• Using a Wifi adaptor as a client and an AP at the same time

    From David Brown@david.brown@hesbynett.no to comp.os.linux.networking on Tue Feb 13 11:46:07 2024
    From Newsgroup: comp.os.linux.networking

    In the interest of proving that Usenet is not dead, and encouraging discussion, I'll ask a question!

    Is it possible to use a single Wifi adaptor as a client on one Wifi
    network / SSID while also acting as an AP for a dedicated local Wifi
    network / SSID?

    I appreciate that this is no problem if there are separate radios (such
    as using 2.4 GHz for the client and 5 GHz for the AP), or when using the
    more advanced Wifi adaptors often found in upmarket routers.

    The expected use here would be with a cheap and simple single-radio 2.4
    GHz adaptor.

    David
    --- Synchronet 3.20a-Linux NewsLink 1.114
  • From Marco Moock@mm+usenet-es@dorfdsl.de to comp.os.linux.networking on Tue Feb 13 12:49:52 2024
    From Newsgroup: comp.os.linux.networking

    On 13.02.2024 um 11:46 Uhr David Brown wrote:

    The expected use here would be with a cheap and simple single-radio
    2.4 GHz adaptor.

    IIRC that won't work.
    Even operating a dual band adapter as client and AP at the same time
    maybe doesn't work because mostly it is not intended to be used that
    way and the firmware on it might not be able to handle that.
    --
    kind regards
    Marco

    Send spam to muell456@cartoonies.org

    --- Synchronet 3.20a-Linux NewsLink 1.114
  • From Dan Purgert@dan@djph.net to comp.os.linux.networking on Tue Feb 13 12:36:20 2024
    From Newsgroup: comp.os.linux.networking

    On 2024-02-13, David Brown wrote:
    Is it possible to use a single Wifi adaptor as a client on one Wifi
    network / SSID while also acting as an AP for a dedicated local Wifi
    network / SSID?

    Yes - see products like the Ubiquiti Unifi lineup that offer "Wireless
    Uplink". Though, these are a product, and I think you might be more
    asking from the perspective of using a regular PC...

    The expected use here would be with a cheap and simple single-radio 2.4
    GHz adaptor.

    Nope, you'll just be able to repeat the existing SSID on the existing
    channel.
    --
    |_|O|_|
    |_|_|O| Github: https://github.com/dpurgert
    |O|O|O| PGP: DDAB 23FB 19FA 7D85 1CC1 E067 6D65 70E5 4CE7 2860
    --- Synchronet 3.20a-Linux NewsLink 1.114
  • From David Brown@david.brown@hesbynett.no to comp.os.linux.networking on Tue Feb 13 13:47:36 2024
    From Newsgroup: comp.os.linux.networking

    On 13/02/2024 13:36, Dan Purgert wrote:
    On 2024-02-13, David Brown wrote:
    Is it possible to use a single Wifi adaptor as a client on one Wifi
    network / SSID while also acting as an AP for a dedicated local Wifi
    network / SSID?

    Yes - see products like the Ubiquiti Unifi lineup that offer "Wireless Uplink". Though, these are a product, and I think you might be more
    asking from the perspective of using a regular PC...

    Yes, these devices have more than one radio which can be controlled independently (that's common for devices intended as AP's for lots of clients).

    The target use would be an embedded Linux card rather than a PC, but one
    where I have full control of the software and the setup for the device.
    I'd have influence over the choice of Wifi adaptor, but not a free
    choice (if the hardware needed is too expensive, we'll have to think of
    a different solution).


    The expected use here would be with a cheap and simple single-radio 2.4
    GHz adaptor.

    Nope, you'll just be able to repeat the existing SSID on the existing channel.


    I know I can do that. And I know the radio can only operate on one
    channel at a time, so the local AP would have to share the channel with
    the external AP. (And I know that sharing a channel like this would not
    be ideal.)

    I have had one Wifi adaptor acting as several different APs / SSIDs, on different nets, but all on a single channel.


    --- Synchronet 3.20a-Linux NewsLink 1.114
  • From Dan Purgert@dan@djph.net to comp.os.linux.networking on Tue Feb 13 14:26:38 2024
    From Newsgroup: comp.os.linux.networking

    On 2024-02-13, David Brown wrote:
    On 13/02/2024 13:36, Dan Purgert wrote:
    On 2024-02-13, David Brown wrote:
    Is it possible to use a single Wifi adaptor as a client on one Wifi
    network / SSID while also acting as an AP for a dedicated local Wifi
    network / SSID?

    Yes - see products like the Ubiquiti Unifi lineup that offer "Wireless
    Uplink". Though, these are a product, and I think you might be more
    asking from the perspective of using a regular PC...

    Yes, these devices have more than one radio which can be controlled independently (that's common for devices intended as AP's for lots of clients).

    They've only got one, it can just do both bands (well, some may have
    multiple chips, haven't taken one apart in a few years to see what all's
    inside :) )


    The target use would be an embedded Linux card rather than a PC, but one where I have full control of the software and the setup for the device.
    I'd have influence over the choice of Wifi adaptor, but not a free
    choice (if the hardware needed is too expensive, we'll have to think of
    a different solution).

    Most APs these days are embedded linux, so it's definitely doable, with
    the right chipset / driver / etc.

    Not so much that it's necessarily "expensive", but that it's a "niche"
    type feature in the consumer market, which might make finding the right
    chip fun.



    The expected use here would be with a cheap and simple single-radio 2.4
    GHz adaptor.

    Nope, you'll just be able to repeat the existing SSID on the existing
    channel.


    I know I can do that. And I know the radio can only operate on one
    channel at a time, so the local AP would have to share the channel with
    the external AP. (And I know that sharing a channel like this would not
    be ideal.)

    I have had one Wifi adaptor acting as several different APs / SSIDs, on different nets, but all on a single channel.

    Oh? Which chipset is that? I've not seen multiple SSIDs supported from
    the same chip in the consumer kit I've got laying about (or maybe it's
    less "the chip" and more hostapd...?)
    --
    |_|O|_|
    |_|_|O| Github: https://github.com/dpurgert
    |O|O|O| PGP: DDAB 23FB 19FA 7D85 1CC1 E067 6D65 70E5 4CE7 2860
    --- Synchronet 3.20a-Linux NewsLink 1.114
  • From David Brown@david.brown@hesbynett.no to comp.os.linux.networking on Tue Feb 13 16:39:13 2024
    From Newsgroup: comp.os.linux.networking

    On 13/02/2024 15:26, Dan Purgert wrote:
    On 2024-02-13, David Brown wrote:

    I have had one Wifi adaptor acting as several different APs / SSIDs, on
    different nets, but all on a single channel.

    Oh? Which chipset is that? I've not seen multiple SSIDs supported from
    the same chip in the consumer kit I've got laying about (or maybe it's
    less "the chip" and more hostapd...?)


    I've done it with OpenWRT on a TP-Link router - cheap off-the-shelf
    hardware. With AP's, you can set up as many as you like when they all
    go on the same channel.

    You get two "wifi-device", one for 2.4 GHz and one for 5 GHz, which
    includes settings like the channel. But you can have as many
    "wifi-iface" setups as you like for each radio, with different AP SSIDs, passwords, and networks. That's how you set up things like an
    "internal" network and a "guest" network from the same device.

    --- Synchronet 3.20a-Linux NewsLink 1.114
  • From Dan Purgert@dan@djph.net to comp.os.linux.networking on Tue Feb 13 16:51:23 2024
    From Newsgroup: comp.os.linux.networking

    On 2024-02-13, David Brown wrote:
    On 13/02/2024 15:26, Dan Purgert wrote:
    On 2024-02-13, David Brown wrote:

    I have had one Wifi adaptor acting as several different APs / SSIDs, on
    different nets, but all on a single channel.

    Oh? Which chipset is that? I've not seen multiple SSIDs supported from
    the same chip in the consumer kit I've got laying about (or maybe it's
    less "the chip" and more hostapd...?)


    I've done it with OpenWRT on a TP-Link router - cheap off-the-shelf hardware. With AP's, you can set up as many as you like when they all
    go on the same channel.

    Yeah, but that's (to my knowledge, anyway) a different chipset than what
    one can normally get in a USB stick (or replacement wifi card for a
    laptop -- i.e. "in the consumer market").

    Then again, things may have changed, and I'm way off base now (used to
    be that way back in 2017/18 anyway).
    --
    |_|O|_|
    |_|_|O| Github: https://github.com/dpurgert
    |O|O|O| PGP: DDAB 23FB 19FA 7D85 1CC1 E067 6D65 70E5 4CE7 2860
    --- Synchronet 3.20a-Linux NewsLink 1.114
  • From David Brown@david.brown@hesbynett.no to comp.os.linux.networking on Tue Feb 13 20:22:18 2024
    From Newsgroup: comp.os.linux.networking

    On 13/02/2024 17:51, Dan Purgert wrote:
    On 2024-02-13, David Brown wrote:
    On 13/02/2024 15:26, Dan Purgert wrote:
    On 2024-02-13, David Brown wrote:

    I have had one Wifi adaptor acting as several different APs / SSIDs, on >>>> different nets, but all on a single channel.

    Oh? Which chipset is that? I've not seen multiple SSIDs supported from
    the same chip in the consumer kit I've got laying about (or maybe it's
    less "the chip" and more hostapd...?)


    I've done it with OpenWRT on a TP-Link router - cheap off-the-shelf
    hardware. With AP's, you can set up as many as you like when they all
    go on the same channel.

    Yeah, but that's (to my knowledge, anyway) a different chipset than what
    one can normally get in a USB stick (or replacement wifi card for a
    laptop -- i.e. "in the consumer market").

    Then again, things may have changed, and I'm way off base now (used to
    be that way back in 2017/18 anyway).


    That's possible.

    I guess I'm just going to have to try some experiments :-)

    --- Synchronet 3.20a-Linux NewsLink 1.114