Wireless network card capabilities

Wireless network card capabilities

[James Courtier-Dutton]

Hi,

Can Wireless network cards receive and transmit on two channels at once?
I am thinking of implementing a way for a wireless VoIP phone on Linux 
being able to hand off from one AP to another without dropping the call.
For this to work, the wireless card must be able to chat on two channels 
during the handover, so as to not loose any voice packets.

James

Re: Wireless network card capabilities

[Ulrich Kunitz]

On 07-02-04 10:42 James Courtier-Dutton wrote:

> Hi,
> 
> Can Wireless network cards receive and transmit on two channels at once?
> I am thinking of implementing a way for a wireless VoIP phone on Linux 
> being able to hand off from one AP to another without dropping the call.
> For this to work, the wireless card must be able to chat on two channels 
> during the handover, so as to not loose any voice packets.
> 
> James

The easiest way to achieve this is to use two wireless adapters.
I'm not sure, whether there are adapters, which support parallel
reception on two channels and manage two independent
associations at the same time. 

-- 
Uli Kunitz

Re: Wireless network card capabilities

[Johannes Berg]

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James,

> Can Wireless network cards receive and transmit on two channels at once?

No cards that I know of contain two PHYs which would (afaict) be
required for this.

johannes

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Re: Wireless network card capabilities

[Ashwin Chaugule]

On Sun, 2007-02-04 at 13:27 +0100, Ulrich Kunitz wrote:
> On 07-02-04 10:42 James Courtier-Dutton wrote:
> 
> > Hi,
> > 
> > Can Wireless network cards receive and transmit on two channels at once?
> > I am thinking of implementing a way for a wireless VoIP phone on Linux 
> > being able to hand off from one AP to another without dropping the call.
> > For this to work, the wireless card must be able to chat on two channels 
> > during the handover, so as to not loose any voice packets.
> > 
> > James
> 
> The easiest way to achieve this is to use two wireless adapters.
> I'm not sure, whether there are adapters, which support parallel
> reception on two channels and manage two independent
> associations at the same time. 
> 

Not too sure, but from what I've understood of Channel bonding, maybe
you could bind the 2 wifi ifaces using 2 adapters and linux's channel
bonding modules ?

Ashwin