GPON vs EPON: rate, split and reach
GPON (ITU-T G.984) is 2.488 Gbit/s down and 1.244 Gbit/s up, split up to 1:128. EPON (IEEE 802.3ah) is a 1.25 GBd line over 10 or 20 km. No prices.
GPON, specified in ITU-T G.984, sends 2.48832 Gbit/s downstream and usually 1.24416 Gbit/s upstream, with a maximum split of 1:128. EPON, specified in IEEE 802.3ah, is a 1.25 GBd Ethernet line (1 Gbit/s at the MAC) over the 10 km PX10 or 20 km PX20 budgets. This page does not quote a product price. The passive outside plant is the same kind of plant for both.
GPON and EPON side by side
Figures below are the standards’ own values, not a catalogue. Where a standard does not set a number, the cell says so.
| GPON | EPON | |
|---|---|---|
| Standard | ITU-T G.984 (line rates in G.984.2, reach and split in G.984.1) | IEEE 802.3ah, 1000BASE-PX |
| Line rate | 2.48832 Gbit/s downstream. Upstream 1.24416 Gbit/s or 2.48832 Gbit/s | 1.25 GBd line rate. 1 Gbit/s at the MAC |
| Split ratio | Maximum 1:128, defined in G.984.1 | Not defined. The split has to fit the PX10 or PX20 power budget |
| Reach | Physical 20 km. Logical 60 km. Maximum differential fiber distance 20 km | PX10: 10 km. PX20: 20 km |
| Typical market | The ITU-T system an operator names when the OLT is a GPON OLT. No market share is published here | The IEEE system an operator names when the OLT is an Ethernet PON OLT. No market share is published here |
| ODN components | Feeder fiber, splitter, distribution fiber, drop, then a GPON OLT and ONU/ONT | The same passive parts: feeder, splitter, distribution, drop. The OLT and ONU follow IEEE 802.3ah |
Both standards use the 1490 nm downstream window and the 1310 nm upstream window. G.984.2 specifies downstream 1480–1500 nm and upstream 1260–1360 nm. IEEE 802.3ah uses the same two windows for 1000BASE-PX. Which fiber grade you pull for those windows is the subject of G.652.D vs G.657.
Faster successors exist and are not in the table. XGS-PON is ITU-T G.9807.1. 10G-EPON is IEEE 802.3av. Order against the standard your OLT vendor names, not against this page’s 1G/2.5G pair.
Which one a buyer should specify
The OLT is already chosen. Match the outside plant to that OLT. A GPON OLT needs GPON ONUs and a loss budget inside the optics class the vendor names (G.984.2 defines those classes). An EPON OLT needs EPON ONUs and a loss budget inside PX10 or PX20. The fiber, the splitter and the drop are the same kinds of parts either way. Name the optics class and the split ratio on the bill of materials so the loss can be checked.
The OLT is not chosen yet. The choice is the OLT vendor’s standard, not the cable. GPON carries more downstream bits per fiber (2.48832 Gbit/s against a 1.25 GBd EPON line) and G.984.1 allows a higher maximum split (1:128). EPON stays inside Ethernet framing. Pick the OLT first, then the split that fits its budget.
You supply fiber or cable. G.652.D and G.657 are specified the same way for both. Attenuation at 1310 nm and 1490 nm is what the loss budget uses. Optical fiber is the reel product. Send the fiber grade, the split ratio and the OLT optics class with the bill of materials.
Sources
- ITU-T, “G.984.1: Gigabit-capable passive optical networks (GPON): General characteristics”, including the 60 km logical reach, the 20 km physical reach and the 1:128 maximum split. itu.int
- ITU-T, “G.984.2: Gigabit-capable passive optical networks (G-PON): Physical media dependent (PMD) layer specification”, 2.48832 Gbit/s downstream and 1.24416 or 2.48832 Gbit/s upstream. itu.int
- IEEE 802.3ah-2004, later carried in IEEE 802.3, 1000BASE-PX (1.25 GBd, PX10 and PX20). The project page is the IEEE 802.3ah task force. ieee802.org
Next guide Fiber optic cable prices in 2026: what fiber, cable and FTTH parts cost from China