Tag Archives: Wireless Bridge

Ubiquiti Bridges- Discoveries and Tips

It seems like almost everywhere I go to consult with small networks that have wireless bridge links in use, I run into some model of Ubiquiti gear. My own knowledge with this tier of hardware isn’t all that deep, as I’m used to dealing higher-priced enterprise-grade stuff. That’s not to sound snobby, but more to add context- and I can say that I’m developing a real appreciation for the likes of Ubiquiti Nanostations and such. Now that I’ve inherited a number of these to verify, optimize, or fix, I’ve found a handful of discussion points worthy of sharing.

I’ve had new-to-me customers declare that their links are failing or that the last guy to touch them did something odd to them. In some cases, the bridges are so high up on a building, you have no way to read the model on them, and the customer has no idea whether he’s using 900 Mhz, 2.4 GHz, or 5 GHz. Many of these cases have come to be in their current state from either a shoestring budget, a poor choice of “network guy”, or both. Whether you’re putting in new Ubiquiti bridges or trying to tame existing deployments, here’s some guidance to help you to be successful, based on my own recent experience:

  • Use the Device Discovery Tool. Found at the bottom of the Ubiquiti downloads page, the tool can save a lot of time and frustration for figuring out what model numbers of hardware is in use, firmware version, and IP addresses. One recent use of the tool showed me this:hourigan bridges

Of course, I wasted time and energy trying to get pictures of the labels on the bridges and finding them via arp, etc before I got smart – the discovery tool is a must-have.

  • Use the Latest Firmware. The operating system on Ubiquiti brides is called airOS. Different model numbers use different “latest” releases, and if you look at the picture above, you’ll see these NanoStation M5s are all on v5.5.9. This happens to be the latest available for this model (as I write this). firmware

  • Keep a Spare Handy. For links that don’t cost much, especially when they are deployed off the beaten path, having a spare or two on hand is just good strategy. Again, using the M5 as an example, you can see a spare bridge (and proprietary 24v power injector block) doesn’t take a lot of coin to get into.amazon M5Remember to backup the configs of all of the bridges you support (found in Device pages of airOS software config pages) so bringing a spare to life can be done quickly.

  • Watch That Mast/Mounting As A Frequent Source of Headache. Ubiquiti bridges like the M5 tend to be lightweight, and are often constructed to be mounted with nothing more than tie-wraps. Though simplicity is nice, mounting these things can get you in trouble. I have found them under metal roofs, on flimsy conduit “masts” that wiggle in the breeze, and put up with no regard for Fresnel zone dimensions. This is one place where the cheap gear and the expensive stuff share commonality: they still have to mount solidly, with proper alignment, and in a way that provides appropriate radio line of sight for the frequency in use. Given that 900 MHz is popular in this space, anyone working with them needs to know the difference when it comes to Fresnel calculations for the different bands. that 8 foot pole that you can get away with for 5 GHz isn’t going to cut it for 900 MHz.

The Ubuiti bridges (excluding the AirFiber products and optional parabolic antennas) are remarkable lightweight and easy to work with. At the same time, best practices and wireless networking craftsmanship are still required for link success and minimal downtime. Don’t let “cheap” overtake your approach because of the product set you’re dealing with.

What Ubiquiti bridge tips do you have to share?

Related Post: In Defense of Little Wireless


A New Point-to-Point Bridge, Some Impressive Numbers

Point-to-Point bridges are a fascinating part of wireless networking. As I’ve written about before, both in this blog and for Network Computing Magazine, I have designed and installed a number of links through the years. The rooftop work isn’t my primary gig, but I frequently design, align, troubleshoot, and occasionally install this incredibly enabling technology.

Even if you don’t work on wireless bridge links, it’ easy to appreciate the notion of making network where there is none, and pushing respectable bandwidth through the air thousands of feet, or dozens of miles.

I recently got wind of Cambium Networks, a company that specializes in the bridging side of wireless. Cambium is worth getting to know if you are looking around for bridging alternatives for point-to-point, point-to-multipoint, and other topologies.

Cambium has recently released their latest PTP model, the PTP 650. So what? New bridges get released fairly frequently from lots of companies, right? I found myself hooked by the range claims associated with the PTP 650.

From the release:

 PTP 650 shines in harsh environments: It is able to transmit up to 120 miles (193 kilometers) over water and desert and from ship to shore, and platform to ship. It is the most reliable NLOS (non-line-of-sight) wireless broadband solution on the market for well field automation.

There was quite a more to the PR, and it’s all impressive enough.  The PTP 650 works between 4.9 and 6 GHz, at a variety of channel widths and with different modulation types that can deliver up to 450 Mbps throughput for under $5K. That’s the condensed version. But if you know anything about bridging, anything that claims to go 120 miles wirelessly bares investigation. Lets look at that rate-versus-range thing.

Lot’s of wireless bridge makers provide “link calculators” which help designers know what to expect as they plan new installations. How far can you go with a given hardware set and still get the throughput you’re after? Here’s Cambium’s Link Planner. To cut to it- here’s what Cambium told me when I asked what the 650 could do at different lengths (without external antennas, using the built-ins)-

Example: Line of Sight; 5.8GHz spectrum; integrated 23dBi antenna; 45MHz channel bandwidth
Range (miles)
Maximum Aggregate Capacity
370 Mbps
220 Mbps
150 Mbps
45 Mbps

To me, this is impressive, as 45 Mbps is still a fairly beefy connection depending on what’s on the other end. At the same time, I can’t imagine trying to align a 100 mile link!

Having never used Cambium products or software, I’m not endorsing the PTP 650 here, but can appreciate what it’s out to solve (even a couple miles can be difficult at alignment time).

A Bit About Wireless Bridges

I’ve installed and consulted on a few dozen wireless bridge links, and find this part of wireless to be tremendously interesting.

I’ve laid hands on Cisco’s 1300 and 1400 models, and had a good run with using 1200 APs in bridge mode (although 2.4 GHz in the Syracuse area for bridging is a losing crapshoot anymore). Dissatisfied with the relatively piddly speeds of .11g and .11a bridges, I found the Exalt r5005 to be a nice, easily-installed performer at 80/80, configurable somewhat if you wanna do the asymmetrical up/down thing. Exalt has a whole line, but the r5005 is one that Cisco sells to customers not digging the older stuff.

A trip to Haiti (long story for another day) got me going on licensed, high-speed bridges. Right now, I have a Bridgewave 80 GHz 100 Mbps link running at about a mile, and a licensed Exalt 18 GHz Gig link at about 1/3 of a mile (I love the Exalt interface and ease of config).

Have also spec’d (and helped the unfortunate tech who had to align it) a Bridgewave 60 GHz unit- such a tight beam that you can screw it up by breathing on it.

I have a Ubiquiti AirFiber sitting in the box, waiting for a place to try it, and so far I hear good and not-so-good about this one. But the price is right… Have also dorked around a bit with EZbridge (the sub-$500 complete kit) built on Ubiquity. Interesting stuff, Ubiquity.

Finally, at the recent Field Day 4 event, my new British pal Mark Julier of Digital Air turned me on to Ligowave which he described as something akin to the Exalt r5005 quality (and it has been fantastic) but at a much more appealing price point. I’ll definitely be looking into it.Image

Update- a reader from Mexico passed along an endorsement for Trango- a company I had not yet heard of. Jesus considers them of better build than Ubiquity’s AirFiber at similiar performance and only slightly higher price. I can’t speak first-hand about them, but they have a lot of information on their site. -LB