SOmeting i’ve always wondered when I see wireless ethernet adapters…why are they always USB? (By wirelss adapters I don’t mean a full wireless card, I just mean the small little ones that are “plug and play”, to borrow a defunct term from the 90’s.)
I guess one might also lump PCMCIA wireless cards into this category, though finding a laptop now that is even lacking wireless is rare…it would have to be at least 4 or 5 years old.
But at any rate, the crux of the issue is that most adpaters seem to be for people who have desktops, which more often than not only have hard-wired ethernet cards, but connect to a wireless network and are too far away from the router, or access point, to use a CAT5 cable. So why isn’t there an adpater that gets a wireless signal, but plugs right into the regular ethernet port? I mean…it seems like it would be easier to translate a wireless signal into a regular ethernet one than to translate it into a USB signal and then have the software/OS create a “fake” network card to decode that signal into.
Or am I just too clueless about how networks work and this isn’t actually possible, or maybe they do exist and somehow I’ve never seen them?
From what I understand, you need to be able to tell the wireless shard which frequency to use, which network to connect to, the security key, etc all of which you usually don’t need with Ethernet as you are usually assumed to be physically in a secure location and as such have can be considered to be trusted to a large extent.
As such, you need to have some intelligence somewhere to do the processing, and it is usually easiest to offload it onto the computer itself instead of having to have a separate computer on the device to do it.
Now if you need to connect devices or computer which don’t have the ability to connect to wireless, there are adaptors, usually called print servers which will convert either wireless to USB or wireless to Ethernet, though you usually have to configure them from another computer to connect in the correct way. You can also get portable routers (Such as Linksy’s Travel router or Apple’s Airport Express) Which can if configured in that way act as a bridge connecting to a wireless network and allow you to connect via the built in Ethernet port. These are however cumbersome solutions, and USB or PCI / Express card adaptors will usually be easer to use if possible to do so.
I don’t believe Wi-Fi and Ethernet are even really the same thing. I think that, to do what you are suggesting, would require an extra step of converting the signal to Ethernet the to something the computer can use.
Note that all the wifi boxes are routers. They aren’t modems. They’re essentially a separate computer that takes the Wi-Fi requests, and converts it to Ethernet ones.
I’m sure someone else can give a more technical answer, but I think that’s the layman version.
It’s all about the power supply.
Most (maybe all) desktop computers don’t provide Power Over Ethernet, so any Ethernet to WiFi bridge device would need an external power supply, which is pretty inconvenient. If you were willing to do this, it’s easy to do - you can use DD-WRT and a LinklSys router to make a WiFi bridge.
USB provides power and a reasonable data rate, so it’s the ideal solution.
As pointed out above they exist, and are called ‘wireless access point client’ or one part of a wireless bridge. They do need their own power supply, and have to be configured through a web page, and usually need to be plugged into a router to set it up, after which you can detach it and use it as a stand alone basically WiFi to Ethernet adapter.
Such a device does or did exist, but I’m pretty sure it needed to get its power from a wall outlet.
My son had one - he used it with one of the earlier gaming systems that had an ethernet plug but no support for wifi. IIRC he bought it from the gaming company - they sold it as an option. It was a little bigger than a cigarette pack.
He left it plugged in in our house for quite a while (months) and we noted our wireless router started getting finnicky (guests had trouble connecting). The problems went away when he got rid of the adapter.
Put that in client mode. Or run dd-wrt on a WRT54G and put it in client bridging mode. There are others for gaming boxes, etc. Generally, its less complex and cheaper to just go PCI card or USB. Not to mention in this approach you lose the only ethernet plug instead of one of many usb plugs.
What, and you think the data is transported up the USB cable by unicorns?
The answers above are right – the wireless adaptor needs a power source, and Ethernet doesn’t provide one. There are PCMCIA wireless adaptors (or at least there were – WaveLan was a popular brand.) But since both desktops and laptops have an abundance of USB ports these days, you don’t see those very often anymore.
USB has power supply; ethernet does not provide power
USB participates in “plug-n-play”, the computer notices the device is attached and determines the correct program to run, pulls up remembered sttings, etc. Etherenet assumes anything else out there on the net is its own device, not dependent on the PC;
Also:
-as part of the startup for the USB device, it will create the network conection going through it, load all necessary settings.
-default settings for a network interface are simple; just boot, obtain adddress (or use hard-coded one) and assume you can talk. A wireless bridge (client side) would therefore either have to be preprogrammed by the client and already live to allow the PC etherent to connect; in initial configuration, it would have to be the one to hand out an address to the network card (DHCP), at least until a bridge setup was established (select network name, enter wireless network key, etc.) and then turn off its DHCP functions…
All in all, a standalone ethernet bridge unit is a lot more complex than a USB key, which is the USB equivalent of the ethernet card in a desktop PC. Needs more smarts, more fiddling with the PC, more configuration. Plus, when there is a wireless bridge to the main network, often the person wants to hook that wired ethernet to more than one PC - making the configuration a bit more complex;
So yes, you can buy a wireless bridge (or a pair) but it’s fairly expensive and more complicated compared to the USB.
BTW, AFAIK a WAP (Wireless Access Point) means a wireless to ethernet unit that allows the main network to have more than one radio attached - basically the same as a router but without the WAN port. Many WAPs do allow you to put them into wireless bridge mode to do what you want - hey they got the guts anyway to do it, why not add the option?
One more thing. The devices I linked to are not easily configurable for most people. You need to know some networking to get them configured right, finding its IP, putting your computer on a temporary subnet to first access its web interface, configuring it back, giving it a static IP, getting back on your network, etc.
With USB devices, you get the full Windows wireless manager and its brain dead simple to pick your network, input password, and get online.
