Number of ports occupied by the optical splitter

An optical splitter typically occupies one input port on the OLT and provides multiple output ports, commonly ranging from 2 to 64 outputs depending on the split ratio.

Understanding Split Ratios

The number of ports on an optical splitter is defined by its split ratio, expressed as 1:N, where N is the number of output ports connected to end-user devices (ONTs or ONUs) from a single OLT port . For example:

• A 1:32 splitter takes one input from the OLT and splits it into 32 outputs, serving 32 subscribers .
• A 1:64 splitter can serve up to 64 ONTs from a single OLT port, commonly used in EPON networks .
• GPON systems can theoretically support up to 1:128, though 1:64 is often preferred for practical bandwidth and service quality considerations .

Splitter Architectures

Optical splitters can be deployed in centralized or distributed/cascaded architectures:

• Centralized splitting: All splitter outputs are located at a central point, allowing flexible jumper connections and easy testing. A single OLT port connects directly to all splitter outputs .
• Cascaded/distributed splitting: Multiple splitters are used in stages to reach the desired total split ratio. For example, a 1×32 split can be achieved using a 1×4 splitter followed by four 1×8 splitters, still occupying only one OLT port but distributing fibers across multiple locations .

Practical Deployment

• In FTTH PON networks, a single OLT port connected through a splitter can serve 8, 16, 32, or 64 ONTs, depending on network design and bandwidth requirements .
• In Passive Optical LANs (POLs), splitters typically allow up to 32 devices per OLT port, with each ONT potentially supporting multiple Ethernet ports for local connectivity .
• The choice of split ratio balances cost efficiency, bandwidth allocation, and network scalability. Higher split ratios reduce hardware costs but may limit per-user bandwidth .

Summary

• Input port usage: 1 OLT port per splitter input.
• Output ports: Typically 2–64, depending on the split ratio and network design.
• Architectures: Centralized (all outputs at one location) or cascaded/distributed (multiple stages to reach total outputs).
• Practical limits: EPON up to 1:64, GPON up to 1:128 (commonly 1:64), POLs up to 32 devices per OLT port. By understanding the split ratio and architecture, network planners can efficiently determine how many ports an optical splitter occupies and how many end-user connections it can support.