Preface
After spending a week researching routers, I realized that the time invested would be wasted if not documented, hence this article.
I previously wrote about ](/tech/my-home-network-2022.html), where I used a ZTE WiFi6 dual-band router provided by China Unicom. To be honest, the speed was decent—wired connections could reach around 500Mbps, but the wireless performance was lacking. Placing the router in the living room meant the bedroom signal was weak, and the bathroom had no signal at all. My wife often complained about Taobao and Douyin suddenly failing to load (connection drops?). So, I decided to take advantage of the Double 11 sales to consider buying a new router.
My Requirements
With the intention set, the first step was to clarify my needs. Here’s what the new router must meet:
- Strong signal. This is the primary reason for replacing the current router.
- Five Gigabit+ Ethernet ports. Devices like my Mac, PS, and Switch require wired connections for optimal speed, plus the R4S soft router—that’s four ports already. A fifth port is needed to connect to the optical modem.
- Stability (low tinkerability). Since I already have the R4S soft router, additional features like built-in UU accelerator or OpenWrt compatibility are unnecessary. High tinkerability often means higher prices and, worse, instability.
- WiFi 6. It’s the future—no further explanation needed.
- Budget under 500 RMB.
Technical Research
With these requirements in mind, I began researching routers.
Although I work in tech, I’m not well-versed in networking hardware. To keep things simple, I noticed a colleague bought an AX3000, so I considered getting a Xiaomi router too. After browsing JD.com’s marketing materials, forums, and encyclopedias, I picked up some basic concepts, explained here in plain terms:
- AX NNNN: The “NNNN” represents the wireless speed rating. Searching for AX3000, AX5400, or AX6000 will yield various brands—these aren’t specific models but indicate speed tiers. Higher numbers mean higher prices. “AX” refers to routers using IEEE 802.11AX technology (WiFi 6), while “AC” denotes IEEE 802.11AC (WiFi 5).
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Mesh Networking: Essentially, seamless roaming for large homes. If your place is big (say, 100+ sqm), one router might not cover everything. Traditional setups require disconnecting and reconnecting when switching routers, but mesh networks solve this by linking multiple routers to share data and provide uninterrupted coverage.
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2.5G/1G Ports: “1G” means 1 Gigabit, the maximum bandwidth the port can handle. Most home internet plans are under 500–1000Mbps, so 10G ports are overkill unless you have a NAS for local media storage.
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Link Aggregation: For WAN ports, it means combining two internet lines (e.g., two 500Mbps connections) for faster speeds. LAN port aggregation works similarly, but I didn’t explore this since I don’t need it.
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Dual-Band: Both 2.4GHz and 5GHz frequencies are available. Why keep 2.4GHz? Some older devices and smart home gadgets only support 2.4GHz.
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160MHz Channel Width: A WiFi 6 feature for faster speeds (previous standards maxed out at 80MHz). My ZTE router’s 5GHz band only supports 80MHz—bigger is better here.
- 4K QAM: Supposedly boosts download speeds, but currently, only Xiaomi phones see a 20% improvement; other devices don’t support it.
- OFDMA and MU-MIMO: These reduce latency for multi-device gaming, though oddly, TP-Link keeps them disabled by default.
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Multi-Core: More cores mean better performance (duh), especially for encryption/decryption. According to experts, Qualcomm’s chipset solutions are mature, while Broadcom and MediaTek’s are subpar.
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Signal Amplifiers: Self-explanatory—they boost signal strength.
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1GB RAM: More RAM allows for tinkering (e.g., flashing OpenWrt). Some routers, like the XDR5480, only have 16MB RAM, making them inflexible.
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USB 3.0 Port: For connecting external drives and enabling home file sharing.
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Built-in Game Accelerator: Usually a partnership with NetEase UU, providing VPN-like acceleration for Switch or PS5 online gaming, eliminating the need for a separate soft router setup.
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Active Cooling: Uses a fan. Passive cooling relies on ambient airflow—basically leaving it to fate.
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IPv6: Basically useless. Even if your router supports it, it’s recommended to disable it. A technology that hasn’t been widely adopted might as well not exist.
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Backhaul: Divided into wired backhaul and wireless backhaul, used for mesh networking. It’s said to improve transmission efficiency and stability, but I don’t fully understand it.
- Multi-band merging: Combines 2.4G and 5G into a single network signal. When a device connects, it first checks if it supports 5G; if not, it falls back to 2.4G. After researching, most people advise against enabling this feature because some smart home devices may stop working if it’s turned on.
Technical Selection
Alright, the above points are some of the marketing claims made by router manufacturers. For me, the actual purchase decision was based on my needs. After comparing various routers, I ended up buying the TP-Link XDR5480. Here’s why:
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Initially, I wanted to buy a Xiaomi router. After some research, I found that Xiaomi offers the best hardware for the price or the lowest price for the same hardware across all its products. However, I ultimately decided against it for the following reasons:
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Sneaky tactics: The older model, AX3600, was discontinued and replaced with an “upgraded” AX6000 version. But teardowns revealed that the new model actually used inferior components compared to the AX3600.
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Only four LAN ports, and they’re shared as a single gigabit connection—ridiculous. Combined with Xiaomi’s other product quirks, I gave up on the spot.
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Due to its high sales volume, I saw many complaints online about connection drops. A colleague who owns the AX3000 also reported this issue, though he wasn’t sure if it was his home network or the router. Adhering to the principle of “better safe than sorry,” I decided not to buy it!
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Next, I asked a colleague, who uses the legendary ASUS AC86U—a standout in the WiFi 5 era with a solid reputation. ASUS is a professional router manufacturer, unlike some brands that rely on OEMs. Additionally, ASUS typically produces high-end routers (priced in the thousands), which gives them a premium image. Their routers are also highly customizable, supporting firmware like Merlin and OpenWRT, earning praise from tech enthusiasts. However, I ultimately didn’t buy it because:
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Expensive.
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Too customizable. I don’t need that level of customization, and the added cost for features I wouldn’t use became a dealbreaker.
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Later, while browsing forums like V2EX and acwifi, I noticed many people recommending the XDR5480. After some research, I decided to order it for the following reasons:
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I searched extensively and found very few complaints about it.
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TP-Link is an established brand, previously known for budget products. The 5480 seems to be their attempt at a comeback, as it packs a CPU usually found in routers priced over a thousand yuan. It offers strong performance and exceptional 5G signal strength.
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Low customizability means stability—exactly what I need.
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Besides four gigabit LAN ports, it includes an SFP interface for direct fiber connection (using a transceiver) or as a 2.5G Ethernet port.
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Priced under 500, it fits my budget.
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The LAN port can be used for IPTV, meaning you could ditch the ISP’s modem (though I didn’t do this).
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Buy!
Continued Tinkering
After the router arrived, I checked its interface and found there wasn’t much to tweak. But with such a powerful router, it felt like a waste not to explore further, so I started experimenting.
My current network setup is as follows: Fiber enters the house and connects to the ISP’s modem (primary router). From there, it connects to the TP-Link router (secondary router), and all home devices connect to the TP-Link via wired or wireless connections. I’ve kept the modem’s WiFi enabled for troubleshooting—if the network fails, I can connect to the modem’s WiFi to determine whether the issue lies with the router or the modem.
Additionally, since I don’t need router-level VPN access, I connected the modem’s second gigabit port (the first is used for the secondary router) to my Sony TV. I installed the Android TV version of Clash to watch YouTube, which turned out to be a smart move—it ensures the TV remains usable even when I’m fiddling with the router.
Modem-Router Connection Methods
Terminology Explained
NAT (Network Address Translation)
Why can’t devices connect directly to the public internet? Why is NAT necessary? Simply put, it exists because IPv4 addresses are limited. ISPs don’t assign a unique IPv4 address to every household, so your home network is essentially part of the ISP’s larger private network. When your device sends a request, it goes through the router to the modem, where it undergoes NAT translation. Then, from the modem to the ISP’s servers, another layer of NAT translation occurs. However, the translation between the router and modem is often unnecessary, as explained below.
Subnet
In IPv4, the address is divided into four segments (hence “v4”). If the second-to-last segment differs, it’s a different subnet. For example, 192.168.1.1 and 192.168.0.1 are different subnets because their second-to-last segments are 1 and 2, respectively. Devices on different subnets can’t directly communicate.
DHCP (Dynamic Host Configuration Protocol)
This service dynamically assigns IP addresses. Only one DHCP server should exist per subnet; otherwise, conflicts may prevent devices from connecting to the internet.
Optical Modem Router - Router Routing
This is the standard default mode where the fiber optic cable connects to the optical modem, and a cable from the modem’s LAN port plugs into the router’s WLAN port, creating a primary-secondary router setup.
Advantages:
- Simple, requires no configuration.
Disadvantages:
- Devices undergo two levels of NAT address translation to reach the public network, causing unnecessary latency.
Optical Modem Router - Router AP Mode
This treats the router as a signal amplifier for the optical modem, allowing multiple networks to connect and enabling pairwise connections.
Advantages:
- Simple, only requires minimal setup.
Disadvantages:
- The optical modem bears a heavy load, handling dial-up, DHCP, NAT, etc., wasting the router’s performance.
Optical Modem Router - Router Bridge Mode
Similar to AP mode, it amplifies the optical modem’s signal and connects multiple networks but does not support pairwise connections. Pros and cons are the same as above.
Optical Modem Bridge - Router Dial-Up
Here, the optical modem only serves as a device to convert optical signals to electrical signals after fiber entry, with all other tasks delegated to the more powerful router. This is the setup I currently use.
Advantages:
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The low-performance optical modem only handles optical-electrical conversion (like the SFP optical stick mentioned earlier), with no other functions.
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The home network operates on a single subnet, making management easier.
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By requesting a public IP and configuring port mapping on the router (a common feature), it’s convenient to manage LAN devices and soft router applications remotely.
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Only one level of NAT address translation occurs at the router, reducing latency and maximizing bandwidth.
Disadvantages:
- Slightly cumbersome, as it requires contacting the ISP to modify the optical modem’s settings. If you change it yourself as some online guides suggest, the ISP may automatically revert the configuration, requiring some networking knowledge.
Router Direct Fiber Connection
This requires the aforementioned SFP optical stick. The stick plugs directly into the router’s SFP port, allowing the router to handle both optical-electrical conversion and dial-up. However, it’s said that the SFP module can get very hot, and consolidating all risks onto one device is impractical, so I didn’t opt for this approach—because it’s possible but unnecessary. Also, note that the XDR 5480 reportedly only works with TP-Link’s own optical stick; third-party sticks like Huawei’s may not be compatible (unverified). Optical sticks come in 2.5G and 10G (10 Gigabit) variants, with higher speeds being more expensive.
How to Set Up Router Dial-Up?
Location: Beijing Unicom. I searched many outdated posts online where users could ask Unicom technicians for the optical modem’s super password to switch from routing mode to bridge mode.
Some regions stubbornly refuse to allow optical modem bridging.
But it’s 2022 now, so I called Unicom. Here’s the conversation:
Me: Hello, I need a public IP for my home broadband.
Customer Service: Okay, please hold while I transfer you to a technical expert.
Technical Expert: You’re requesting a public IP?
Me: Yes.
Technical Expert: Alright, I’ll make the change on our end. Restart your optical modem in ten minutes, and it’ll be done.
Me: Great, thanks.
Done.
After getting the public IP, I still needed to switch the optical modem to bridge mode (forgot to mention it earlier), so I called again:
Me: Hello, I’d like to set up my optical modem in bridge mode. How should I proceed?
Customer Service: I’ll schedule a technician to visit tomorrow before 8:30 AM.
Me: Can’t you just make the changes remotely, and I’ll configure it here? Does a technician really need to come?
Customer Service: Yes.
Me: Okay.
The next day, the technician called:
Technician: You want to switch to bridge mode, right?
Me: Yes, I need remote access to LAN devices and services.
Technician: Got it. Wait a moment—I’ll have the backend make the changes, and the configuration will update automatically in five minutes.
Me: You don’t need to come over?
Technician: No need. If you’re setting up bridge mode, you must know what you’re doing. Just handle it yourself.
Me: I understand, but don’t you need to adjust settings on the optical modem?
Technician: No, the backend will push the configuration. The modem doesn’t even need a restart. Just enter the broadband username and password from the modem into your router. I’ll let you know once the changes are done.
Me: Alright.
Two minutes later, the technician confirmed it was ready. I simply selected “Dial-Up” in the TP-Link router’s internet settings and entered the broadband credentials. If you don’t know the username/password, ask your Unicom technician or check the optical modem’s interface. Although the password is encrypted, you can use F12 to modify the input element’s type—no big deal.
Simple TP-Link Tricks
DDNS + port mapping is the only notable feature, but it’s sufficient for my needs. With my R4S, I can remotely access its interface and services via port mapping and TP-Link’s built-in DDNS. Here’s how to set it up.
DDNS
Schematic diagram:
You have a public IP address, but your ISP assigns a dynamic IP to your home broadband, meaning the address changes frequently. Checking the IP every time you want to access it is tedious. How can you access it conveniently? The answer is DDNS (Dynamic Domain Name System). Your router always knows your public IP address, and by configuring DDNS on the router, you can bind a domain name to this address. Whenever you access that domain, it will resolve to the latest public IP of your home broadband.
References:
Virtual Port Mapping
Diagram:
For security reasons, ISPs typically block common web service ports like 80 and 8080 on your public IP. Additionally, multiple services may run on different ports within your local network. Therefore, you need port mapping—redirecting traffic from an external port to an internal port. Here’s how to set it up:
References:
Result:
Practical Applications
Currently, I use this setup for:
- qBittorrent downloads
- FileBrowser for file management
- Aria2 for downloads
I haven’t exposed ports for Aliyun Drive since I only need it within the local network:
Aria2 is great for general downloads, replacing Chrome’s default downloader. Its multi-threading capability makes downloads significantly faster. Here’s a comparison for the same resource:
A common use case: When my wife asks me to download something, I share it with her via FileBrowser, which even allows setting expiration dates for shared links—super convenient:
Closing Thoughts
Network topology is fascinating. In the early days of the internet, no one could have predicted its current scale. Every system evolves from simplicity to complexity, from primitive to advanced. By studying simple devices, you can uncover how early designers thought about the internet, the problems they faced (like IPv4 exhaustion and the NAT workaround), and how they solved them. It’s intriguing to ponder: How would you have tackled these challenges?
From the author:
I often wish that when facing some key decisions in life, someone could tell me the best course of action so that I would not waste my precious time. Putting myself in others' shoes, I therefore write blogs often, hoping to record in this tiny corner of the vast Internet the once-in-a-lifetime experiences that matter to me, and to help those who seek help.
