What if...?

[Ecks]

Just a question; What would happen if a device with both sd and cf expansion were to simultaneously use a sd-wifi and cf wi-fi card?

[Jacob]

The world would implode on that very spot.

[Ecks]

my thoughts exactly...haaaa

[Aerestis]

It wouldn't happen because no matter how hard you tried, the card wouldn't go into the slot or the expansion would pop out. Or is that even how it works? At any rate, you get it... It just couldn't happen. Otherwise, the world would suddenly implode.

[dean_shan]

What if they had a SD Wi-Fi card, a CF Wi-Fi card, and an internal Wi-Fi card?

The whole universe would impload! 8O

Joking aside, nothing. You'd have to choose one of the network cards to use. The rest would just be sitting there dormant and draining battery life.

[Janak Parekh]

Joking aside, nothing. You'd have to choose one of the network cards to use. The rest would just be sitting there dormant and draining battery life.
Well, if they're both set to the same Connection Manager profile?

Most OSes are designed to handle multiple Internet routes -- generally, they pick one (the first initialized one, say) and stick with it. I'm not sure if CE can handle two wireless cards, though.

Anyway, you won't be able to "combine" their bandwidths -- at least, not trivially. ;)

--janak

[Gremmie]

Most OSes are designed to handle multiple Internet routes -- generally, they pick one (the first initialized one, say) and stick with it. I'm not sure if CE can handle two wireless cards, though.

Anyway, you won't be able to "combine" their bandwidths -- at least, not trivially. ;)

--janak

...Unless you use MacOS X

[dean_shan]

Most OSes are designed to handle multiple Internet routes -- generally, they pick one (the first initialized one, say) and stick with it. I'm not sure if CE can handle two wireless cards, though.


That's why I said that. I was under the impression the CE could only do one network connection at a time.

[dean_shan]

Most OSes are designed to handle multiple Internet routes -- generally, they pick one (the first initialized one, say) and stick with it. I'm not sure if CE can handle two wireless cards, though.

Anyway, you won't be able to "combine" their bandwidths -- at least, not trivially. ;)

--janak

...Unless you use MacOS X

I think MacOS X goes under most OSes :wink:

[Falstaff]

Better than combining their bandwidths would be if they would connect to different networks. That is something Intel has been working on, multiple wireless recievers so you can be walking along and your device will automatically connect to the fastest available connection and continue looking for other connections. That would be awesome.

[Janak Parekh]

...Unless you use MacOS X
I think MacOS X goes under most OSes :wink:
I'm assuming OS X uses the BSD IP stack, in which case it'll have two shortest prefixes (default routes)... and will probably go with the first one it encounters in its routing table. If that makes any sense to you guys. :razzing:

BTW, I'd assume the CE kernel can handle two network devices just fine, but I'm not sure the Pocket PC UI on top of it is designed for it.

Better than combining their bandwidths would be if they would connect to different networks.
Right, but we're talking about two WiFi cards here. You're right, though -- multiple networks are becoming more commonplace, though, and we will indeed see more cross-network collaboration.

--janak

[Gremmie]

Oh, I meant MacOS will combine bandwidths, it just won't stick to one adapter. It'll combine all of the bandwidths--but that only works if the combine bandwidth coming from the adapters is equal to or less than the capable bandwidth that you're hooked up to--that means no doing it with dial-up :)

[Janak Parekh]

Oh, I meant MacOS will combine bandwidths, it just won't stick to one adapter.
Really!? That's actually quite surprising. Is this by design (I assume it is) and do you have a link documenting it?

thanks,

--janak

[Gremmie]

No documentation, just vaguely remember being explained it...I think it was called multihoming, I could be wrong though. As I think more about it, he may have been telling me that it could hook to multiple connections and switch between them seamlessly if one was lost.

*shrugs*

I hope I'm not wrong, even if I am, I prefer my fantasy world of technology, everything just works better there.

[Aerestis]

can os ten combine bandwidths? Or is it not able to? I sure wish I was still an x user. I miss it.

edit: wow, while I asked the question, so many posts were posted. nevermind, heh

[Ecks]

Interesting replies!

[Janak Parekh]

No documentation, just vaguely remember being explained it...I think it was called multihoming, I could be wrong though. As I think more about it, he may have been telling me that it could hook to multiple connections and switch between them seamlessly if one was lost.
What I think is more likely is that if there are multiple default gateways, each individual connection might be able to use a different one. I just asked my officemate, and we looked up the IETF's RFCs. They don't seem to specify one behavior, so this is implementation specific. Some OSes might round-robin, some OSes might use one, and some machines might use line speeds. A quick inspection of two interfaces on XP (on a laptop with wireless and wired connections) suggests that XP actually uses the detected bandwidth speed and prefers a gateway with higher bandwidth to set up the metric costs of a IP routing table. See this link (http://lists.isb.sdnpk.org/pipermail/comp-list/2002-November/001617.html). OS X might use a combination of this where most connections might go to a faster route and a fewer (but not zero) connections go to a slightly slower one.

Anyway, I don't see how it could share two different interfaces over a single (TCP) connection for a simple reason: they have different IPs. No remote server would be able to patch together data coming out of two different IPs. And no switch would allow two interfaces to have the same IP...

Besides, I'm assuming OS X's IP stack is based on Darwin's, which is based on FreeBSD's. Or am I wrong?

--janak