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String together two routers, and the wifi on each router is set to the same name, using the same channel, and setting the same password...... Is this seamless roaming?
I got up in the morning and had such a heart-stopping reply......
If you can't afford to buy a watch, you draw a watch on your wrist to show your yearning for beautiful things, but it does not mean that you have the ability to have beautiful things.
In the same way, there are many functions on the network that rely on protocols and hardware to support them, and cannot be "taken for granted" to rely on so-called tricks to deal with them.
Methods like this one in the reply can achieve some degree of "wireless roaming", but it's not really seamless roaming. Both routers have the same WiFi name (SSID) and the same channel settings, so you can draw a block table on your wrist.
Let's do it for everyone:
First of all, set up an AP in iN's own AP management interface, called thisajoke
Then connect a new router to the router, and set an AP name on this router, also called thisajoke:
Both APs use the same SSID name and password, as well as the same encryption parameters.
Let's plug in:
First of all, let's talk about the question of whether it can be used, it is okay to use it, but if we look at the parameters, we will find that there is a little bit of a problem.
Note the RSSI parameter: -59dBm, this is the signal strength, although it is connected, but the signal strength is not good, and the transmission speed is only 68Mbps
For the same AP and the same network environment, we only set one AP name, and the other network characteristics have not changed, and the location of the client has not changed. The signal strength is 8 dBm worse and the rate is 16 and a half times worse. Why is this a problem? Looking at the following parameter "noise", since thisajoke is the same frequency and the same name as the access point on another router, no matter which router AP you are using, the other AP is actually introduced into the wireless system as noise. We avoid background noise in wireless networks, but this approach not only introduces additional noise, but also in a short distance from the room, which is artificially difficult to deal with.
In the end, the quality of the access point was reflected in the problem that the RSSI signal was reduced by 8 dBm and the rate was greatly reduced. This approach is not about improving wireless signal quality, it's about proper negative optimization.
Let's use wireless monitoring software to look at these two access points:
We will find that the signal level of this access point is greatly reduced compared to the original Rihome, which can reach the signal strength of -47dBm in the 5G frequency band, and the signal of the same antenna is reduced to -53dBm, which is caused by the additional noise generated in this way.
Seamless roaming itself is an AC+AP mode technology, which comes from the same AC controller to manage and plan the access points of the downlink APs. One of the key points is that all the following APs need to be centrally managed under the control of the AC. If two wireless routers that cannot be linked, although we can set the wireless name and password to the same, because the APs themselves cannot be managed in a unified manner, the signal "collision" interference problem cannot be uniformly planned and coordinated, and finally can only rely on the automatic channel switching function of the router itself to maintain. For example, in the figure above, an AP has jumped from channel 5 to channel 11.
In addition, wireless roaming is essentially based on the 802.11 k/v/r protocol, which is based on the fact that devices such as APs and clients can exchange information in real time to complete unified coordinated control. Get two routers or more routers, these routers will not exchange any wireless network networking information between them, they will only regard other routers as interference sources, using this method to achieve the so-called "wireless roaming", in Chinese can no longer find any words to describe, can only say - liar!
Writing half of the article, thisajoke's login dialog pops up again
This is because the AP name has just been deleted after the test, and the access point on the other router has not been completely deleted, and you need to enter the password again to access it. Why is that? This is because the system does not only rely on the name of the access point to distinguish the access point, but also by BSSID. Speaking of human language, although the name and password are the same, they are still regarded by the system as two unrelated access points. This is not "seamless roaming" at all, but the signal is not good and is switched to a new AP.