Regular routers are bad news for microwave networks. But there is also good news in the form of microwave routers. Photo credit: Mike Licht, NotionsCapital.com / Foter / CC BY
Mobile network operators (MNOs) continue to reap the windfall of the widespread adoption of smartphones. Mobile data volumes spiked initially and still rise quarter over quarter. Along with the demand for more data throughput from their subscribers, MNOs have to accommodate the greater need for responsiveness closer to the network edge.
While regular routers are good at serving Layer 3 services to mobile users on fiber-heavy backhaul networks, they do not do a very efficient job of servicing mobile backhaul networks that primarily use microwave radio. As it turns out, the worldwide majority of mobile backhaul networks are still based on microwave technology, as regularly updated industry research shows.
What can an MNO with microwave backhaul do to bring Layer 3 functionality to its customers that will handle bandwidth constraints, unique aspects of translating router protocols across the microwave interface and failure detection and recovery, among others?
Aviat Networks has published an article in Mobile World magazine that looks at these challenges of regular routers when used in a microwave backhaul network and proposes possible solutions.
Successful financial trades depend on ultra low latency microwave networks. Photo credit: francisco.j.gonzalez / Foter.com / CC BY
Germany is well-known for its autobahn highway system, where there are no official speed limits. Now there is a new high-speed network that traverses Western Europe from Frankfurt in Germany to London in the UK.
In addition, you may have read elsewhere in recent weeks about low latency microwave networks being constructed in the United States in support of the financial markets. The busiest route there is between the financial centers in Chicago and New York, where microwave can shave off 5 milliseconds off the transmission time along the 700 mile (1,000 km) route when compared to fastest fiber network (13 milliseconds). This saving directly equates to revenue for trading houses that are able to leverage this speed advantage.
In the United States, planning and deploying a point-to-point (PTP) microwave network is relatively predictable and straightforward: acquire sites and avoid interference from other network operators. Where PTP wireless networks cross state boundaries, a network operator need only deal with the national telecom regulator, the Federal Communications Commission (FCC), when obtaining required licenses to operate the microwave system.
But in Europe, this is a very different matter. While trans-European fiber networks have been a reality for many years, a microwave route like London to Frankfurt must traverse several national borders, forcing operators to deal with multiple regulators, with complex negotiations needed for microwave paths that cross national boundaries. For this reason very few—if any—microwave networks of this type have been built, up until now. However, the opportunities offered by the combination of the new low latency sector, along with the performance advantage of microwave over fiber, have now made the case for these kinds of networks compelling enough to outweigh the challenges, and costs, of planning and implementing them.
For a low-latency microwave network servicing the financial sector on the London-to-Frankfurt route, there are a number of major challenges beyond just identifying and securing suitable sites and coordinating frequencies. The difficulty of planning a long trunk route is also greatly exacerbated by going through the densely urbanized region of Western Europe. This results in a constant iteration between finding the right route, identifying accessible sites, and securing required microwave frequencies. To be successful you need all three—a site on a great route is useless if no microwave spectrum is available. All the while, there are other competing providers all trying to complete the same route in the fastest time possible—not only in latency terms, but also time to revenue.
This poses huge potential pitfalls in having to take the long way around, requiring additional sites and links, if a site is not available. The added latency caused by any such deviation could kill the entire project. This race is like no other in the microwave business—whoever is fastest wins first prize, and it is winner take all in this competition. The potential revenue for the London-to-Frankfurt low-latency path is quite staggering, even on a regular day, but on busy days when the market is volatile the potential can be much higher. Operators can plan on recouping their total investment in the microwave network in well under a year. Then once you have the most direct route, compared to your competitors, your problems may not be over, so it can come down to squeezing those extra few microseconds, or even nanoseconds, out of your equipment.
On this particular route there is also one significant natural barrier to contend with—the English Channel. There are only a few ways across that are short enough to allow a reliable microwave path, space diversity protection is a must and only a few towers are tall enough to support these distances. Even though there are no obstacles over the channel (apart from the occasional container ship), towers need to be high enough to allow the microwave signal to shoot over the bulge of the earth. Again, securing tower space at these sites is critical to success, but also obtaining the right to use one or more of a finite pool of available frequency channels, otherwise fiber may be needed across this stage, adding latency. One group even took the step of purchasing a microwave site in the Low Countries to secure it precisely for this purpose.
London to Frankfurt will only be the start for low latency microwave networks in Europe, as there is always a need and an opportunity to provide competitive transmission services to other financial centers throughout the continent. The winners will be those with the speed and agility to quickly seize these opportunities, along with working with the right microwave partner who can help them with the intensely complex business of planning and deploying these trans-national networks, and who can also supply microwave systems with ultra-low latency performance.
We will have more to say publicly on this topic in the near future. Or if you prefer not to wait that long, we would be more than happy to have a private conversation about low-latency microwave with you.
Are you considering building an ultra-low latency microwave network? Then you are not alone. Microwave is quickly becoming the default transport choice for low latency networks. However, building an ultra-low latency microwave network is not simple; there are many considerations. Latency through the “box” is important, but it is not the only factor, and too much focus on this metric may be a distraction. What is most important is end-to-end latency of the link. Aviat Networks recently addressed this topic in a webinar (registration required) and free presentation download and answered three very important questions regarding ultra-low latency microwave technology.
Also in this webinar, Travis Mitchell, Aviat Networks director of low latency business development, and Sergio Licardie, Aviat Networks senior director of systems engineering, consider the best practices for ultra-low latency microwave networks as they explore the techniques, technologies and design approaches necessary to ensure lowest end-to-end latency. They also discuss some innovations to look for in microwave networking to ensure continuous improvement in end-to-end latency performance. Other topics covered include: