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ryansbrother · 3 years

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Wi-Fi manufacturers will not tell you the pit, no longer be deceived when buying a router!

I. Introduction

Some time ago, several original articles about the guidance of the wifi network coverage deployment plan released by the original poster were very well received. Thank you all for your support and love! After carefully reading the comment area of the article, the host found that many friends did not know the concept of wifi very well. When buying a router, they were often overwhelmed by the manufacturer’s propaganda. What wifi6, AC, AX, MIMO, What do Mesh and 1900M mean? Why some products also advertise the maximum speed of 1900M, but the price is several times different? The host below will answer for everyone one by one.

Understand the meaning of wifi parameters, become a wifi expert yourself, and choose the most suitable router product for you.

Of course, the host will also comment and recommend products at various prices on the market.

2. What are the common parameters for purchasing a router?

1. Wi-Fi protocol standards-b/g, n (4), ac (5), ax (6)

When purchasing a router, the first thing we noticed is the wifi protocol standard. Simply put, the standard we call "Wi-Fi" is formulated by a business alliance (WIFI ALLIANCE) formed by a number of network equipment manufacturers. At present, the standards supported by mainstream routers on the market are generally 802.11n, 802.11ac, and 802.11ax. Because the term 802.11ac is not conducive to the judgment of public consumers (the first few generations), the alliance began to use wifi4, wifi5, and wifi6 this year Refers to 802.11n, 802.11ac, 802.11ax. In this way, the level of the wifi protocol standard is clear at a glance.

(1) 802.11n is wifi4, formulated in 2009, with a maximum theoretical bandwidth of 600Mbps. This is the first time that the 2.4G/5G frequency band is supported simultaneously under the wifi protocol standard. Routers currently on the market that still use the 802.11n protocol standard are generally products within 80 yuan.

(2) 802.11ac, or wifi5, was formulated in 2013. It was upgraded to 80MHz bandwidth and 256QAM modulation standard, which increased the single-stream bandwidth to 433Mbps. For the ac standard that supports 4*4MIMO, the theoretical maximum bandwidth can reach 1733M. . Has completely tied the Gigabit standard of wired networks. However, 802.11ac can only work in the 5G frequency band, and many devices in the home still need the support of the 2.4G frequency band. Therefore, all routers that support 802.11ac are backward compatible with the 802.11n standard.

(3) On September 17, 2019, the Wi-Fi Alliance announced that it has officially launched the Wi-Fi 6 certification program. This means that wifi6 has already reached its goal. And now mainstream manufacturers have already sold wifi6 protocol standard products. 802.11ax, also known as wifi6, will achieve higher-order modulation (1024-QAM), higher bandwidth (160M bandwidth), and more complete MU-MIMO (multi-user multiple input multiple output), making the theoretical bandwidth reach 9607.8M . What’s more worth looking forward to is that Wi-Fi 5 only supports the 5G frequency band, and technically cannot completely replace Wi-Fi 4 that supports the 2.4G frequency band. The latest Wi-Fi 6 standard can work in both 2.4G and 5G frequency bands. In the future, this will completely replace the previous wifi4 and wifi5 standards, and it will be more convenient to apply.

Conclusion: Simply put, when we buy a router, we will not buy it wrong as long as we look for the wifi protocol standard on the product page. Generally speaking, the mainstream purchase of AC standard routers, local tyrants please directly look for the words wifi6 or AX!

2. Wireless rate-a digital game

When we buy a router, we often see words such as 1750M and 1900M in the product introduction. The superficial meaning represents the maximum wireless speed of the router, but is it really the case?

▼We take the common 1750M as an example to explain. For example, ASUS RT-AC66U, you can see the huge 1750M on the product package. You must not simply think that the wireless speed must reach 1750M, otherwise it will be a quality problem.

Let's take a look at how this 1750M came out:

First of all, ASUS RT-AC66U is a dual-band router that supports 2.4G 802.11n and 5G 802.11ac, and supports 3*3 MIMO technology. According to the 2.4G single-stream theoretical bandwidth of the wifi protocol we mentioned above is 150M, ASUS RT-AC66U has 3 streams, which is 450M;

The theoretical bandwidth of a single stream in the 5G frequency band under 802.11ac is 433M, and 3 streams are 1300M.

Finally, we add the 450M of 2.4G and 1300M of 5G to get the bandwidth of 1750M. However, in actual use, 2.4G and 5G cannot be used at the same time in any case. That is to say, a single access device can only have a bandwidth of 1300M at most.

Seeing this, do you understand what a manufacturer’s digital game is? Some high-end routers are most prone to such problems. For example, Netgear R8000 marked 4000M is the result of the superposition of the three frequency bands. Netgear R8000 has 3 frequency bands, 2 5G frequency bands with a speed of 1625M, and 1 2.4G frequency band with a speed of 750M. Add 1625M+1625M+750M=4000M. Even under the conditions supported by the device, the maximum speed can only be 1625M.

Conclusion: The larger the number is, the better, but the moisture is also large, which is not the superimposition rate you imagine, so there is no need to pursue the infinite number of numbers too much, just use it enough! 1750M is basically enough

3. Wireless rate-the bottleneck of the access end

The third point is that we still have to talk about the issue of wireless speed, but this time we will not talk about the impact of the router on the speed, but that the access terminal (mobile phone, computer) is the biggest bottleneck of the speed!

Mid-range router products currently priced at around RMB 500 generally support 3*3 MIMO technology, which means that they basically all start at 1750M, and the maximum connection rate of 5G can reach 1300M. Even some domestic brands of 1750M products can cost about 150 $.

▼The general rate of mid-range routers is above 1750M

It can be seen that on the router side, whether you are a hundred yuan or a few hundred yuan, you can easily reach a rate of more than gigabit.

But so! You will find that most of your wifi-connected devices will never reach a gigabit or more even under intranet transmission, and can only reach a connection rate of 866M at most! Why is this?

This is what the host said is the bottleneck of the access end!

First, let’s review how the rate of 1300M under 5G came from. According to the definition of 802.11ac, the theoretical bandwidth of a single stream under the 80MHz bandwidth and 256QAM modulation standard is 433M, and our router products all support 3*3 (3 Sending 3 receiving), that is, 3 spatial streams, so the theoretical maximum bandwidth is 433*3=1300M (the manufacturer's definition will be rounded).

That is to say, to reach 1300M, several necessary conditions need to be met: 3*3MIMO, 80MHz bandwidth, 256QAM modulation standard

Our access terminals are generally mobile devices, and it is difficult to achieve the 3*3MIMO standard on the antenna due to space constraints . This has led to the fact that almost all wifi antennas equipped with mobile phones and laptops are 2*2MIMO standards. Needless to say, everyone already understands what this means. The router must be backward compatible to communicate at a rate of 2*2MIMO . This is why in general, the bottleneck speed of mobile access terminals is generally 866M.

4. The more antennas, the better-what does MIMO mean?

This question has already been answered by many people, and the number of antennas has no direct relationship with the speed and signal strength. Those with 6 antennas are actually not much different from 3 antennas, they are just some tricks of the manufacturer to fool people. You will find that some high-end routers have built-in antennas. You can't see any antenna, but they are still easy to use. Therefore, the appearance of the antenna does not explain any problems.

▼Wow! 8 antennas are good NB, they must be very powerful! In fact, it is no different from a product with 4 antennas or built-in 4 antennas

But the MIMO we are going to talk about below does have a great impact on speed.

In the above, the host repeatedly mentioned the term MIMO, and many friends must be at a loss. Below we will explain MIMO in detail. MIMO technology has been introduced as early as 802.11n, so MIMO has no advantages.

MIMO (Multiple-Input Multiple-Output) technology refers to the use of multiple transmitting antennas and receiving antennas at the transmitting and receiving ends respectively, so that signals are transmitted and received through multiple antennas at the transmitting and receiving ends, thereby improving communication quality.

MIMO is actually a multi-antenna transmission technology. The transmission speed of the earliest 802.11n (that is, 2.4g wifi) is 150Mbps, but this is only the speed of a single-receiving single-transmit antenna. If multiple antennas can transmit and receive at the same time, the rate can be doubled. . This is the origin of the 2.4G 450M rate mentioned above. It is a multi-antenna transmission technology composed of 3 groups of transceiver antennas, namely 3*3MIMO, so the transmission speed becomes 150M*3=450M.

After talking about MIMO, we can finally say that the focus of this section is MU-MIMO.

The MIMO mentioned above can also be called SU-MIMO (single-user MIMO). Although it supports multi-antenna transmission, it can only communicate with one terminal at the same time. Remember the receiving end bottleneck we just mentioned? For example: your router supports 4*4 MIMO, but your two mobile phones A1 and A2 only support 2*2 MIMO. When A1 and A2 communicate at the same time, the router can only send and receive signals to the A1 mobile phone, although it is not full 4*4MIMO spatial stream, but the remaining spatial stream cannot be used by A2, which causes waste.

▼SU-MIMO is like this, it must pass one by one (picture quoted from Li Jianming Ruijie Network)

MU-MIMO exists to solve the above-mentioned problems. MU-MIMO is multi-user MIMO. It is based on SU-MIMO to increase the mechanism of multi-terminal synchronous transmission, thereby improving the utilization rate of the theoretical bandwidth of the router. MU-MIMO allows multiple devices to transmit data at the same time. This is the example above. Under MU-MIMO conditions, A1 and A2 phones can transmit data to the router at the same time, fully utilizing the 4*4 spatial stream of the router.

▼MU-MIMO is like multiple lanes, you finally don’t have to queue to pass (picture quoted from Li Jianming Ruijie Network)

MU-MIMO is currently a selling point of high-end routers, but it is! But but! But but! Not perfect

MU-MIMO must emphasize "compatible devices". Like the receiver bottleneck repeatedly mentioned by the host above, MU-MIMO has also encountered the same problem. If the receiving device does not support it, there will be no software. More importantly , the MU-MIMO mechanism will only take effect when all connected terminals are compatible with MU-MIMO! This is the giant pit! This is the giant pit! This is the giant pit!

Conclusion: MIMO is a good thing, and the improvement of wireless speed depends on it! MU-MIMO is also a good thing for giant NBs. However, the restricted conditions are too harsh, and the bottleneck at the receiving end will cause MU-MIMO to be directly disabled. Therefore, there is no need to blindly pursue MU-MIMO under the wifi5 standard (except wifi6)

5. What other pits need attention

(1) Gigabit propaganda, 100M Ethernet port

This is generally around 100 yuan products, especially old products. Although the wireless rate supports 1200M, the network cable interfaces equipped are all 100M interfaces, a huge hole! It's completely pit Xiaobai!

▼For this panel of TP, the 5G rate promotion reached 866M. But the configured 100M Ethernet port

(2) Exaggerated propaganda, the king through the wall

The country has a limit on the maximum wifi power, so no matter how expensive a router you buy, the coverage of a single point is so large, don't expect a huge gap in coverage. Even if the coverage is slightly improved, the speed and stability are still lost! This is especially evident in the 5G signal. The mainstream routing coverage of 2.4G signals is not a big problem, but we have now begun to pursue 5G signals. Therefore, the fundamental means to solve the coverage area is to increase multi-point deployment!

(3) Power cat is not as good as your phenomenon

Power cat is a product strongly not recommended by the host, and the user experience is very poor. The actual experience of the host and many friends around me shows that the power cat has low speed, high delay, and poor stability. Basically it has become synonymous with rubbish wifi. If the power cat wants to have a good experience, the requirements for the wire conditions can be said to be harsh to the extreme. First of all, it is not allowed to cross the air circuit breaker, there can be no high-power electrical appliances in the air circuit breaker circuit, and the circuit wire should be very high-quality. Not much to say, it is a terrible tragedy, a personally verified tragedy! ! !

3. Mainstream router purchase recommendation, avoid pits

I have written some of the most basic knowledge points of wifi above, do you understand it? Below we have a direct point, dry goods! It doesn't matter if you didn't understand the above, the host has already screened out the products that are not available for you.

1. Can barely be used, work together enough, roughly enough (0-300)

For brand-new router products less than 200 yuan, basically belong to the barely-usable, fully-used, and roughly-sufficient series. Tenda, Pulian, Mercury, and Swift occupy the most. They are mainly targeted at low-demand users. Generally, the number of stable machines is less than 20. Although it looks cheap and promotes NB, the actual price-performance ratio is not high!

Therefore, at this price, the landlord also recommends "earth rubbish": Newifi3/K2P/K3, which is cheap, with moderate performance, complete third-party firmware, and high playability!

▼The K2P/K3 currently on sale by Pinduoduo is a very good choice!

▼For friends who have large apartment coverage and poor money, you can buy TP-WDR7650. The owner of this router has a detailed evaluation, you can refer to it.

First of all, this router is not really good, but the best choice at this price. The landlord detailed the shortcomings of TP-WDR7650 in the evaluation, which needs to attract everyone's attention:

The landlord's evaluation of TP-WDR7650: TP-WDR7650 is really a very tangled product, "there are as many pits as there are fragrances". His advantages and disadvantages are very clear, the price advantage crushes the entire series of products, and the speed drop, packet loss, and severe fever will indeed affect the experience to some extent. However, if you are a less demanding user, for example, using TP-WDR7650 for your parents is indeed a good choice, which is economical and easy to deploy.

2. The mainstream choice (300-600)

I believe that this price should be the price that most people buy, and there are many good products that can be purchased.

Asus' acrh is 17.469 yuan, and the activity is generally 349. As a first-line brand, Asustek’s reputation is obvious to all. This router is stable, strong in signal, multi-functional, and fast enough.

Although NETGEAR R6400 has been on the market for many years, its reputation has always been strong, and it is a good choice as a quasi-high-end router. And you can flash third-party firmware, and the playability is not small. The activity price is 471 yuan, ac1750, absolutely stable and easy to use as a representative of strong signal, remember to use the Merlin system.

The ASUS ac66u recommended throughout the year comes with ASUS faith bonus and stable and fast buff, and the activity price is about 450. 66U's reputation has been maintained for many years, it is obvious to all, and its strength is outstanding. Both performance and firmware playability are very good

In addition, at this price, you can also choose "foreign garbage"

This type of motherboard is basically a single motherboard. The merchants can flash the firmware by themselves, and sell them with a homemade shell (general solution) and a finished antenna. The price is much cheaper than the same type of licensed product, but the warranty seems to be three months in store. And there may be minor problems: For example, if the EA6400 heat sink is too small, the CPU temperature is too high, and you need to DIY to modify the routing.

3. The choice of mid-to-high end (￥600-1500)

In addition to the tens of thousands of news friends, consumer-grade products at this price are the third traditional first-line brands: Asus, Netgear, and Leader.

ASUS ASUS is widely known for its Merlin firmware, and it uses kind materials (where it shouldn't be shrunk). The graph is stable, and it saves time to buy ASUS.

NETGEAR's typical hardware is good, basically the same configuration as ASUS, and then starting at 10% cheaper. However, its firmware is really bad, and most people who buy netware use it after brushing Merlin by themselves.

Linksys used to be a Cisco subsidiary, and now it is part of Belkin. Now it is back in the domestic market, but the price is slightly higher. You get what you pay for, and it’s good to have one thing to say.

(1) ASUS series

It should be said that in terms of high-end products, ASUS has a very complete product line, ranging from 400 to 2000 products. Whether it is the minimum 500 AC66U or the hideous Octopus AC5300, it fully demonstrates ASUS's strength in consumer routing. .

(3) Linksys

As a long-established manufacturer, Lingshi is still very good. After returning to the domestic market, the price is slightly more expensive than the other two. It is okay to wait for a wave of double eleven and other promotions. The original host used AC6500 all the time because it was produced by Lingshi. Except for the severe fever, everything is perfect. Recently I started with EA8300, and I will evaluate it in detail in the next article.

4. Must be selected by local tyrants (over 1500),

When it comes to this price, just go directly to wifi6, and you can buy it directly without losing the money. In the author's opinion, if it is not for players who have extreme requirements for performance, it is really not necessary.

In addition, friends who have a demand for e-sports can also buy professional e-sports routers, the effect is still improved. For example, the ROG-GT-AC2900 used by the host is such a router designed for e-sports. Low-latency function, if there is demand, it is still worth the money.

▼ Although the price of ROG-GT-AC2900 has reached about 1,300 yuan, for the owner's 155-square-meter house, 2.4G coverage is still not ideal, let alone 5G signals.

▼Its built-in e-sports acceleration is its most worthwhile highlight. It provides three levels of acceleration. The first level is to provide acceleration for ASUS ROG motherboards. The second level is to enable the Game Boost function, using QOS to give priority to processing, transmission and exchange For game data, the third level is WT-Fast accelerator and NetEase UU accelerator.

▼The most worth mentioning is the built-in NetEase UU accelerator, friends who often eat chicken will not be unfamiliar. It can accelerate PS4, Xbox, Switch and other consoles, which is a must for domestic players.

In addition, ROG GT-AC2900 supports up to 4*4MiMO, and the theoretical wifi speed can reach 1576Mbps, which is very powerful. However, you need to have 4^4MiMO device support. In actual wifi speed measurement, it is also the best performer among the landlord's many routers.

Fourth, the end

Subject to space limitations, let's talk about so much for this article. I feel that there is still a lot of content to be introduced. For example, the choice of chip rtl8812au, the purchase of mesh, wifi6, and seamless roaming have not been written yet. Let me talk about it in the next article! If you like this article, don't forget to like, bookmark, and comment on the original poster! Remember to pay attention to the host, and read the second part of the router avoiding pit guide for the first time. The host will continue this article and continue to introduce the unfinished content. Of course, in the next content, what you want to see is just, you can also leave a message to the host in the comment area!

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