long haul wireless with short haul gear

So life has been crazy lately, finding me on the road more often than not, tethering my cell phone whenever I need to get online.

I run an Internet consulting / Infomediary company, so my Internet usage is pretty heavy sometimes, and my network needs are far above what the average end user would be happy with.

I tether as a last resort, because sprint will throttle your connection after you pull the first 5 gigs from the same tower, and in some places (the shop) I’ll hit that pretty quickly…

7 days in fact:

*sigh* I wasn’t even doing anything heavy (no video teleconferencing, streaming, etc.)

I even set windows update not to download patches unless I specifically tell it to. Same thing with antivirus and so on.

Almost 7 gigs in 7 days. 🙁

So I have a couple of dear friends that live nearby, who I do work for now and again…

It seems they are quite happy to exchange tech support for a connection… 🙂

Thing is, there’s a lot of distance, a lot of trees, and a railroad between us, so my old “string cat 5 through the culverts” trick isn’t going to work here.

Looks like all the proper hardware to do this “by the book” is about $300 bucks. 🙁

Hmmm… I used to do a lot of 11 meter (citizens band / cb radio) skip shooting back in the day… so I actually know just enough to be dangerous when it comes to this sorta thing…

Gone are the days of stacked:

and cophased:

(Co-phasing or “stacking” has long been a way to get high gain from antennas. Co-phasing involves placing two (or more!) identical antennas either side-by-side or one over top another (“stacking”) at a certain distance apart (usually a 1/2 Wavelength or more) and feeding the antennas in-phase. The result is 3 db more than just a single antenna.)

Moonraker 6 beams:

60 ft (the legal limit) off the roof of our house on the hilltop outside of Bellingham (during my 11 meter / cb radio days) … but knowledge is knowledge, right? (I had a summer job once :))

So my awesome neighbor has a Netgear WNR-1000-v2 wireless router…
My end is a Linksys WRT54Gv8 / GSv7 running DD-WRT v24-sp1 firmware…

You know, these:

and for under 10 bucks, my local Wal-Mart supplied these:

That’s a pair of “Rubbermaid 16-Cup Dry Food” containers.

I had intended on using a pair of the “Rubbermaid 1776473 21 Cup Dry Food Storage” units, but I couldn’t find them locally, so I went with the smaller ones.

These will require a bit of hacking, but they’ll have less windage, so it may be a win, right? 🙂

So the first thing we need to do here is to cut a mounting block for the router to fasten to, that can then be fastened to the container itself. (Then the mounting brackets can screw into the back of it).

Then I cut some holes for the antenna (and then the cables, as I didn’t want the inside/outside seal to be in the working portion of the antenna, so I had to get the router closer to the top of the container)

This router is their end, so the connections are
1) cable to network switch in the house (blue)
2) uplink from cable modem (white)
3) and of course “power”.

Note that this deviates from my standard “router to switch is always hot pink” and “modem to router is always red” standard of cable color coding (the more important it is, the brighter it is, servers are yellow, mailserver is orange, dialup concentrators are blue, internal workstations are green)

Anyway:

The router is currently mounted to the block with a liberal amount of high temperature hot melt glue. I later pulled the unit apart, screwed the bottom plate to the block, and then reassembled the router, as the glue didn’t hold up when I accidentally dropped it 🙁

With the bigger container, in theory, you can just put everything inside the container and call it a day, but this worked out very well for me, as you’ll see later 🙂

so now to plug the holes and do some weatherproofing…

That’s a length of 2″ abs drain pipe, cut in half lengthwise, and glued to the container with hot melt glue.

It doesn’t have to be pretty, as small as you can make it is best.
Use a couple scraps for the ends, and let it cool for a bit.

Use a very liberal amount of silicone on the antenna holes:

and then do some more hot melt glue filler work:

Just go slow and let things cool off until you have it watertight and reasonably smooth:

Then screw your mounting brackets to the backside:

Those are 2″ pipe hangers, so I can use 2″ abs drain pipe for my mounting mast.
(note that we changed it for this router later, as a mast was really inconvenient at the other end)

Spray paint it white to make it reject heat a bit, camouflage what’s in it, and make it all professional looking…

and we’re done with that one for now. 🙂

Now we move on to my end of the equation (a Linksys WRT54G v8):

That sucks. Version 8 of this router doesn’t have removable antennas. that’s kinda shitty of them, I expected this kinda half assed crap on the comcast supplied Netgear, but on a Cisco product? for shame.

Oh well, not my first rodeo. 🙂

Looks like I need to do a bit of grinding on the case:

So the router can snug up against the top of the housing:

Note that on this one we only need one network uplink (technically didn’t *need* it, but I’d rather not have to go up on the roof an take it down if I have to do anything creative…

This operation should be pretty familiar by now…

So lets go mount them up and see what happens…

The other router is going to be mounted somewhere out there…

On the other side of those trees…

Starting to think I need to replace the safety lens protector on my phone… 🙁

So here’s what my end looks like. That’s a couple lengths of 2″ abs drain pipe (25 ft total)
The other end is shoved into the ground a little bit, and it’s fastened to the eaves in 2 places (my upper and lower roofs overlap right here) both the antenna’s are equal distance from the other end, as best I can eyeball and estimate it…

So lets power this puppy up and see what we get 🙂

So far so good! 🙂

And on to the other end of the equation…

Google earth and my protractor show that my target is about 10 degrees or so off of “parallel to the wall”, so in the above pic my target is almost directly behind me, and since the neighborhood has a policy about this kind of thing, I decided discretion was best… (you have to be *in* the back yard to see this installation at all) so, no mast. Not bad for a power cable, 2 runs of cat 5, and a router in plain sight 🙂

Not the cleanest installation, but it’ll do for now.
Lets go kick the tires 🙂

I’ve been spoiled by DD-WRT (the firmware running on the Linksys) it makes life so much easier. You can find it [here]

(every time I have to do anything with an end user router running stock firmware, it makes me cry a little inside… dd-wrt makes me smile :))

So I head up to the bus, log into the Linksys, and see if it works…

Interesting. So straight out of the gate this works. Both routers can see each other, and are talking ok. Lots of errors, but they all seem to be transmit errors from the Linksys side of things (the Netgear statistics page is next to useless) implying that the Netgear is having some troubles.

The eth1 interface is the connection between the routers, over the long haul hop.

Signal wobbles a bit and it’s really weak, but it’s there. 🙂

I’m frankly surprised this connection is passing data, I have never seen a signal to noise ratio in the negatives that still works ok. Lets see what we can do about that…

So this is a parabolic antenna template, done by Michael Erskine over at FreeAntennas.com
a larger version is [here]

Instructions are simple:

1) Go peruse Michael’s site [here] (you’ll probably learn something :))
2) Download the template.
3) Open in your graphic editor of choice and resize as needed. Note that the Galvanized sheet stock I got at lowes is 12″ long, so if you don’t want to cut anything, that’s a good target size.

MAKE SURE YOU KEEP THE SQUARE ON THE DIAGRAM SQUARE!

4) Print the image out on whatever. business card stock or acetate (document protector) works well.
5) Thank Michael for his efforts [here]

So here we go.

Start by transferring your template to your chunk-of-antenna-support. I used a piece of very solid oak plywood, because I have lots of it, and using it means I can let the screws bend the metal for me.

Then I cut it out with the scroll saw. Use whatever tool you have and you’re comfortable with. This part matters, so make it as smooth and accurate as you can get it.

I cut outside the line a little:

Then I sanded up to the line on the disk sander.

Then off to Lowes for the bits I didn’t have lying around…
Namely the cheapest parabolic antenna reflector I could find without cutting up the cookie sheets 🙂

Since it’s 12″ long, I marked out and drilled 11 holes in it, and started screwing it down.

The screws worked well to make my curve, and this is the part where I learned that I used the wrong sized template. It’s perfect if I trim the edges of the steel off, but they aren’t going to hurt anything by leaving them, so for now they stay (I may revisit this later)

Here’s a shot of the backside, with all the screws in:

Pardon the duct tape, It was raining like only the pacific northwest does, and I need to fiddle the mount.

1) “chunk-of-antenna-support” hits the bulge where the cable cover is.
2) “chunk-of-antenna-support” sits too high on the reflector (the reflector hits the box)
3) reflector is taller than it needs to be.

I’m probably going to make a much bigger reflector and mount the entire router in front of it next time.

Screw it, close enough, lets kick the tires 🙂

*low whistle* so that 88 cents I spent just proved the parabolic reflector works fantastic 🙂

Keep in mind that the Netgear is the only one with a reflector on it, and that it hasn’t been aimed, tuned, nothing. This is wild ass guess at it’s best.

Looks like the connection wobbles slightly, but it’s *way* better than it was.

For those of you who are wondering how I turned that Linksys into a Repeater bridge, It goes a little something like this:

Take your Linksys WRT54-whatever, and make sure it will support DD-WRTV24 firmware or higher.
The “supported device” database is [here]

Please note that this is *not* for wired connections between two routers, it is a wireless connection only.

Your PRIMARY router must be in AP mode (default) with DHCP Server enabled.

Your SECONDARY (DD-WRT-whatever) router will be configured as the repeater bridge.

Restore factory defaults on SECONDARY router

Do a proper HARD 30-30-30 Reset on the SECONDARY router.
30/30/30 reset:
This will clear out the NVRAM and set dd-wrt back to default values:
With the unit powered on, press and hold the reset button on back of unit for 30 seconds.
Without releasing the reset button, unplug the unit and hold reset for another 30 seconds.
Plug the unit back in WHILE STILL holding the reset button a final 30 seconds.

Connect to your PRIMARY router, and set it’s LAN IP to 10.1.1.1
Connect to your SECONDARY router, and set it’s LAN IP to 10.1.1.254
Set your computer to a static IP of 10.1.1.253

On your SECONDARY router:

Wireless -> Basic Settings
Physical Interface Section
Wireless Mode: Repeater Bridge
Wireless Network Mode: must match primary router
Wireless Network Name (ssid): must match primary router
Wireless Channel: must match primary router
Wireless ssid Broadcast: Enable
Network Configuration: Bridged
[Save]

Virtual Interfaces Section
Add
Wireless Network Name (ssid): Different from Primary Router

NOTE: You can try using the same ssid but there are many reports of random disconnects and/or no connection if the ssid’s are the same.

If using the same ssid doesn’t work for you, use a different ssid from the primary router.

Wireless ssid Broadcast : Enable
AP Isolation : Disable
Network Configuration : Bridged
[Save]
Wireless -> Wireless Security
Physical Interface Section
Security Mode : must match primary router

(should be WPA2-AES, as WEP can be cracked in seconds by anyone marginally competent).

WPA Algorithms : must match primary router
WPA Shared Key : must match primary router
Key Renewal Interval (in seconds) : Leave default

Virtual Interfaces Section
(note if you don’t see this section your firmware should be at least v24-sp2)

Security Mode : must match physical interface
WPA Algorithms : must match physical interface
WPA Shared Key : must match physical interface
Key Renewal Interval (in seconds) : Leave default
[Save]

Setup -> Basic Setup
Connection Type will be: Disabled
Set STP for Disabled (Enabled sometimes can cause connection problems)
IP Address : 10.1.1.2 (Assuming Primary Router IP is 10.1.1.1)
Mask : 255.255.255.0
Gateway: 10.1.1.1 (again assuming Primary Router IP is 10.1.1.1)
DHCP Server: Disable
Local DNS: 10.1.1.1 (if IP of Primary Router is 10.1.1.1)
Assign WAN Port to Switch : Optionally enable this to use the WAN port as another LAN port.
[Save]

Setup -> Advanced Routing
Set Operating mode to “Router”
[Save]

Open Services
Disable Dnsmasq
[Save]

Security -> Firewall tab
Uncheck all boxes, except Filter Multicast
Disable SPI firewall
[APPLY]

[Reboot]

Once you have it working, go to the wireless security tab, and set the same type of security AND key for both the primary and the repeater ssids and hit apply.

set your computer back to auto IP and auto DNS if you wish.
(I use 8.8.8.8 and 8.8.4.4 personally)

Your SECONDARY router should now be able to connect wired and wireless clients.

They will receive IP Addresses from the Primary Router.

NOTE: All repeaters, (including this one), will sacrifice half of the bandwidth available from the primary router for clients wirelessly connected to the repeater.

This is a result of the repeater taking turns talking to not just one partner, but to two, and having to relay the traffic between them.

As long as your internet bandwidth requirements are within this halved bandwidth amount there will be little or no reduction in “speed”.

If it doesn’t work properly the first time, check all your steps / settings again, and reboot the PRIMARY router, then the SECONDARY after the PRIMARY comes back up.

So, I finished this project weeks ago, and held off the blog post until I put the parabolic antennas on the Linksys… which I have yet to do because it’s working well enough for now, so here ya go 🙂

-stone

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