Optical networks rely on optical fibers and other optical hardware to form the network of the Internet. Outside home or office, the power cable is usually connected to the optical cable, which provides the interconnection between the data center and the optical line terminal (OLT) of user's end. There are many optical network technologies, such as passive optical network (PON).

PON
A passive optical network (PON) is a fiber-optic telecommunications technology for delivering broadband network access to end users. A PON system can terminate in a variety of locations, including a subscriber's home, an office building, or a neighborhood "curb" or shared point. These terminations are described as follows:
· Fiber-to-the-premise (FTTP)
· Fiber-to-the-home (FTTH)
· Fiber-to-the-building (FTTB)
· Fiber-to-the-curb (FTTC)

A PON system consists of an optical line terminal (OLT) at the communication company's central office, several optical network units (ONUs) near end users, optical distribution network ODN and AN management module. Typically, up to 32 ONUs can be connected to a single OLT. 

A passive network does not involve any active hardware. This means only using passive hardware to carry, combine, split, filter, or otherwise to adjust the transmission signals. Thus, the optical distribution network (ODN) consists of only passive components, which are usually less expensive than active optical components. A PON has an OLT at a central control station and one or more associated Optical Network Units (ONUs) at user’s end. Between these two locations within the PON, there are some passive components to divide, combine and condition the signal.

EPON
EPON stand for Ethernet passive optical network. EPON is a competitive technology of GPON. EPON uses Ethernet packets instead of ATM (Asynchronous Transfer Mode) cells. EPON also uses Internet Protocol (IP) to carry data, voice, and video data. It generally delivers 1G symmetrical bandwidth, which makes it a popular choice. EPON is an emerging broadband access technology, which is used to access data, voice and video services. It can be a part of fiber to the home (FTTH) or fiber to the home (FTTP) PON.

GPON is based on a standard for new-generations of broadband passive optical access. GPON is widely deployed in fiber-to-the-home (FTTH) networks. GPON provides:
· Up to 2.5 Gbps
· Quality of Service (QoS) full business protection and advanced security 
· Full operations, administration and management (OAM) functions
· Ethernet access to user

GPON
GPON stands for Gigabit Ethernet passive optical network. GPON stands for Gigabit Ethernet passive optical network. GPON uses ATM for voice, Ethernet for data, and proprietary encapsulation for voice. It offers faster Gbps than EPON on downstream and upstream bandwidths. GPON provides a downlink rate of 2.5gbps. Unlike EPON, GPON is asymmetric, but it is a high-quality service designed for business use cases (QoS assurance and service access). GPON also uses access level protection mechanism (ALPM) and complete operation, management and management (OAM) functions.

EPON rivals GPON by using Ethernet packets instead of the ATM cells GPON uses. EPON is deployed as point-to-multipoint in fiber-to-the-premises (FTTP) networks or fiber-to-the-home (FTTH) networks. EPON uses a single optical fiber to serve multiple premises or users. EPON provides:
· Data rates of 1 Gbps upstream and downstream 
· Access to data like Internet, voice, and video service.

10G-PON
10Gbps passive optical network (10G-PON) is a next-generation solution following the current-generation gigabit passive optical network (GPON) (ITU-T G.984) and Ethernet passive optical network (EPON) (IEEE 802.3ah) solutions, basically offering higher bandwidth and additional features. Like its predecessors, 10G-PON will allow multiple users to share the capacity over a passive fiber-optic "tree" infrastructure, where the fibers to individual users branch out from a single fiber running to a network node. Both GPON and 10G-PON can provide services for up to 128 ONU. 10G-PON can provide services for 128 users for each PON, and use extenders/amplifiers to provide more services.