Asus RT-AC51U WiFi router: Pros and Cons
The Asus RT-AC51U (RT-AC51U) router released in 2014. It is powered by MediaTek MT7620A @ 580 MHz chipset, 64 MB of RAM and 16 MB of flash. The AC750 router is compatible with IEEE 802.11a/b/g/n/ac standards, and the maximum speed that you can get with RT-AC51U is 300 + 433 Mbps. The router has 1 x 10/100 Mbps WAN and 4 x 10/100 Mbps LAN ports.
The RT-AC51U is a good choice for users seeking a reliable and feature-rich router that supports the latest Wi-Fi 6 technology. The USB connectors on the RT-AC51U router add versatility to your network by enabling file sharing, media streaming, printer sharing, and other USB-enabled functionality. Asus has received recognition and awards for their networking products.
Asus RT-AC51U (RT-AC51U) pictures




The specifications below are based on the official data published by the manufacturer, but we also take user reviews into consideration. If you found an error or something lacking in the specifications above for the Asus RT-AC51U, then don’t hesite and signal the problem to us.
Asus RT-AC51U (RT-AC51U) specifications
Brand | Asus |
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Name | RT-AC51U |
Type | RT-AC51U |
Rating | |
Launch | 2014 |
Body
Dimensions | 189 x 129 x 36 mm |
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Weight | 270 g |
If you have limited space available for your router, such as in a small apartment or office, the dimensions can determine whether it can fit in the designated area or not. It's important to consider the physical size of the router, including its height, width, and depth, to ensure it can be accommodated in your space. If you purchase a router online or have it shipped, the weight may affect the overall cost. Heavier routers can result in higher shipping charges, especially for international deliveries.
System
Chipset | MediaTek MT7620A @ 580 MHz |
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RAM | 64 MB |
Flash | 16 MB |
OS | Asus |
Power supply | 12 V / 1 A |
The MediaTek MT7620A @ 580 MHz CPU, combined with other factors such as RAM capacity and firmware optimization, determines the overall performance and responsiveness of the router. The RT-AC51U has 64 MB of RAM. Some advanced router features and software functionalities require a certain amount of RAM to operate properly. For example, routers with more RAM can support advanced security features, VPN services, or QoS (Quality of Service) prioritization more effectively.
The RT-AC51U has 16 MB of flash memory. A larger flash memory allows for more storage space to accommodate future firmware upgrades. The process of upgrading the firmware on routers has become relatively simple and user-friendly over the years. The Asus provides easy-to-use interfaces and instructions to guide users through the firmware upgrade process. The Asus provides the appropriate power supply (12 V / 1 A) that matches the voltage requirements of the router. The power supply unit is designed to deliver the correct voltage to the router, ensuring its proper operation.
Network
Protocols | IPv4 IPv6 |
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LAN ports | 4 x 10/100 Mbps |
WAN ports | 1 x 10/100 Mbps |
Mobile network | yes, with USB dongle |
VPN support | PPTP L2TP OpenVPN |
The RT-AC51U router offers built-in security features to protect your network and connected devices. The majority of networking equipment, including routers, switches, and other network devices, is designed to support IPv4. The RT-AC51U router is also compatible with IPv6. IPv6 provides a significantly larger address space and offers various enhancements and improvements over IPv4. The RT-AC51U has 4 x 10/100 Mbps LAN and 1 x 10/100 Mbps WAN ports. The LAN ports of RT-AC51U router are numbered and are used to establish wired connections between the router and devices such as computers, gaming consoles, smart TVs, network-attached storage (NAS) devices, and other network-enabled devices.
WAN ports often require specific configuration settings based on the type of internet connection provided by your ISP. If you have a high-speed internet plan with speeds exceeding 100 Mbps, you may experience a bottleneck in wired connections due to the limitation of the Fast Ethernet ports on the RT-AC51U router. By connecting the 3G/4G USB dongle to the RT-AC51U router, you can share the internet connection with multiple devices on your local network. This allows multiple devices, such as computers, smartphones, or smart home devices, to access the internet simultaneously.
The RT-AC51U comes with built-in OpenVPN client. OpenVPN employs a certificate-based authentication system, which enhances security and provides a more robust method of identity verification compared to traditional username/password authentication. PPTP uses the Password Authentication Protocol (PAP) or Challenge Handshake Authentication Protocol (CHAP) for user authentication. However, the authentication process itself does not provide strong security guarantees.
Wireless
Antennas | 2 x 5 dBi RP-SMA |
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2.4 GHz | yes |
5 GHz | yes |
60 GHz | no |
Standards | IEEE 802.11a/b/g/n/ac |
Class | AC750 |
Speed | 300 + 433 Mbps |
Transmit power | 18.5 dBm |
Security | WEP WPA WPA2 WPS |
Guest network | yes |
This router has 2 x 5 dBi, RP-SMA antennas. Many modern routers feature multiple antennas and use Multiple-Input Multiple-Output (MIMO) technology. This technology enables simultaneous transmission and reception of multiple data streams, increasing overall throughput and improving the Wi-Fi performance. The RT-AC51U is compatible with 2.4 GHz Wi-Fi. Many IoT (Internet of Things) devices, smart home devices, and older Wi-Fi-enabled devices primarily operate on the 2.4 GHz band.
This router operates on both the 2.4GHz and 5GHz frequency bands, allowing you to connect devices to the most suitable band based on their capabilities and requirements. The RT-AC51U AC Wi-Fi router is backward compatible with older Wi-Fi devices that support 802.11a/b/g/n standards. The AC750 refers to the maximum combined data transfer rate supported by the router across all Wi-Fi bands. The RT-AC51U is capable of a maximum throughput speed of 300 + 433 Mbps. The real-world speed of a RT-AC51U router is typically lower than its theoretical maximum speed.
The maximum TX power of RT-AC51U router is 18.5 dBm. Adjusting the TX power of a router can be useful in situations where you want to optimize the Wi-Fi signal strength and coverage. The RT-AC51U router offers several security protocols: WEP, WPA, WPA2, WPS. The WEP (Wired Equivalent Privacy) was the first security protocol for Wi-Fi networks but is now considered weak and easily compromised. It uses a static encryption key and has known vulnerabilities, so it is no longer recommended for securing Wi-Fi networks.
The WPA2 (Wi-Fi Protected Access 2) was introduced as an improvement over WEP and provides stronger security. If WPA3 is not available, WPA2-Personal with AES encryption is still considered secure. The RT-AC51U router offers WPS. The WPS (Wi-Fi Protected Setup) provides a simplified and convenient method for connecting devices to a Wi-Fi network. Instead of manually entering the Wi-Fi network name (SSID) and password, users can use the WPS feature to establish a connection with the push of a button or by entering a PIN. Once the guest network is set up on your Asus RT-AC51U router, your guests can connect to it using the specified SSID and password. They will have internet access, while being separated from your private network.
Connectivity
USB ports | 1 x USB 2.0 |
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Print server | yes |
File server | yes |
USB ports can offer additional functionality depending on the router's capabilities. The USB 2 port has a maximum theoretical data transfer rate of 480 megabits per second (Mbps), which is equivalent to 60 megabytes per second (MB/s). The RT-AC51U router has print server functionality. With a USB print server, you can manage printer settings, monitor print queues, and control access to the printer from a centralized interface. This can simplify printer management and administration tasks. The RT-AC51U router allows you to schedule automated backups of your important data to the connected USB storage device.
Administration
Default IP | 192.168.1.1 |
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Default username | admin |
Default password | admin |
The Asus router setup panel is accessed through a web browser. Connect your computer to the RT-AC51U router via Wi-Fi or Ethernet cable. In the address bar of the web browser, type in the 192.168.1.1 IP address. If you are unable to log in to the setup panel of your Asus router, performing a reset can be a helpful troubleshooting step. It is highly recommended to change the default password of your RT-AC51U router after the initial setup. If you forget the new password in the future, you may need to perform a factory reset on the router to revert to the default settings.
Asus RT-AC51U (RT-AC51U) comparisons
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