Question Reuse of SSID and Password

[prawlings1]

Can I reuse the SSID and password from my old Wi-Fi router on the replacement to avoid having to sign in all my Wi-Fi devices? If not why?

 

[USAFRet]

Can I reuse the SSID and password from my old Wi-Fi router on the replacement to avoid having to sign in all my Wi-Fi devices? If not why?

Yes you can.

 

[kanewolf]

Can I reuse the SSID and password from my old Wi-Fi router on the replacement to avoid having to sign in all my Wi-Fi devices? If not why?

Sure. The reason to NOT do it is that you have the opportunity to improve your network security. By changing the password you know exactly what devices (or people) have the password.

 

[hotaru.hino]

If you do this, make sure the Wi-Fi protection method is the same, otherwise the devices won't reconnect.

 

[prawlings1]

Tech support from Asus, the company that makes the ET8 mesh router that I am transitioning to said that I will have to sign into resign into every device even if I use the same SSID and password that was used on the old router. That is the reason I posted the question. It is a good point that both routers will need to use the same protection method. I'll check that. Also, checking to see what devices are connected is a good idea. Thanks.

 

[hotaru.hino]

Tech support from Asus, the company that makes the ET8 mesh router that I am transitioning to said that I will have to sign into resign into every device even if I use the same SSID and password that was used on the old router. That is the reason I posted the question. It is a good point that both routers will need to use the same protection method. I'll check that. Also, checking to see what devices are connected is a good idea. Thanks.

Now that I think about it, even if two WiFi routers have the same SSID and password, it's likely the computer won't reconnect to one or the other because the WiFi router is also likely broadcasting some unique ID, like its MAC address. And the devices connect via that instead of just the name.

 

[prawlings1]

If routers broadcast their MAC addresses the devices probably won't recognize the new router. That is the reason that I'm looking for input from experts. Asus support didn't provide any information about why it wouldn't work. I guess that I'll just have to try it and see what happens.

 

[USAFRet]

What happens when you tried it?

Either it works or it does not.
But given that you are getting a new router...all you can do is try it.

 

[hotaru.hino]

https://superuser.com/questions/1090790/what-happens-if-two-networks-have-the-same-ssid-and-password

That post seems to suggest that there's more in the Wi-Fi network beacon packet that identifies a unique router. So it's looking more like if you add or replace a Wi-Fi network with the same name and password, devices won't automatically connect to it.

And another thought the more I think about it, this is actually good from a security standpoint. You wouldn't want the capability of someone swapping out a router for a compromised one and have devices connect to it automatically (although if it does use the MAC address as the unique identifier... well...)

 

[bill001g]

So I am too lazy to read that whole post you linked. It is extremely common to have many router/AP all with the same ssid and password. It allows the device to take a very short drop and switch to the other radio device. So someone who had wifi on both floors of their house and they could go upstairs and it should switch. All the wifi router/ap are running indepenently they do not even really know the other routers/ap exist.

It doesn't always do the best job of switching but it mostly works. Now the mac of the multiple devices will be different and this is why it take a very short drop when it switches. It will recalcuate the encryption keys which have the mac address. Note these are what is called the session keys not the "password" on the SSID which is just the very first step in connecting encrypted wifi.

In your case it sounds like you just want to run 1 router which should be simpler. Worst case you should would have to stop and start the client on wifi and it would connect

I really can't see why this would not work. It might not be wifi though it could be more related to switching the router function itself especially if the different routers use different IP ranges.

 

[hotaru.hino]

So I am too lazy to read that whole post you linked. It is extremely common to have many router/AP all with the same ssid and password. It allows the device to take a very short drop and switch to the other radio device. So someone who had wifi on both floors of their house and they could go upstairs and it should switch. All the wifi router/ap are running indepenently they do not even really know the other routers/ap exist.

The gist of the thread is it suggests if you add or replace Wi-Fi APs, devices won't automatically connect to it even if it's the only one in range and with the same SSID and password. Also someone did a test and they found out that you can't have multiple (or two in their case) Wi-Fi APs act as a poor man's mesh network. That is, the device won't hop to the other AP until the one it's connected to disconnects, even if the other AP has a stronger signal.

And in any case, the device will connect to the first AP it sees that it recognizes. Which implies that a non-ideal AP will be connected to if its beacon packet gets to the device first.

 

[bill001g]

You are mostly correct that is a huge problem with the "roaming" function in end devices. Even most mesh systems do not fix that. The end client unlike a cell phone is always in charge of what it connects to and it many times will pick a non optimum AP.

BUT this is the method that is used by large corporate enterprise installs. So whoever say you "can't" use the same SSID on multiple AP is a fool. If they actually worked in the networking industry they would know that and know the partial solution. It is critical to control the amount of overlap and correctly balance the number of users. Companies do site surverys and carefully tune the output radio power to get proper overlap that allows the device to have the best chanch to roam correctly.

No large enterprise install is going to use silly mesh system that is only used by home users. Some of the enterprise systems are very fancy that allow central control of all the hundreds of AP all on the same ssid. They also support use of enterprise mode which is much more complex to roam than simple ssid password since each user has his own ID and password in addition to the SSID.

In any case the solution tends to be to adjust the roaming aggressiveness in the end client. This tends to be tricky to get right because you either stay connected to long or you constantly drop the connection and then reconnect to the same AP.