ONU vs Router: Can ONUs Replace Routers？

In today's home and business networks, having a reliable and stable internet connection is essential. Both ONUs and routers are key devices for providing high-speed internet services. This often leads people to wonder: What's the difference between an ONU and a router? Can an ONU replace a router? In this article, we'll clearly explain the differences and discuss situations where an ONU can be used instead of a router.

ONU - Connect End-Users to the Passive Optical Network

The Optical Network Unit (ONU) is a crucial component in Passive Optical Networks (PON) and is widely used in Fiber-to-the-Home (FTTH) networks. Typically installed at the user's location, it connects end users to the PON. The main function of the ONU is to convert optical signals from the PON link into electrical signals that devices like routers or computers can use. It can also receive signals from customer devices and send them back to the Optical Line Terminal (OLT).

ONUs come in various types and configurations, such as Subscriber-Facing Units (SFU) and Home Gateway Units (HGU), etc.. Overall, ONUs play a vital role in deploying FTTH networks, providing high-speed broadband connections to homes and businesses.

Figure 1: ONU - Connect End-Users to the Passive Optical Network

Router - Connect and Manage Multiple Computer Networks

As is well known, most user-side routers can broadcast Wi-Fi. Specifically, a router is a device used to connect multiple computer networks and allow them to communicate with each other. It typically connects to a modem. Think of it as the brain of your home or business network, managing and directing traffic to ensure data packets are delivered smoothly and accurately.

Additionally, routers have Network Address Translation (NAT) capabilities, allowing them to convert private IP addresses to public IP addresses, thereby providing a secure network environment for users. Routers are not just for homes or offices. They’re also widely used in schools, businesses, data centers, and anywhere else that needs network connectivity, management, and control.

Figure 2: Router - Connect and Manage Multiple Computer Networks

ONU vs Router: Can ONUs Replace Routers？

In fact, some ONUs already support wireless Wi-Fi functionally. In this regard, ONUs and routers seem to have common features, which is why people often confuse the two. But can Wi-Fi ONUs fully replace routers? That depends on the ONU's performance and the users' actual internet needs.

ONU vs Router

In a network, Optical Network Units (ONU) and routers each play crucial roles. The primary function of an ONU is to achieve optical-to-electrical conversion, transforming fiber-optic signals into electrical signals for homes or businesses. Due to its core task of optical-to-electrical conversion, ONUs typically have fewer network ports, limiting the number of direct connections. However, with technological advancements, Wi-Fi-enabled ONUs have emerged that can meet the internet needs of small spaces with fewer devices, such as a studio apartment or a one-bedroom unit.

To build a more comprehensive and feature-rich network, ONUs are often used in conjunction with routers. Wireless routers provide stronger network signals and support more device connections. This combination ensures high-quality network access while accommodating multiple devices, enhancing overall network performance and user experience.

In summary, ONUs and routers each have their specific functions and advantages. Using both together when setting up a network can achieve optimal network performance and user experience.

HGU ONU: An Integrated Solution to Replace Routers

As GPON networks develop, operators are starting to provide voice, data, and cable TV services through fiber optics. This has also driven the functionality of ONUs to gradually evolve towards integration. The emergence of HGU ONUs may address the drawbacks mentioned above when using a wi-fi ONU as a router. This type of ONU is primarily intended for individual home users, featuring home gateway functions and supporting routing modes. It can handle broadband dialing on its own, allowing connected computers and mobile devices to access the internet directly without additional dialing. In other words, an HGU-type ONU can replace a router.

In FS solutions, there are scenarios where the HGU ONU directly replaces the router. As illustrated below, FS opted for the Wi-Fi 6 ONU for campus dormitories and apartment areas while constructing a full optical university network. Essentially, dormitories and apartments can be viewed as individual households. Here, the ONU substitutes the router, offering dual-band support (2.4GHz and 5GHz) and transmission speeds up to 3000Mbps. This setup allows students and staff to access the network continuously, even in high-density environments, reducing latency. In short, through the ONU, users in dorms and apartments can enjoy a seamless high-speed network experience.

Figure 3: Application of Replacing Router with Wi-Fi6 ONU

Conclusion

The functionality of ONUs has greatly expanded with the development of communication technology and market demand. The FS HGU ONU not only converts optical signals to electrical signals but also functions as a router. It offers stable and efficient Wi-Fi service to end users. If you are still confused about building a cost-effective PON network or choosing the right ONU, please feel free to contact us.