After the fourth year of using Optical Mode, the network became more and more laggy. I blamed it on the router and wronged it.

Our home broadband was installed in 2022, Telecom is 300M, and the optical modem has been squatting in the weak current box without anyone taking care of it. As autumn begins this year, something is obviously wrong with my home network.: After nine o'clock in the evening, video calls become blurry, the TV box changes channels in circles, and the FamilyMart website freezes when I try to download it in my study. I changed to a new router first, it didn’t work ； I was thinking about upgrading to Gigabit, but was stopped by my colleagues. After digging all the way to the bottom, the cat in the pot is optical modem - a four-year-old cat. The equipment is indeed not broken, but its small body can no longer carry more than 30 pieces of equipment in our home. This article writes down the troubleshooting process and solutions in order. Regarding the matter of the optical modem becoming stuck, I was The cat is tired I have written about one level from the perspective of CPU and memory usage. This article is about another level.: How to look at the number of connections, how to say new words, and how to choose a new bridge, you can read the two articles together to get a more comprehensive view.

Eliminate the router first, don’t follow my example and spend 400 yuan in vain

When the network is stuck, the first reaction of 80% of people is that the router is not working, and I am the same. The old one was a Mercury, and it was indeed four years old. I directly ordered a new one, which cost more than 400 yuan. The night I installed it, the card was still the same. Only then did I calm down and do the elimination method.: New router + new network cable + laptop plugged directly into the LAN port of the router to measure the speed. It came out at 296M, which is full speed. There is no problem from the router to the device.

Then there are only two paragraphs left in the question.: Either on the line from the optical modem to the router, or on the optical modem itself. I also changed the cable that came out of the optical modem to a Category 6 cable, and there was no change. There is only one suspect left. The complete number of channels to be determined (WAN port, LAN port, negotiated speed, etc.) has been written before in the article about WiFi being full but no network. I will not repeat it here. I will only talk about the conclusion.: After the router was eliminated, the finger pointed at the optical modem. .

Check the number of connections in the background. This is a key step.

You can enter the optical modem backend with a normal user account by typing in the browser address bar. 192.168.1.1 , the account password is on the sticker on the phone (if it has not been changed). After entering, look for the "Status" or "WAN Information" page. Each menu is different, but they all have similar things.: Current number of connections , some are called "number of NAT sessions" and "active sessions", which have the same meaning. The number of ways to judge whether a cat is tired depends on the CPU and memory usage. The article 1493 is more detailed. In this article, the number of connections is enough to determine whether the cat is tired.

During the evening rush hour at our house, the number is always 2,788, and the number of smart devices in our house is only about 30. What is the concept of this number? A Laoguangmao from five or six years ago is usually rated to be able to handle several thousand concurrent sessions when shipped from the factory. Note that it is "factory". After four years of running, more and more memory fragments and connection residues are accumulated in the firmware, and the actual amount that can be stably processed is decreasing. When no one is around during the day, if you look at it and the number of connections drops back to more than 300, the network will be normal - lagging and the number of connections rise and fall at the same time. This correspondence is the strongest evidence.

Why does my family have so many conversations? Smart homes are noisy. Three cameras, two speakers, a sweeper, a clothes drying rack, a dozen lights, plus mobile phone, computer and TV boxes are all crowded into the same exit. I'm here for this The whole family home WiFi card article Calculate the account: The equipment storm first crowded out WiFi, and after that, everyone flocked to the main exit of optical modem. You can easily exchange a router for 1,800 yuan, and the optical modem is an entry-level product provided by the operator. Cheap chips, small memory, and part-time job as a router , the two sides are not of the same magnitude at all.

Three signs that a optical modem is old

In addition to the number of connections, the optical modem is "old" and has several accompanying signals. I checked them one by one on my own unit.:

The first one needs to be said in a separate sentence. Optical modem and router "restart is useful" are not the same thing: Restarting the router clears the connection table in memory. This is common to all manufacturers. ； Frequent power outages in the optical modem will damage the optical path. The light decay of my mother's machine increased from -24 to -26.4. The constant on and off of the power supply accelerates the aging of the laser. I am confused by this. The article about regular power outages of optical modem I paid my tuition fees. Therefore, if the cat is stuck, you can restart it for emergency relief, but don't set it to "maintenance" where the power is cut off every day, as that is counterproductive. Whether the equipment can still hold up or not? Light failure is another question. It depends. The article about optical modem lifespan , anything within minus 24 is considered healthy.

Solution 1: Call 10000 to report a fault and get a replacement at zero cost.

After confirming that it was optical modem's fault, the easiest way is to report the problem. The optical modem is an asset of the operator. If it is broken or aged, if you call 10000 and report that "the Internet is slow and the optical modem is running unstable," the technician will come and replace it for free. Usually, the modem will be refurbished or a new model, and the chip and memory are better than the generation four years ago. I made a call, and the technician came to my door the next day and replaced it with one starting with TEWA (the specific model is different in each province). After the replacement, the network connection number was 2,800, and the network was no longer stuck. There is zero cost before and after, and the old ones are taken away by the master.

There is a rhetorical detail worth remembering here: Don't say "my network is slow", the customer service can easily send you a "line test" and switch to the process of measuring light attenuation. If the light attenuation is normal, you will be billed. If you say "the cat has only been around for four years, it gets stuck again after a few days of recovery after restarting, and the number of connections is high during peak periods", you can lead the symptoms to the equipment, and then the master will bring a new cat to your door. Things to copy before and after replacement (LOID, VLAN, voice parameters) before The article about copying parameters of light-changing cats There is a complete list, and the master has the tools to register himself, but just copying it will make you feel at ease.

Incidentally a reminder: Some people are worried that changing to a new cat will wash away the modified configuration, and they are right to worry. When the new cat is re-registered in white box state, all the bridging and WiFi settings you have changed will be lost. ITMS will push it back to the default. This is the operator's remote management at work. The principle is TR-069 article . So after changing to a new cat, the work of changing the bridge needs to be done again.

Solution 2: Change bridging and let optical modem only do translation

If you have a lot of equipment at home and a strong willingness to mess around, another way is to change the optical modem to bridge mode, so that it can only do "optical-to-electrical conversion" and leave all dialing and distribution to the router. This is what optical modem is supposed to do - its part-time job as a router is a free job, and it is excusable if it doesn't do it well. This division of labor is accounted for The article about optical modem tube translation router tube distribution The inside is cut very finely. After changing the bridging, all the connections are placed on the router, and the small chip of the optical modem is released. Two thousand eight sessions are not a big deal for a serious router.

But the threshold for changing the bridge is much higher than calling customer service.: Super passwords are required, VLANs need to be copied, problems may occur after changing the landline and TV, and the RMS may be pushed back in the middle of the night. Countermeasures for a moving cat being pushed back in Obtaining the super password is only the first step , the overall process of changing the bridge and the pitfalls of each company (please delete the original article and add one) are in The article about China Unicom changing its bridging . Don’t panic if the dialing fails after changing it. The computer is directly connected to the optical modem and you can manually dial it to know whether it is the configured pot or the line pot. The number of channels is The article about dial-up failure after bridging .

There is a middle way: Without changing the bridge connection, move the smart home to the router's WiFi as much as possible, and directly turn off the optical modem's WiFi. The equipment is still the same, but it all comes out through one port. There is one less layer of wireless tossing inside the optical modem. The power and capacity of optical modem WiFi are here The article about weak WiFi signal of optical modem After all, the hardware foundation of the two antennas is there, and you shouldn't count on it. In addition, operators in some provinces will block the number of devices connected to the optical modem. If the number exceeds the number of devices, new devices cannot be connected. That is another set of restrictions. It has nothing to do with whether the performance card is stuck. The solution is The four-station limit article .

How to choose between two paths, end with one table

Let’s go through this matter in terms of “what to do first and then what to do”:

My advice is to be simple and direct: The optical modem is rented, and it can be replaced with a new one after four years without spending a penny. The heavy work is left to the router. This is the correct solution for most families. Changing the bridge connection is suitable for people who have soft routers or high-end routers and dozens of devices at home. It can be done in one step, but it also requires a lot of care. Finally make an account: That new router costing more than 400 yuan was not a free purchase—the old one was indeed old, but when I spent the money, I still hadn’t figured out that the real problem was the iron box in the weak current box.