPON encapsulating method. (GEM). 2. GPON fundamentals. Active transmission equipment in GPON network consists only of Optical Line. FTTH GPON – Learn FTTH in simple and easy steps starting from basic to advanced GEM (GPON Encapsulation Method) supports both native TDM and Data. EPON and GPON are popular versions of passive optical networks (PONs) GPON also uses a generic encapsulation method to carry other.

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The next section describes GPON key technologies. It is the data transport scheme in the specified GPON transmission convergence layer.

GPON Fundamentals – Knowledge Base

This is called Ranging. PON and fiber infrastructure can also be used for supporting any one-way distributive service. Each upstream encapsulatiom contains a number of transmission bursts coming from one or more ONUs. GPON adopts two multiplexing mechanisms- a in downstream direction i. The downstream transmission, i.


GEM provides a connection-oriented, variable-length framing mechanism for transport of data services over the passive optical network PON. The splitters are designated as [n: The optical network terminal ONTwhich is connected to the OLT at uplink side for service network interface, has many user-network interface ports.

In some existing CATV operator network or some telecom upgrading projects eg The Flag field allows the upstream transmission of physical layer overhead blocks for a designated ONU. Subscriber 3 in Figure 3 In the downstream direction, the OLT removes the outer tag or passes through the traffic to proper GEM port based on the tag value and priority bits. Your reliable fiber network equipment and service provider: The downstream GTC frame provides the common time reference for the PON and the common control signaling for the upstream.


For example, Un-fragmented Ethernet frame as shown in the following illustration. Each allocation interval is controlled by a specific allocation structure of the BW map.

However, if a client on campus as students, hostels, schools, colleges, hospitals, or corporate offices, where there is already CAT-5 copper cable is laid, ONU can serve as a more appropriate ggpon.

In case, any one fiber out of these two fibers is cut the ONU can be accessed through other fiber. Downstream Traffic Management Figure 6 shows a sample model of downstream traffic management.

The Plend is sent twice for redundancy. The upstream GTS frame contains multiple transmission bursts. PON system may be symmetrical or asymmetrical. GEM Frame Header detail. Each Ethernet is mapped to encapeulation single or multiple by fragmenting GEM frames. This T-CONT is of best-effort type and mainly used for data services such as Internet and services of low priority which do not require high bandwidth.

Key Technologies of GPON:GEM | FTTH & Triple Play Broadband equipment

DBA allows upstream timeslots to shrink and grow based on the distribution of upstream traffic loads. Because the access network is shared, ONU upstream transmissions could collide if they were transmitted at random times.


Link protection is also known as link aggregationwhich can protect the link and the same time, it can aggregate the traffic as well. GPON supports triple-play services, high-bandwidth, long reach upto 20kmetc.

It is then transmitted in the downstream direction to the PON interface by using a scheduler.

It is a recipient of upstream bandwidth encasulation within the ONU. If the ONU has no traffic to send, it transmits idle frames. The ONUs then act upon the relevant information contained therein.

Key Technologies of GPON:GEM

In the upstream direction, it is used to bear the service traffic. DBA is a methodology that allows quick adoption of users’ bandwidth allocation based on current traffic requirements and it is especially good for dealing with bursty upstream traffic. The optical paths can vary between 2 to Each GEM port bears one mmethod of service traffic i.

The Port ID ranges from 0 to The GEM channels carry variable-length Ethernet frames. The Optical Splitter merely divides the optical power into N separate paths to the methld. The OLT may allocate as much duration as it needs in the downstream, upto and including all of the downstream frame.