Can I make a Wifi router with Arduino ?

Hi, I want to make some king of router (Wifi) so that I will be able to connect tohim with more that one computer.

is it possible?


If all you really want is for your arduino project to be able to be connected to by more than one computer at a time, you can do that without it becoming a router. It "simply" needs to host a TCP (or UDP) service.

Yes you can, but why do you want to use wifi? I think it will be cheaper to connect computers and arduino with Xbees.

Thanks foe your answers, I know its hard to make wifi router from scratch, what I need is to connect 2-3 computer throw wifi that the can talk to each other, no mater of the speed. I thought about Wifi solution because Rf seems to be much harder to communicate beetwin 2-3 computer simultaneously.

thanks again.

Or you don’t know that you can’t communicate simultaneously over an RF link.

I want it to be small, thats all, router is too big. I don't want the connection to be fast, I only asked if I can connect the wifi platform of the arduino and connect to it 2 or 3 computer at the same time. if it cant connect more than 1 connection at time, so may be 2 wifi adapters will be the best solution? or maybe connect for a while and than disconnect and connect to the other device ?

hope I was clear, Thanks again!

I want it to be small, thats all, router is too big.

Why is size critical? Are you trying to hide it from someone?

ok, didn't know that,I thought it use different channels.

I'll try to be more clear.

I want the arduino to control some electricity , and the handler will be some computer that connect to him and talk with him. it will be like a server thats couple of computer can connect to him and control it in the same time.

now, I want to know if it is possible at all.


I haven't seen anything in the requirements that call for the arduino to be a router. Seems to me all you want is for the arduino to be a server.

Is this big?

Do you know that you need some ram and some real processing power to be a real router…

How far away is Arduino "A" from computer/controller "B" from computer/controller "C"?

+-50 meter

What is the RF interference environment? How likely is RF interference?

Principle should not be specific disorders, I believe that while there will be interference , range will be reduced ,so that's fine for me

How fast must it work? Can you overcome temporary interference by sending the command several times?

Fast isn't an issue, The packets that I'll need to send will be from 5KB to 100KB, but most of the time small traffic. I don't need to transfer big files .

Is there a need for status read-back?

what is it? , sorry.

How does computer/controller "B" know that Arduino "A" got the message?

I think he right after B send the info to A, A will send an approval to B.

How does computer/controller "C" know what Arduino "A" or computer/controller "B" is doing?

All adapters can read the traffic, and analyze it and check if its for them by ID.

How important is this "electricity control"? Is this a Life/Safety issue? is it secret so you can't tell us?

It isn't that important, I need to do it for someone , he asked me if it is possible, so I told him that I used to make small robots with arduino. Thats why I thought the Arduino will be able to handle this.

Are Arduino "A" and computer/controller "B" and computer/controller "C" utility mains powered or battery powered?

only the Arduino (A) will be powered by battery, This is my biggest worry. most of the time it will be in idle mode-no traffic at all.

What exactly is the size requirement? We are going to get tired of the game if we keep suggesting things and you tell us "it is too big".

I did not mean to be secretive or missing information Smaller as many good.

This should be a prototype, So I prefer to be as close as possible to reality.

Many thanks again, sorry for the ambiguity,


may be in the future I guess,

but if its too big so for start 500 bytes will be fine.

what do you think ?

ok, thanks, I understand the big picture.

I'll put another question if you please, regardless of size.

Does 2-3 Arduinos (with wifi adapter each) can talk to each other ? I assume its possible for 2 adapters to talk each other, but if there is one more, is it able to make one of them temporary server or something? what will be the right way to handle it ?

What kind of battery should provide each of them so that one would hold a reasonable period of several hours load?

Thank you so much! :open_mouth:

wow, first of all thank you. Thats what I was looking for.

I found on EBay many RF link kits, and its seems very good. waht do yo say about it:

About the battery question, The device is supposed to Receive information all the time and send an average of 15 broadcasts every hour(a short MSG like you said-500bytes). How long do you think a 9V Batt should hang ?

Thanks again!

I know that you mean I have to program a modem that can encrypt and decode all the information, and you're right, I really lack of time for this. but it seems like they give me a ready lib that do all the oprations:

and for the power story, I think over one day will be more than satisfy for me.

This seems like a perfect application for an xBee (Series 2) network, and with sleep mode, their power requirements are quite low. Whether the price is acceptable, that’s your call. If you are interested in xBees, check the Faludi book (

to have severial wireless devices wotk together, if using internet connections like wifi and ethernet, all you have to do is use seperate ports like Arduino A to Computer B uses port 8080, and Arduino A to Computer C uses port 9080, where port is like a socket (i.e. - http is port 80 and telnet is port 21), I could write a quick example for using one ethernet shield two computers with custom software and using handshaking, you know, if you want one...