Mobile routers and wifi

[robgendreau]

I was camping with a group and we were musing on the idea of running a local network. I'm wondering if anyone has done this. Part of the reason had to do with sharing photos; many had iOS devices and the only way we could share was a bluetooth app which was impossibly slow. Ditto for an Android phone, although I dunno if there is any way one could run an ad hoc wifi network off an Android device. Pretty sure there's no way to do it off a non-jailbroken iOS device.

One could run an ad hoc network off a computer (at least I could on my Macbook Pro), but the antenna isn't so hot. And I'd have to bring the computer and use the power, etc. But maybe we could make some sort of mini-server out of a computer, and use an Alfa 2 watt USB wifi radio to beef up the range.

There are small 12v routers; those would seem to be a possibility as well.

But in looking at this it seems that even if I get a non-internet connected LAN going, there is a shortage of peer-to-peer options in the mobile world for sharing; I keep running into the necessity of having internet. Does anyone have recommendations for apps that run across Android and iOS that can share files, photos, messaging, and/or email without a server and without an internet connection? Something that is fairly simple so not everyone has to geek out?

For extra credit, there's internet connectivity. Of course we might get it if we had cell coverage. But often one person has it, and everyone else doesn't. If that person has access to an internet hotspot on say Verizon (I don't think ATT offers this although they've been saying it's coming forever) could they share that with the rest of us? I've never used one, so I don't know if that hotspot would work with a variety of other wifi devices. Or could be shared through a LAN via a router somehow. If someone had a cellular modem, then we could use an appropriate router with a USB port (look at the Alfa R36, eg) to share that internet data connection, provided it's compatible (I know, IF it's compatible). Or, maybe use a cantenna and poach a distant free wifi connection.

Anyway, thanks for any advice.

 

[dwh]

I think you're going to need a separate device to act as the first ad-hoc for the non-rooted phones to see and connect to.

On the subject of the Alfa - the problem with running a 2w Alfa, is that it can broadcast a long way. Other devices might be able to receive it just fine - but they won't have the power to talk back so it can hear them. It has good receive sensitivity, but you need a bloody good antenna to pick up the weak signals from far way devices. The Alfas rock for shooting point to point links with directional antennae.

 

[DaveInDenver]

HSMM-Mesh does implement a robust ad-hoc network, although it wouldn't help with WiFi devices since the network is amongst Linksys routers and the devices are connected through the LAN ports on the reconfigured routers. Byzantine Linux attempts to solve this, although I am only familiar in passing at this point since Mac support has just been rolled in. Supposedly smartphones can get onto the mesh if there are hosts available.

http://www.hsmm-mesh.org
http://project-byzantium.org

Up in Seattle they are trying to implement a broadband mesh city-wide. Check out the NW-MESH project.

http://nw-mesh.wikidot.com

For NW-MESH and HSMM-Mesh you have to be a ham to use them.

 

[expedition4x4]

Why go to ad-hoc when you could easily support many devices on an android phone using a hotspot app regardless of uplink access you still have the ESSid and intrastructure mode LAN. I use an app called SVTP on my droid and it doesnt require root.

 

[robgendreau]

Good point about the Alfas. And this does seem like something a MESH net would be handy for, conceptually.

But I'd wanna be even more simple. If I could get a decent WLAN going and then have people use whatever apps allow peer-to-peer sharing, voice, messaging, etc. But it seems, at least in iOS, that most apps I look at require internet/cloud connections even if they are communicating over a LAN. There are some enterprise voice over WLAN servers and whatnot too, but that's overkill.

It's frustrating: you've got these decent (wifi) radios and you can't communicate with them alone. I could do APRS messaging if everyone had 2 meter rigs and the APRS setups, but geez most everyone has a smartphone. The PTT "walkie talkie" apps all seem to also require internet as well. Even if got a small laptop or netbook running as a server I'm not sure I could find something that would allow file, voice, and message sharing. Sheesh.

Rob

 

[DaveInDenver]

I guess I don't see why just running a router with an omni on a pole won't get you the LAN. Getting Internet is obviously more trouble when away from cell coverage, although with dishes it's possible to get 10+ miles point-to-point with stock WRT54G at 19dBm (around 70mW). This month's QST has a story about just such a link used in support of a marathon in Texas. They has an 11 mile 2-hop IP link for a finish line camera using HSMM-Mesh.

http://hsmm-mesh.org/documentation/157-2013-big-bend-50-support

If you open them and heat sink the radio the Broadcom chips are capable of around 250mW, but will burn up if you drive them hard in the case like Linksys assembled them. I think the problem is not a hardware one, but that all these apps are looking for cloud services to figure things out. A basic WLAN would certainly support simple IRC clients, for example, without needing Internet connectivity.

 

[robgendreau]

For just the LAN a powerful router with an omni would work, there are even some outdoor routers that have integrated antennas so you don't have to run coax up a pole, just the power (and many use PPoE). But without a computer server, I'm still wondering how to get much use out of the mobile devices for sharing, voice, etc.

For internet access if you use most routers they can receive the root wifi as WAN and act as an access point, WDS or bridge. But not always as a router. Would work a la MESH if we were attaching a computer maybe over ethernet, but not if we have to get several wifi clients on board. The CPE routers can do this since they take the internet/wifi in on the WAN side, and then set up a secure WLAN on the other. And they often come with good antennas, although sometimes directional.

I was looking at the Alfa R36 mini-router because it would work with the Alfa USB adapter dongle (the Alfa AWUS036NHR, which can use a directional antenna) to receive the WAN front say a semi-distant Starbucks, and then the LAN would work over the R36 with an omni for more local clients, securely. Unlike some of the CPEs it would use two radios and two antennas. And the Alfa AWUS036NHR wouldn't be involved in the LAN at all when there wasn't any internet. Or maybe you'd point it at someones 4g modem or something.

I definitely wanna get interested in MESH though. But isn't it limited to connecting wired clients?

 

[DaveInDenver]

For just the LAN a powerful router with an omni would work, there are even some outdoor routers that have integrated antennas so you don't have to run coax up a pole, just the power (and many use PPoE). But without a computer server, I'm still wondering how to get much use out of the mobile devices for sharing, voice, etc.

Check out the Rootenna and what some of the HSMM hams do to mount WRT54G/GL/GS routers in them. Pretty standard stuff anymore.

http://www.n5oom.org/hsmm/rootenna_project.htm

I definitely wanna get interested in MESH though. But isn't it limited to connecting wired clients?

HSMM-Mesh as defined by the ARRL working group uses repurposed WRT54G routers as radios, based on OpenWRT firmware. So the client computers are wired to the LAN ports and the 2.4GHz links are between mesh nodes. So that would not work for you in this case without a bunch of wired-to-wireless re-adapters. Your devices will see the HSMM-MESH SSID, but it's no longer a WiFi network they can join.

The Byzantine Linux would, though. That is why I mentioned it. Devices booted into it can be servers or simple clients and I understand smartphones can just be clients on the mesh with laptops or any WiFi device acting like hosts. It ultimately also does not help you because you'd be limited to the applications available in the distro and I just don't know much about it.

Personally I'd just find a couple of old junk routers and flash them with DD-WRT or one of the Tomato versions, make one a WiFi router and the other a repeater bridge (which is a part of V24 of DD-WRT). I have a bunch of them laying around from tinkering with HSMM-Mesh, they come in bunches on Craigslist for $10 or $20. I flashed our home RT-N66U with Toastman's version of Tomato, been happy with it so far.

 

[tibfibber]

perhaps take a look at what OpenGarden is doing. I've tried installing the client on 2 or 3 devices, and had some limited success. Creates a bluetooth mesh VPN on available devices.

http://opengarden.com/

http://www.androidcentral.com/open-garden-awesome-idea-poor-execution

 

[robgendreau]

This is getting more difficult (but also more interesting) as I delve into it.

Boaters, for example, have been messing with this for a while since many marinas provide wifi. The ham stuff is great, and I plan to get into that, but it's impractical for my needs. It looks like the simplest set up is as follows:

A wifi router with a beefy omnidirectional anntenna. Essentially this makes a WLAN broadcast to all my buddies. A good example is the Ubiquiti Bullet; it's handy because it's just a dongle that attaches an antenna at one end, and ethernet at the other. And it does PPoE, so aside from the issue of getting a 24v source, it only requires an ethernet cable and a mast. No losses or expense associated with antenna coax. And since it can act as a router, no hassles with long USB cables or drivers; it works with everything.

But what if internet is available via wifi?

If it's just me, then essentially I could also use something like the Bullet, but with a directional antenna to focus on the wifi/internet source. That comes in on the WAN side. If it's just me and a computer, then I essentially use the Bullet like I would a wifi USB dongle/adapter, as a source for the wifi/internet signal routed on the LAN side via ethernet to my computer (instead of USB). Again, using ethernet means PPoe, cheaper cable, and long runs. I could share my computer's built in wifi as an ad hoc network. Not ideal, but easy.

But if I want to receive wifi internet, and then share it, the best solution seems to be two devices: one to receive the wifi/internet, and another to act as an access point. Which one is the router might depend on what devices used. And the AP needs to have an omni directional antenna. Back to Ubiquiti for examples (they seem to make a lot of the most-used products, and their Linux based software seems pretty usable, at least from the extensive documentation available), I'd use say a NanoStation M2 to receive the internet/wifi since it has a decent internal directional antenna, and it would act as a server. It does PoE, so I could mount it on a mast and run just an ethernet cable up. It in turn would be connected via ethernet (again, PoE) to a Bullet, which could also be on a mast, but would have an omnidirectional antenna, and be acting as an AP for the LAN. So:

wifi/internet source>WWAN>NanoStation/router>LAN>Bullet/AP>WLAN>my clients/pals.

This would work, right?

We couldn't use WDS to pass on the wifi/internet because that requires configuration at the source. And repeating it means losing effective speed since rebroadcasting loses half the bandwidth (although this wouldn't be a problem for wired clients). Having a second device and separate routing means some more control generally, and given the cost, probably well worth it. It also means easy connectivity with all sorts of stuff.

What to do with the LAN when we don't have internet connectivity is still an issue. Thanks for the links. With computers, there's lots of things. But iPhones on just a LAN seem super limited in what they can do. I can find surprisingly little info. It's hard to determine even if many of the common "walkie talkie" apps will work without internet; most won't.

I'll keep searching.

 

[xbox73]

For sharing photos etc. in camp, why don't you just set up a wireless home router. Many these days have advanced features. I would find a wireless router with 2 USB ports, and detachable antenna(s).

Then you:
- plug the router into an inverter (extra bonus if you can find a router that runs off 12V to avoid needing an inverter)
- slap high gain omni WiFi antenna(s) on a car roof & attach it to the router
- hang a USB external hard drive or thumb off one of the router's USB ports
- create folder structure on USB external hard drive or thumb drive e.g. \Username1\Photos, \Username1\Videos, \Username2\Photos, Username2\Videos, etc. (may be easier to do this ahead of time, if you know who's going or have regular users)
- give users router username & password
- get people to upload photos & videos they are willing to share into their appropriate user directory via WiFi e.g. User 2 puts their photos in the \Username2\Photos directory on connected USB hard drive
- users can browse hard drive to look at other user's files many different ways e.g. FTP, browser pointed to local IP address of router, File explorer mapped to local IP address of router, ES File Explorer for Android etc.

For extra credit, to add internet access:
- add USB internet dongle (or mobile hotspot using USB tether, if capable) to 2nd USB port on router (no slow down if plugged in directly). Preferably the internet dongle or hotspot also allows for connecting an external antenna, which can also be thrown up on the car roof for improved signal
- if no USB internet dongle (or mobile hotspot using USB tether, if capable) is available, you can bridge/WDS/Wifi via WAN to a mobile phone acting as a hotspot, though that will cut WiFi speeds in half, so direct connection to USB port is preferable

P.S. Internet access sounds nice in theory, if you know the other users well, but it only takes someone (or their kids) watching a bunch of HD movies running through someone's data allowance into overage to ruin the party. Full res DSLR pics & video are bandwidth data allowance hogs too, if someone decides to upload them to the internet, instead of just to the local USB hard drive via WiFi.

P.P.S. You can also now get flash-based WiFi-capable hard drives, like the Kingston Wi-Drive. But that only allows 3 users to be connected at a time, so might not serve a multi-user environment best.

 

[Ryanmb21]

Nerd thread

 

[xbox73]

Nerd thread

̶N̶e̶r̶d̶ Geek thread. Fixed that for ya.

 

[robgendreau]

Hmm. I don't think nerds can be on ExPort, but since car geeks can, tech geeks can as well. And, most definitely, equipment freaks and geeks. Not nerds, cuz they don't go outside. Now if this was a thread about LAN at Klingon language seminars, mebbe.

But maybe the OP is just a dork.

 

[DaveInDenver]

(extra bonus if you can find a router that runs off 12V to avoid needing an inverter)

Those ubiquitous Linksys WRT54G routers run on 12V.

If you go this route and upload one of the open source firmware versions you have crazy amounts of control over bandwidth throttling and all sorts of blocking and filtering for the Internet issue you mention.