https://mum.mikrotik.com/presentations/NL19/presentation_6878_1556787638.pdf
Can somebody explain what this chap is doing in basic terms because i find it very confusing and have no idea of any applications for the magic he described.
In short, physical wireless interface can be AP and client at the same time (or more precisely, you configure physical interface to use one mode, and then add virtual interface with the other mode).
So basically be wifi wan on one radio and an AP on another radio? Or are we talking chains??
(probably a good idea to identify what the heck is a chain)
A wireless interface in routeros can be in several modes. Some standard 802.11, like station, ap-bridge or wds-slave, some standard with mikrotik “extras”, like station-wds, station-pseudobridge or station-pseudobridge-clone, and some not so standard, auxiliary or for different protocols, like station-wds. nstreme-dual-slave, alignment-only.
Also, a wireless interface can have “virtual” interfaces, which share the radio frequency and have some other limitations. So you can either use two different interfaces or one plus virtual interfaces. In spite of the confusing statement in the manual that “the VirtualAP will inherit the mode of the master”, the master can be in mode “station*” and the virtuals “ap-bridge”. For me it works better if the “physical” wireless device is the station, as it will look for the right channel automatically. If the master is the AP you will need to “follow” the channel of the AP you want to connect to (described in the document you point to).
For what I know, the whole radio is shared between the interfaces (all chain switch together). It is like the interface switches from one mode to another depending on needs, and the “active” mode/ssid/… controls the radio for a while. In practice it works but see a couple of problems below…
I’m working for my travel router with something like (station, one security-profile and one entry for connect-list):
/interface wireless
set [ find default-name=wlan1 ] band=2ghz-b/g/n channel-width=20/40mhz-XX \
default-authentication=no disabled=no frequency=auto mode=station name=sta1 ssid="" \
wireless-protocol=802.11 wmm-support=enabled
/interface wireless security-profiles
add authentication-types=wpa2-psk mode=dynamic-keys name=myhipstercafe \
supplicant-identity=TR wpa2-pre-shared-key=HipsterCafeKey
/interface wireless connect-list
add interface=sta1 security-profile=myhispstercafe ssid=HipsterCafe
This will make the router connect as a normal station.
This will “share” the connection (create a virtual AP):
/interface wireless security-profiles
add authentication-types=wpa2-psk mode=dynamic-keys name=myap \
supplicant-identity=TR wpa2-pre-shared-key=MySupersecretKey
/interface wireless
add disabled=no master-interface=sta1 mode=ap-bridge name=\
routed security-profile=myap ssid=KRouted wmm-support=enabled
Then you need to add mores security-profile and connect-list entries for sta1 prioritized as you wish.
Of course, you will need bridges, dhcp-client entry for sta1, masquerading, a reasonable firewall… all this stuff
There is one problem: while the station is looking for an AP, it is scanning in foreground, and thus the virtual-aps stop working. I also pointed to a tricky problem that I have apparently more or less solved at: http://forum.mikrotik.com/t/detecting-wireless-roaming/129887/1 This problem appears when your router is something like a mAP Lite powered by a USB bank in the backpack, and you go from one AP to the next one…
Basically he was explaining how can you use the real interface and virtual interface, and from his experience he mentioned which one should be AP wich on Station
So no different from any conceptual use of a two radio AP device. (one to capture signal and one to pass on signal and thus not sacrificing throughput).
Basic idea is the same, you need one interface as client to receive signal from elsewhere and another as AP to broadcast it for your other devices. It’s better to have device with two physical wireless interfaces, but if you were cheap and bought device with only one, it can still work in this shared mode.