The Making of a 90Km Wireless Link for Mfangano Island’s High-Speed Internet Access
Mfangano Island now has a 1Mbps Internet connection. For those of you reading this over a high-speed cable, DSL, or fiber connection in a developed country this may not sound terribly impressive. However, when you consider the four major challenges we had to overcome to bring this meg of data to a remote island nestled at the mouth of Winam Gulf in Lake Victoria, you might think again as to the level of this accomplishment:.
- A small local NGO that had never before worked in the telecom space had to figure out how to design and build a tower that could be welded by local craftsmen to tight technical specifications
- The tower they built supports one end of a 90km wireless link (60% of which is over water), pushing the limits of long-distance WiFi’s capabilities
- The whole operation is powered by a hybrid solar/wind electrical system, because no other power is available at the tower site
- Finally, every single piece of equipment required to put this all together had to be ferried to the island in a small wooden boat and hand carried up a grueling two hour hike
How it all began
I am Andris Bjornson, Inveneo’s CTO and I first met the staff of the small Kenyan NGO Organic Health Response (OHR) two years ago when OHR asked Inveneo’s Eric Blantz to have Inveneo come to Mfangano Island to conduct a survey to assess creative options for bringing Internet to the island.
When OHR’s director and founder Chas Salmen started the organization, his first meetings were on a beach where he gathered ideas about what issues Mfangano Islanders felt were most important. One thing kept coming up over and over again: “We want Internet.” And so Chas focused OHR’s energies on brining Internet to Mfangano Island in a way that would help the local population.
Cellular data coverage is generally good in Kenya. By “good” I mean that in urban centers you often find 3G speeds, and that slower EDGE data is fairly widespread in the countryside. Mfangano Island is an exception. It lies 50 km off the Kenyan shore of Lake Victoria, and providers have been hesitant to build towers on the island because of its remoteness and the unique challenges of making long links work over water. Instead, Islanders must rely on distant mainland cell towers, resulting in connections that continually drop out, and speeds that are slow for one user, and truly glacial when shared among multiple computers.
On that initial survey, I hiked Mfangano from top to bottom with Robinson Okeyo and Brian Mattah. I conducted a standard Inveneo wireless survey: taking GPS points, pictures and notes. I learned that the highest point on the Island was considered sacred ground (and obviously an inappropriate place for an antenna) because it was where the very first man to inhabit Mfangano built his house. I saw beautiful Kenyan sunsets across rustling maize fields, with the expanse of Lake Victoria as a backdrop.
The OHR model
The main thing I came away from our initial survey with, was a deep respect for OHR. I have never met another small NGO with as much heart as OHR. Every member of the OHR team I worked with, most born and raised on Mfangano, is committed to the success of the organization on a very personal level.
OHR is primarily focused on delivering social services to the community around HIV/AIDS issues. Kenya’s Suba district has one of the highest HIV infection rates in Kenya, estimated to be between 25-30%.
OHR came up with the unique idea to start the Ekialo Kiona (EK) center. Ekialo Kiona means “Whole World” in Suba, the local language of Mfangano Island. The EK center is a well-equipped computer center, library, and training facility, and it’s free for all the residents of the island to use.
The only condition for access is that users must know their HIV status, current within 6 months. The EK center runs a testing and counseling center in the building across the hall from the computer lab, and issues identity cards to all EK center members. These cards not only grant access to the EK centers resources, but also help with the process of referring HIV positive members to the right treatment and care facilities.
Building the tower
Returning from the survey visit, I plugged the GPS points I’d captured into RadioMobile, the open source link planning software Inveneo uses to do WiFi analysis. RadioMobile uses freely available terrain data captured by the space shuttle to create a three dimensional view of the project area. It combines that with radio propagation models to let us analyze possible antenna locations for WiFi links.
Based on this analysis, Inveneo came up with two options for OHR: lease space on a Kenyan cell provider’s tower on the mainland, or build their own 20m mast high on Mfangano’s Soklo Mountain, and attempt a whopping 90km link all the way back to the province capitol city of Kisumu where high speed internet is readily and affordably available.
OHR, wanting to invest in small Island welders and fabricators as much as possible and to avoid the recurring costs of leasing a tower, chose the second option. OHR also found the mast construction option attractive because it would enable them to setup a community FM radio station to inform Islanders about their services. I have to admit; at the time I was skeptical of OHR’s ability to pull together a 20m mast safe enough for me or other Inveneo engineers to install equipment on, and to get it in exactly the right spot. Then again, I didn’t know OHR’s determination and work ethic as well then as I do now.
With Inveneo’s advice, OHR took on negotiations for the land we’d identified as the “sweet spot” for the tower. Sorting that out involved discussions with the father who owned the land and his two sons he’d divided it between. OHR’s local buy-in was critical here, as we later found a large Kenyan cellular provider had tried and failed to negotiate a land use deal with the farmer. OHR also secured an agreement with the owner of the tallest building in Kisumu to mount a pole and dish on their roof.
OHR did research and consulted with mechanical engineers to come up with a design that could be built by Island welders in 10ft sections. These sections would later be carried up the only footpath to the top of the Island, bolted together, and fitted with tight guy wires.
OHR next had to learn about proper grounding of radio masts. For obvious reasons, tall metal objects on high points tend to attract lightning. Tower grounding involves building a copper cage of sorts out of multiple rings of copper wire buried at the base of the tower. A lightning rod must be mounted high on the tower, and tied into the copper cage. This is essential to be sure sensitive electronic equipment on the tower survives lightning strikes unharmed.
The final step before construction could begin was to sort through the regulatory issues, and particularly in Kenya this is no small feat. Communications, aviation, and environmental regulatory agencies had to be contacted, forms had to be filled out, and fees had to be paid.
OHR navigated all these hurdles with remote technical input from Inveneo and many others, but to keep costs down and to make sure the OHR team was intimately familiar with the details of the project, OHR local staff handled the bulk of the discussions and negations.
A unique wind/solar power system
With the tower in place, OHR just needed electricity. After all, there aren’t exactly wall sockets sprouting out of the corn fields. Mfangano Island does have a small gas burning power plant (essentially a building sized gas generator). However, distribution wires and power poles haven’t been run around the perimeter of the Island yet, let alone to the top of Soklo Mountain. Kenya Power could be paid to install the wires to the mountaintop, but install fees would be enormous, and maintenance would have been extremely challenging.
OHR enlisted the help of a Kisumu-based organization Access Energy, started by Sam Duby. Inveneo has always prioritized low power equipment, and the WiFi gear we needed to install at the tower would only require 24 watts to operate 24/7. However, FM radio transmitters are a different story and are inherently power-hungry. Access Energy built a hybrid solar/wind system consisting of a panel and two locally fabricated wind turbines. Sam’s turbine mast design uses hinged, guyed monopoles. These are far easier to put up than climbable masts because turbines can be assembled before the whole pole is tilted into place. This doesn’t work for WiFi, though, because high gain dishes must be carefully aimed by a person on the tower to ensure a strong signal.
Preparing the WiFI connection
With all the prerequisites in place (tower, licensing, power), it was now time for Inveneo and our Kenyan ICIP Setright Technologies to deliver on our promise to get the WiFi link up. I definitely had a few butterflies when it came time to deploy. I knew the science was sound, but long WiFi links over water present unique challenges.
Water and land heat and cool at different rates. This in turn keeps the air above at different temperatures. Every time radio waves cross a temperature boundary, they bend slightly. As the air temperature changes throughout the day, this can make the ideal antenna position for, say, 6am vastly different from the ideal position at 6pm. Talking to others, it seemed that one of the key factors was whether the ends of the link were high up (good) or very close to the edge of the water (bad). In this case we were in luck, because both ends of the Mfangano-Kisumu link were quite high above the water.
Inveneo uses wireless equipment primarily from an innovative California-based company called Ubiquiti. Ubiquiti gear is rugged, easy to use, high performance, and at a far lower price point than many more traditional telco manufacturers equipment. Inveneo selected Ubiquiti equipment for the Haiti Rural Broadband Network that spans 30+ towers across virtually the whole country of Haiti.
For the OHR project, we chose Ubiquiti’s RocketM5 radio paired with their largest dish: the .9 meter, 34 dBi RocketDish. We fitted the dish with a radome: an aerodynamic cover that turns it from a wind-catching scoop into a smooth bubble. This change in wind resistance literally cuts the wind loading on the tower in half: a critical factor when putting such a large dish at the top of a skinny-guyed mast.
I’ve come to realize recently that something like 85% of implementing ICT projects in developing countries is proper logistics. The technical work itself isn’t all that challenging, but if you get to a place like Mfangano and find you don’t have the proper tool or spare piece of gear, you can quickly find yourself in a non-workable situation.
Once the equipment arrived in Nairobi, Setright shipped it to Kisumu. Sam Perales, one of Inveneo’s Project Engineers, and I traveled to Kisumu in late May this year to install the link. The plan was for Sam to remain at the Kisumu end of the link, managing the team installing the dish on top of the 18-story Province Headquarters building. Inveneo has learned from experience that with any link over about 40km, it’s key to have teams at both ends simultaneously to fine-tune the aiming. We found once we arrived in Kisumu that the 18 story building had never been fitted with elevators, so Sam’s team had to carry hefty pelican cases and the large dish up 18 flights of stairs. Sorry Sam!
I can honestly say Mfangano is one of the most remote places I’ve ever been. To reach Mfangano Island from Kisumu, I traveled by SUV to Luanda Kotieno, and from there by small car ferry to a spit of land called Mbita. The last hour from Mbita to Mfangano is done by wooden fishing boat. For the final two hours to the top of Soklo Mountain, travel by foot up the rugged footpath through the jungle is the only option. It’s a journey that’s challenging without a few hundred pounds of tools and equipment. Adding that in it makes for hot, sweaty work.
OHR rounded up a group of 6 strong guys to help us get the gear up to the tower. I can only imagine what it was like to carry the even heavier tower sections up there. OHR’s project coordinator, Robinson, was a whirlwind of activity as he arranged all aspects of moving the equipment. His rapid fire approach has earned him the nickname “Marucha” (speedy, in the Luo local language) and it’s certainly an apt moniker.
Day 1 of making the 90Km WiFi connection
With myself, Edwin (an engineer from Setright), the OHR team, and all the right equipment finally at the base of the tower, it was time to get to work. From our time in Haiti, and our recent month long deployment of a medical records network for AMPATH (also in Kenya, further north) we’ve got this part of wireless installation down pat, and the work flows smoothly. We have beautiful sunny weather and a cool lake breeze that’s pleasant up on top of the tower.
Through our partnership with the tower safety experts Petzl, Inveneo has learned a few tricks for rigging hauling systems that makes the task of getting a heavy dish to the top of the tower easier so that went like clockwork. Through Petzl’s generous support, we were also able to donate a climbing safety kit to OHR and train them on its use. This will enable the OHR team to safely carry out any necessary repairs or replacements.
The physical part of the install (hoisting the gear, bolting it to the tower, running the cable, and so on) is by far the most time consuming aspect of wireless work. This, and dealing with a few unexpected wrinkles involving malfunctioning power inverters and poles that were too short to hold our dish, took the whole first day.
OHR has two jovial guys assigned to their “emergency team.” The emergency team is the fix-all troubleshooters. In this case, the emergency team was tasked with carrying up a spare inverter and a backup generator from the base of the Island. “Spare” isn’t actually quite the right word. I learned later that the inverter they sent up came straight from OHR founder Chas Salmen’s personal tent, so Chas and his partner, OHR’s Agriculture Coordinator Jenna, would be without power at night until the permanent replacement could be arranged. Thanks Chas and Jenna!
With day one complete, we headed back down the trail at 6pm finishing the steep hike by headlamp-light. I was excited to know that the following day would be the moment of truth when we would light up the link back to Kisumu and finally see what kind of performance we’d be able to deliver.
Day 2 of making the 90Km WIFI connection
The second day’s hike was harder than the first, largely due to sore muscles from the day before. Edwin had the bad luck of having bought new shoes just before the trip and was fighting blisters. Fortunately, we’d been able to leave the gear in the small shed at the base of the tower so we were less encumbered at least.
Edwin manned the laptop in the equipment shed, communicating with me on the tower with our Motorola VHF radios. We picked these up for our Haiti work because they’re the standard that tie in with the UN’s radio networks around the world, and they’d come in handy recently on our Dadaab deployment. Amazingly, I was also able to reach Sam in Kisumu 90 km away on the VHF radio. This proved extremely helpful as I could coordinate with both Edwin and Sam in realtime.
We powered up the Ubiquiti radios, got them to connect to each other almost right away, and did a little fine-tuning. This is a painstaking process that takes a lot of patience. It involves the engineer at the base of the tower reading out signal strength numbers as the man on the tower makes minute adjustments to the dish. It’s proven one of the hardest skills to pass on to our partners, and the amount of precision required goes up as the link distance increases. On the OHR project, aiming went very smoothly since Edwin mastered the skill.
I called down from the tower to ask Edwin what final signal strength we’d settled on once everything was locked in. When the answer came back “-52 dBm” I could hardly believe it, and had to ask him to repeat himself. dBm is a measure of received signal strength. The less negative the number the better the signal. I’d been expecting something in the mid-70s or so, and to hear -52 was incredible. That was the moment when we knew for sure that we’d have a stable, high-bandwidth link to the island, and it was hugely gratifying.
Turning on Mfangano’s Internet link
After coming down the tower, we finished the equipment room installation, did final configuration of the router and monitoring server, and tidied things up. The monitoring server is an important part of any wireless network, as it lets you look at statistics on performance of the network captured around the clock.
A few final tweaks to the router configurations were all it took to “switch on” the Internet link. The first thing I did to test the connection end-to-end was Google “Mfangano Island” and up popped a very responsive Google map. Robinson and Brian were impressed with how fast it updated as I zoomed in and out, switching on high-resolution satellite photos of the island.
Getting ready to leave a remote site for the last time is always a little nerve-wracking. You find yourself double and triple checking cables and connections, because you know leaving something unplugged would mean another long hike up to fix it. We again hiked down by headlamp, feeling a strong sense of satisfaction knowing the hardest work was out of the way.
Edwin and I spent our final day on the Island installing the EK center end of the short wireless link to the tower. It’s the EK center where all the computers are and where the Internet bandwidth actually reaches the end-users. Fortunately we’d done our job right at the tower, and the link came right up when we pointed the small Ubiquiti NanoBridge up at Soklo Mountain tower. Edwin ran the installation, and things went smoothly. We also installed a local wireless access point (a Ubiquiti NanoStationM2) in the EK center to make sure laptops throughout the small campus could benefit from the internet).
The satisfaction of a job well done
When I fired up a speed test site on one of the EK center computers and measured a blistering fast 8Mbps, the eyes of all 6 people watching over my shoulder went wide. This is truly one of my favorite moments of a wireless installation: when the high-speed bandwidth reaches the end users for the first time. Word traveled fast, and the EK center’s 10 computers were quickly full. I saw a lot of gMail, some Skype, a bit of Wikipedia, and some Google image searches in just the first 10 minutes.
After putting the finishing touches on the EK center installation, Edwin and I spent a few hours training Brian on the layout and maintenance of the network. We made sure pre-configured spares were handed off and hung a detailed diagram of the network to help with troubleshooting.
Climbing into the fishing boat and speeding away from the Island, I looked up at the Soklo Mountain tower. The large white dish glinted in the orange evening sun, clearly visible from a few km away. I talk a bit with Edwin about all the hard work over two years that AccessEnergy, Inveneo, SetRight, and especially by OHR invested in making that tower a reality…and we both smile. I’m excited to see where OHR takes this project next.
The FM transmitter installation is set to happen soon. OHR will be able to install the radio studio in the EK center, and to stream the audio up to the transmitter at the tower over the short wireless link. With the training and extra equipment we left behind, OHR is already talking about putting in a few more links to reach clinic and school sites on the Island. From what I’ve seen working on ICTD projects, perhaps the biggest factor in long term success or failure isn’t technology: it’s local ownership. Given what I know about the dedication of OHR’s team, I expect this wireless network to be around for a long time