• Posted on Mar 29, 2023

Few things are as crucial to 21st-century living as the Internet. Almost all Americans use the Internet for entertainment, business, and education. Simply put, life as we know it wouldn’t exist without the Internet.

That’s why understanding how the Internet works is as important as ever. Modern Internet architecture relies on passive optical networks (PONs). Knowing the difference between EPON and GPON optical fiber networks can help you decide which option is best for your Internet needs.

What is EPON?

EPONs, or Ethernet passive optical networks, rely on Ethernet technology to provide Internet access. They use Ethernet packets in a point-to-multipoint configuration within a network. EPON are either fiber-to-the-home (FTTH) or fiber-to-the-premises (FTTP) networks.

The IEEE established EPON as a standard in 2004. It enjoys widespread popularity in East Asian countries such as Japan, China, Korea, Taiwan, and much of Europe. Users rave about its efficient Internet, video, and voice services. It also provides up to 1 Gbps of data access and download speeds.

What is GPON?

GPON refers to gigabit Ethernet passive optical networks. Unlike EPONs, GPONs rely on several different packets for data access. They use Ethernet for data and ATM technology for voice calls. However, GPON still provides consistent and reliable Ethernet access to its users, providing a full range of operations, administration, and management (OAM) functions.

GPON uses optical splitter technology known as optical wavelength division multiplexing to use a single fiber for upstream and downstream data. While GPON units provide 2.5 Gbps of data access, individual users only get a fraction of this speed, depending on how their ISP allocates it. GPON networks are most popular in the United States, and they lack the international appeal of EPON systems.

EPON vs. GPON – Explained

Both GPON and EPON systems provide customers with unique benefits. However, each technology has its fierce defenders, leaving many consumers confused as to which network works best for their needs. Here are some of the differences between EPON and GPON networks.


Reach refers to the number of optical network units (ONUs) a network can service. Both EPON and GPON have an effective range of 20 kilometers. However, both units vary in reach, as a single optical line terminal (OLT) can only support so many ONUs.

EPON OLT reach has no innate limit, so the practical limit depends on the type of optics used. EPON tends to support either 32 or 64 ONUs per OLT. GPON, on the other hand, can support up to 128 ONUs. This variation in ONU support is a key difference between EPON and GPON optical fiber networks.

Bandwidth and Speed

GPON offers 1.25 to 2.5 Gbps for downstream services, while its upstream bandwidths scale from 155 Mbps to 2.5 Gbps. EPON, on the other hand, offers a flat bandwidth of 1 Gbps. It’s worth noting that EPON’s bandwidth is technically 1.25 Gbps; it’s just that 25 percent of this bandwidth goes towards encoding data.

While GPON doesn’t require 25 percent of its bandwidth for encoding purposes, it does require special switches to reach its full speed of 2.5 Gbps. These switches are often pricy to obtain, qualifying the edge GPON otherwise has in this particular domain.


The difference between EPON and GPON optical fiber networks concerning cost is astounding. EPON equipment costs around 10 percent of the price of comparable GPON gear. Moreover, GPON’s ATM framework is complicated and expensive compared to EPON’s straightforward Ethernet maximalism.

On the subscriber side, GPON systems cost more than their EPON counterparts. Potential customers should consider this fact when evaluating the difference between EPON and GPON optical fiber networks.


EPON’s Ethernet packets carry up to 1518 bytes of data in a variable-length form. This adaptability allows for easy data transfer. GPON, on the other hand, uses fixed-length, 53-byte cells to transfer data.

GPON’s use of fixed-length cells makes it more difficult for GPONs to transfer IP-formatted traffic. In order to comply with these formatting restrictions, the system has to break down GPON packets into 48-byte segments, each containing a 5-byte header piece. This process uses time and resources, wasting 5 bytes per each transferral process.

EPON networks shine in efficiency, as they easily adapt to IP-specific regulations. Moreover, Ethernet packets have a higher data-to-overhead ratio than GPON’s ATM protocol. To function at a comparable level, GPONs require higher-grade optics, increasing overall unit cost. However, GPON’s purpose-built function as a point-to-multipoint protocol does mean that it requires less Ethernet usage than EPON.


Both GPON and EPON offer encryption as a standard protocol. However, EPON encryption covers downstream and upstream data transfer, while GPON encryption only covers the downstream transfer process. Both networks include support for OAM services and carrier-specific and vendor-specific services.

Design Architecture

Regarding design architecture, the difference between EPON and GPON optical fiber networks is stark. As mentioned, GPON uses three networks: Ethernet for Data, ATM for voice, and proprietary encapsulation for voice. EPON uses Ethernet as a single network to fulfill all three functions.

GPON’s architecture relies on a multiprotocol transport solution. Its virtual circuits vary by location and the service involved. While this tailored approach makes for quality service, it also costs significant overhead. Moreover, GPON networks require several other conversions, such as a point-to-point protocol (PPP) and virtual channel (VC) termination.

EPON’s design is more streamlined, as its sole reliance on Ethernet means fewer conversions are needed. As a result, it provides more seamless and cost-effective service for customers. Ultimately, this difference between EPON and GPON optical fiber networks comes down to mere user preference.

Professional Network Solutions

Are you still curious about the difference between EPON and GPON optical fiber networks? eNetwork Supply has you covered! We provide clients in the data, IT, and telecommunication industries with efficient, premium-grade network hardware supplies. So whether you’re interested in new routers, cables, or servers, we’ve got something that fits your needs. Call us at (312) 283-5983 to speak with one of our team members today.