How to classify FTTX Topology

FTTX technology is referred to access network technology which generally divided into point-to-point (P2P) and point-to-multipoint (P2MP) two kinds of access methods,.  A passive optical network (PON) is a point-to-multipoint network architecture

FTTX can be FTTH (fiber to the home), FTTE (Fiber to the telecom enclosure), FTTC (Fiber to the curb), the FTTB / O (optical fiber to the building / office) and so on.

FTTX Topology Classification

P2P (point-to-point)

The point-to-point (P2P) architecture has a core switch at the central office, which connects over optical fiber cables to an aggregation switch at the distribution points. These locations are typically your street corners, etc. The aggregation switches have many fiber ports and each port will directly connect to an ONT (Optical Network Termination) placed at the residential localities using fiber cables.

P2M (point-to-multi-point):

The point-to-multi-point (P2M)/ passive optical network (PON) architecture is the same, except in the distribution points. Instead of the active switches with fiber ports, passive splitters are used. These splitters do not require any power supply and they can divide an optical signal into 32, 64 or even 128 shared connections. The same signal is transmitted to all the houses beyond the splitter, but each ONT in each house knows how to decipher the information meant only for itself. Of course, the ONTs used in P2P are different from the ones used in P2M. Also, the total bandwidth is shared between all these shared connections.

Comparison of both topologies

	Ethernet	PON
Scalability	100 Mbit/s to 10 Gbit/s	2.5 to 10Gbit/s
Bitrate sharing	Dedicated bitrate	shared bitrate
Security	High through dedicated medium	Requires encryption, vulnerable to DoS attacks
Upstream traffic management	Highly sophisticated through switch matrix	Limited by capabilities of MAC protocol
Interoperability OLT-CPE	Easy because of ubiquitous technology	Still challenging
Per-subscriber CO power consumption	We defined low value (≈2W), independent of take rate	Depends on take rate - from very high to very low
≈1150 homes connected per pack	Depends on take rate - from very high to very low

How can you determine the best topology?

You need to understand your options for your deployment of fiber in a variety of topologies.

• Which business designenterprize model are you planning to apply today?
• Which business designenterprize model are you planning to apply in Two decades from now?
• Are limitations for your deployment of certain topologies with different serious research into the existing infrastructure (e.g., ductwork), or conservative presumptions?

Just in case your access infrastructure must be flexible, business designenterprize model and technology-agnostic, then deploy a place-to-point fiber.

How will you determine the very best access technology?

• Understand your choices for the technologies to be used inside the fiber topology.
• Which peak bitrates will clientsyour site site visitors require inside the time period of we've got we have got we've got the technology (e.g., 5 years) that you just deploy today?
• Do you want to differentiate technologies between low-tier and-tier residentials, SMEs, companies?
• Can be a unified approach simpler and cheaper ultimatelyultimately?
• Would you like an Radiation video overlay?

Just in case your technology choice should be equally suitable for an array of clients, be highly scalable, mature, secure, then deploy Ethernet.


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