How to choose the router’s Internet access method? There are three types: PPPoE, dynamic IP, and static IP. If you choose the wrong one, you will not be able to access the Internet.

How to choose the router’s Internet access method: Comparison and confirmation of the three modes of PPPoE, dynamic IP and static IP

My cousin moved last week and the broadband was moved from the old house. Before leaving, the installation master said, "The optical modem has been changed to a bridge. You can dial in the router yourself." He bought TP-LINK XDR3030, plugged the network cable into the Gigabit port of the optical modem, connected the mobile phone to the setup wizard, and got stuck when he entered the "Internet Access Method" page. The four options of PPPoE, dynamic IP, static IP, and automatic detection were there. He clicked on dynamic IP. As a result, the WiFi was full and the browser could not open a single web page.

I'll understand when I go over and take a look: The optical modem has been bridged, and the dialing must be done by the router. Choosing a dynamic IP is equivalent to letting the router wait for the optical modem to send the address, but after the bridge, the optical modem has long ignored this trouble. Today I will explain these three methods clearly at once, so don’t get stuck here next time you install or change a new router.

Let’s first lay out the three ways to access the Internet.: Who is the router waiting for to give it an address?

The port on the back of the router that says WAN is plugged into the network cable from the optical modem. Whether it can access the Internet depends on how this WAN port obtains an IP address from the operator that can access the external network. The three ways to access the Internet are three ways to get an address.

PPPoE means that the router uses the broadband account and password to dial the number, and the operator only gives it a public IP after dialing the number. For dynamic IP, the router does not dial, and waits for the upper-level optical modem to send it an intranet address, because the optical modem has already dialed it. Static IP means that the operator has written down the IP, subnet mask, gateway, and DNS for you, and you fill in the addresses one by one.

To decide which one to choose, ask first: Who's dialing now? For optical modem bridging and router dialing, choose PPPoE. ； If the cat has not been touched and dials by itself, choose dynamic IP. ； Only choose static IP if you get the fixed IP address list. I will use this sentence again and again later.

PPPoE: After optical modem bridging, the router must dial up by itself

This is the case at my cousin's house. The installation and maintenance master said "dial yourself", which means that the INTERNET connection in the optical modem has been changed to Bridge, and the dialing task falls on the router. At this time, the router must select PPPoE as the Internet access method, then fill in the broadband account in the account box and the broadband password in the password box.

The easiest thing to make wrong is not the options, but the passwords. The broadband account password is completely different from the useradmin and WiFi password in the backend of optical modem. My cousin filled in useradmin on the sticker on the back of the optical modem for the first time. The router log kept reporting 691. I asked him to look up the broadband account opening form. The account number was the area code plus the phone number, and the password was the one issued by the business office. Within ten seconds after filling it in, the WAN port status changed to "Connected".

There is another detail. PPPoE dial-up will bind the MAC to the optical modem. In some places, if you get a new router and the account and password are all correct, you still can't dial it in. This is because the operator has memorized the WAN port MAC of the old router. In this case, go to the router to find "MAC address clone" and copy the WAN port MAC of the old router, or call customer service to kick the old session offline. I encountered this problem last time when I helped my neighbor change his phone. I wrote down the specific location and operation. Where to set up router MAC address cloning , I won’t repeat it here.

After dialing it up, the WAN port usually gets an intranet address starting with 100.64, 10., or a real public IP, which is normal. Don't think it's broken when you see 100.64. It's very common for operators to have large internal networks. It won't affect the Internet at home, but don't expect to connect directly to home devices outside.

Dynamic IP: The optical modem is still dialing, the router should not take this job.

For most newly installed broadband, the installation and maintenance technician will not change the bridge connection for you. The optical modem will dial up by itself after the installation. You just need to buy a router, plug the network cable into the WAN port, and choose dynamic IP as the way to access the Internet. The router will automatically get a 192.168.xx or other intranet address from the optical modem, and WiFi can be used.

The advantage of dynamic IP is that it saves trouble and does not need to find the account password. The disadvantage is that both the optical modem and the router are doing routing, and the home becomes a two-layer network. You don’t feel anything when surfing the Internet normally, but when you need to do port mapping, DMZ, and NAS external network access on the router in the future, you will find that external network requests first go to the optical modem and then are forwarded to the router. There is an extra door in the middle. If you want to completely solve the problem, most people will change the optical modem to bridge, and then let the router PPPoE dial-up ； If you don’t want to bother, you can still get by by keeping the dynamic IP.

My own approach depends on the situation: I only use the Internet at home, don't bother with NAS and remote, just use dynamic IP, whichever saves trouble. If you want to connect NAS and do remote access, I recommend changing to bridge and PPPoE. I have written this account before, Is it worth the trouble to change the optical modem to bridging? Calculate it once, and you can turn it over when you hesitate.

There is still a pitfall in dynamic IP: The default LAN segment of some routers is 192.168.1.1 , so does the optical modem 192.168.1.1 , the two backgrounds will fight. The router usually changes itself to 192.168.2.1 Or 10.x, but you may type when logging in 192.168.1.1 What comes in is the optical modem, not the router. This is more common when relocating and resetting. How to reset the router after moving I have written the order clearly here.

Static IP: Only used for dedicated lines and rental houses. You can’t copy any of the four-digit numbers incorrectly.

I've really experienced static IP pitfalls, not at home, but at work. The office connected a small local line, and the operator gave me an address sheet.: IP is 172.16.30.18 , subnet mask 255.255.255.248 , gateway 172.16.30.17 , DNS gave two. I asked my colleague to fill in the subnet mask accordingly. He tried to save trouble by filling in the subnet mask as 255.0.0.0 , the computer can get the IP after saving, but no one can get through except myself.

Why? subnet mask 255.0.0.0 It is equivalent to treating the entire 172 segments as the same network. The router looks at the gateway. 172.16.30.17 We are in the same large network as ourselves, but the actual broadcast domain of this dedicated line only has 8 addresses, and the gateway will not respond with this mask at all. Change it to the one on the address sheet 255.255.255.248 , re-save, and it will work in half a minute.

There are four boxes when filling in the static IP, none of them can be empty.: IP address, subnet mask, default gateway, DNS server. Many people miss DNS. As a result, the webpage cannot be opened but QQ can be accessed. ； There are also people who fill in the gateway with their own IP, which is equivalent to letting the router find itself. My stupid method is to take a photo of the address form with my mobile phone, check each box one by one, and after filling it out, first check whether the WAN port status is "Connected", and then open a web page to test.

Static IP is basically not used for home broadband, unless your rental house or apartment is uniformly assigned a fixed address by the operator. The landlord or operator gives you the address list, so you choose a static IP ； I only give you the sentence "plug it in and it will work", that is still a dynamic IP.

Can automatic detection be trusted? I encountered two misjudgments

The first step of many router setup wizards will be to "automatically detect the Internet access method." This function is generally correct, but don't click next step with your eyes closed. I've had two miscarriages of justice.

One time it was an optical modem bridge, but the LAN port of the optical modem still had DHCP turned on. The router automatically detected that there was an intranet address and determined the Internet access method to be a dynamic IP. After saving, the mobile phone can get the WiFi address of the router, and the DNS can also be resolved, which means that all external network traffic is cut off. Manually change it to PPPoE and then fill in the account password to make it normal. Therefore, after automatic detection, it is best to look back and see if the selection it has made is in line with the judgment of "Who is dialing?"

Another time it was a company dedicated line, automatic detection determined the static IP to be a dynamic IP, because the router first obtained a temporary address when detecting the WAN port. In this case, you can only manually select a static IP by address, don't trust it automatically. My conclusion is: The wizard can save you trouble, but after selecting it, you have to take a look at the WAN port status in person. If the status is wrong, change it manually. Don't expect it to be always smart.

After setting up, I can’t access the Internet. Please follow this order and wait for three minutes.

After selecting the Internet access method on the router, if you still have no Internet connection after saving, don’t rush to try the four options in turn. In the following order, I arranged it this way for my cousin and colleagues.

First check the WAN port status ： PPPoE needs to display "Connected" or "Connected Successfully", and dynamic IP needs to get a non- 0.0.0.0 The address, static IP should be displayed as connected. The status page says "Connecting" and "Server not responding". The problem lies in the WAN section.
Check your account number and password ： PPPoE looks at the broadband account password, don’t confuse it with the optical modem password ； For static IP, there is no difference between the four-digit number and the single address.
Check MAC clone ： If you have changed the router and the account and password are still wrong, try MAC cloning the old device first.
Look at the WAN port network cable and optical modem port ： It's plugged into the router's WAN port, not the LAN port. ； The optical modem is plugged into a Gigabit port or a bridge-bound port, not an IPTV port.
After changing, wait two minutes and try again. ： The old session on the operator's side is not released. Sometimes it's either that the setting is wrong or it's too fast. Save the changes and wait two minutes to see again.

Another type is that after making changes on the web page, you save it, and then jump back to the original options later, or the old phone can still connect after making the changes. It's not that the network is broken, it's that the settings haven't actually been installed or the browser hasn't taken effect. The last time I checked that the router settings were not taking effect, the five pitfalls I found happened to be connected to today's line. Router settings changed but not effective Wrote in.

I'll say it again in order: First select the correct method, then correct the account password, then check the WAN port status, and finally open a web page to test. Don't do a factory reset as soon as you start it. Eight times out of ten, you won't need to reset it at all.