What does it mean when a router is used as a bypass router? Don't just use old routers to advertise nearby; my first time taking it crashed FamilyMart

TV startup ads last about ten seconds, and as soon as I cast to my phone, the store pops up. I endured for more than half a year, rummaged through my drawer, found a dusty N1 box, and found it a new job—as a bypass router. The name sounds mysterious, but it's actually just a network cable. But the first time I connected it, I crashed my FamilyMart network for two hours. This article will thoroughly explain the principles, connection methods, and the pitfalls I've encountered.

to be straightforward: a bypass router is not a router replacement, it's hiring an external

My main router is the Xiaomi AX3000T, so I dial and send WiFi as usual, nothing I don't need to change . For a bypass router, find another device—an old router, N1 box, or Wankeyun—and plug a network cable into the main router's LAN port and hang it into the local area network. It doesn't dial-up or send WiFi, but does the dirty work that the main router can't or doesn't want it to do: removing ads, filtering web pages, and giving special care to individual devices.

key is that "whoever needs it goes to find it." If the TV wants to remove ads, just point the gateway to it in the TV settings; If you don't want to mess with your phone, just keep using the main router, and you can't sense any bypass routers at all. This is a completely different matter from replacing routers or forming Mesh—Mesh supplements the signal for the whole home, while bypass routing adds services to individual devices.

previously wrote about soft routers, mentioned the phrase: "Try out the water with a bypass router first, don't rush to unplug your old router." That's exactly what it meant, but the main topic in that article was whether to buy a soft router or not, and didn't go into the connection method. This article specifically adds: how exactly do you take it and where the traps lie.

traffic: Why is it called a single arm, and what is the plot for this route

usual traffic has two hops: the phone sends a request, goes to the main router, and goes straight out of the network. After using a bypass router (using TV as an example), traffic jumps three times: the TV request goes to the bypass router first, the ad domain is blocked halfway, and the rest is handed over to the main router to exit the network.

side router has only one cable connected to the local area network, and both entry and exit use the same 'arm,' hence the term single-arm router . What it calls doesn't matter; what matters is that you think about one thing: if you bypass this lane, the speed ceiling will shift from the main route to a bypass route.

the numbers I tested: the N1 box uses a 100Mbps Ethernet port, and after the TV bypasses it, the speed peaks at 93Mbps. It's more than enough for video play—4K is only 25Mbps—but if you want to download large files with it, don't count on it. My home has 500M broadband, and the main router direct connection can run over 480MB. This is the difference between "device-level" and "global" bandwidth, which will be explained later.

four steps of the connection, I made a mistake the first time at the third step

Step one: Plug the network cable into the nearby router's LAN port—never plug it into WAN. plugged into a WAN, it becomes a secondary router—it's a whole different thing. The device you connected to and other devices at home can't find each other, and NAS and screen casting are completely lost.

Step two: fix the IP address of the bypass router. the bypass router's own backend (N1 flashed OpenWrt to default to 192.168.1.1, so connect to it separately first), manually set the IP to the main router in the same subnet, for example, the main router is 192.168.31.1, and the bypass router is set to 192.168.31.20. Use this account later, and record it in your phone's notes.

Step 3: Turn off the DHCP on the bypass route. this is the most classic pitfall online: DHCP is a service that "sends IP addresses to devices." The main router sends addresses, and the side router sends as well. Two machines compete to send addresses, and the device gets the address based on who's the quickest user. The first time, I forgot this step.

step four, decide who will go to find it. two ways to play:

• device level (recommended): Only on the device where you want to advertise, manually change the gateway and DNS in WiFi settings to 192.168.31.20; do not touch any other devices. TVs and elderly phones are commonly used here.
• Global: Enter the main router backend, change the DHCP-issued gateway to 192.168.31.20, and the whole family data will automatically bypass the router. It saves a Taiwan Reform machine, but the risks are high, which will be discussed in the next section.

the four pitfalls I stepped on, sorted by the degree of pain

pitfall one: Double DHCP, the whole family is inconsistent. the afternoon after the connection, the WiFi at home intermittently worked, the web couldn't be opened, WeChat messages could be sent, and web pages wouldn't open. I searched for two hours and finally saw both devices labeled as "DHCP servers" in the main router's device list, which made me realize what was happening. Remember this symptom: device can be used sometimes but not for a while. Chances are, dual DHCP is fighting . Just turn off DHCP in the background via a side router.

Plot 2: 100Mbps ports as the whole system, 500M broadband becomes 93M. a while, I wanted the whole family to advertise and point the DHCP gateway for the main router to N1, but the whole house speed test dropped to 93 Mbps—100 Mbps is the ceiling, regardless of how strong the main router is. For broadband above 300M, 100Mbps devices are only capable of handling equipment-level tasks. If you want a global setup, at least find a gigabit device, or use the same setup as N1 or Wankeyun boxes first confirm the network port specs.

Plot 3: In global mode, the bypass restarts by 1, and the whole family is disconnected. once I restarted the N1, my wife saw the TV screen going black halfway and looked up at me. Since then, I switched back to the device level, only running the TV and my own phone—bypassing is whatever it wants, with at most two devices affected. Global mode essentially turns the bypass router into a single point of failure for the whole family. If someone at home "only uses the internet and doesn't mess around," be cautious.

pitfall four: just changing the gateway without changing the DNS doesn't work at all. Ad-removal services like AdGuard Home rely on DNS queries to block ad domains. I pointed to the TV gateway, and the DNS still had the main router set in, but not a single ad was missing. The gateway and DNS need to be together changed to 192.168.31.20; missing either is useless.

Who is worth hanging, and who should you not mess with

After more than half a year of

fiddling, I've distilled my advice for friends into this chart:

there's another intermediate state: if the old router is too old and its performance is so weak that even using ad plugins lags, it fails as a bypass router. But it has other uses—WiFi5 old router, you can replace the AP with a patch the network port, or replace the poor signal with a wireless repeater to patch the corner signal . These are all ways to keep the old device shining.

Conclusion: The Order of Action and a Life-Saving Phrase

follow this order for the lowest chance of failure: first flash the system on the device (follow the steps for flashing OpenWrt on N1 follow the flashing ), then plug it into the LAN, fix the IP, turn off DHCP, and test the TV for a week of device-level testing for a week . Once it's stable and you've figured it out, decide whether to open it up globally.

life-saving rule: if the bypass fails at any time, change the device's gateway and DNS back to "Auto Acquisition," or simply unplug the cable, and the whole family will immediately return to normal. They are non-staff personnel, and the biggest advantage of being non-staff is that they can be dismissed at any time without having to pay compensation.