The point of this post is to determine the amount of latency reduction possible with a one-box integrated microwave router solution when compared to a two-box (separate router + microwave) offering. By how much does the one box solution improve latency?
Latency is important to all network operators. The lower the end-to-end delay the better it is for all types of applications.
For example, latency is critically important to mobile network operators (MNOs) for LTE Advanced features like coordinated multi-point (COMP) and MIMO, which require extremely tight latency. CRAN architectures are also demanding tighter latency from the backhaul.
In addition, latency-sensitive applications like Teleprotection, SCADA, and simulcast in private markets such as public safety, utilities, and the federal government will greatly benefit from low latency network performance. For other customers, low latency is critical for synchronization and HD video transport.
In many wireless networks, transport engineering looks after the microwave radio function while the IT department has domain over IP equipment. These two organizations started independently and grew separately over many years. It did not seem that there was any problem with this arrangement.
However, it led to the selection of equipment—radios and routers—that worked really well on their own but had no awareness of one another. Not surprisingly, these technology solutions did not perform together optimally.
In South Africa, as in many emerging markets, wireless backhaul has long been a proverbial bottleneck to network growth. Due to cost and logistics, fiber optic technology remains out of reach as a practical solution for most aggregation scenarios, save for urban applications where population density and shorter routes can justify the exorbitance.
Now with the advent of higher speed, higher throughput mobile phones and tablet PCs, higher-order networking technologies are being pressed into service. Standard microwave radio, while cost efficient and effective for crossing far-flung forests, monumental mountains and desiccated deserts with traditional payload such as voice calls and moderate data rate applications, was not designed for the connectivity and capacity requirements of Layer 3 services. Thus, the bottleneck has grown still narrower. Even to the point where standard microwave radio might be hitting its upper threshold for serving mobile broadband.
Technical marketing manager, Siphiwe Nelwamondo, recently sat down with Engineering News, to discuss these issues and the present and future of microwave radio backhaul in South Africa and across the continent. In addition, he delved into how microwave networking is bridging the radio-IP gap for Layer 3 services by running IP/MPLS protocols on converged microwave routers.
As more and more mobile services get pushed out to the edge of the access network, the imperative for Layer 3 will only grow. Even as 3.5G and 4G mobile users who depend on full-IP increase in number, a majority of second- and third-generation subscribers will continue to rely on circuit-based technology. Not to worry, Nelwamondo covers how TDM telephony will be supported in a converged microwave and IP environment.
The full article goes on to discuss how mobile operators will strategize providing enterprise services from the cellular base station with microwave networking, virtual routers and more.
The entire wireless industry is on the cusp of a transitive time where Layer 3 IP services will be needed in the access portion of the network. And the backhaul will be needed to provide them.
Under the pain of restating the obvious, we have all seen the explosive growth of smartphones, tablet computers and other radio-frequency-loving gadgets like e-readers. All these new-fangled high-tech contraptions need Layer 3 IP/MPLS services in the access and backhaul in order to deliver a satisfying, seamless user experience—especially for enterprise services. The question is how will the mobile network operators (MNOs) be able to deliver these services from their thousands or tens of thousands of cell sites?
Typically, the answer would involve deploying a regular router for IP services at each and every cell site. But have you seen the prices of routers lately? Cisco didn’t get to where it is today without having some heavy pricetags attached to all the heavy iron it’s shipped over the last 20-odd years. Suffice to say, it would be a pretty penny if MNOs equipped all their cell sites with their own dedicated routers. So what else can be done, you query?
It just so happens that Aviat Networks’ director of corporate marketing, Gary Croke, has posted an article at RCR Wireless going over what to do in these types of situations. But we’ll give you a hint: the IP router function should be folded into a single multi-service, multi-layer cell site device. Read the rest and let us know what you think.
Come Fly with Me: Aviat Microwave Over-the-Air at U.S. Landmarks (aviatnetworks.com)
The Rise of Tower Sharing in Africa (aviatnetworks.com)
How 2 Microwave Networks Survived Superstorm Sandy (aviatnetworks.com)
What Does it Take to Get the Most out of Your Wireless Backhaul? (aviatnetworks.com)
LTE has been moving more and more to the forefront in mobile cellular networks around the world. Africa, and particularly the Republic of South Africa, is the latest hotbed of LTE rollouts, with the leading country operators of Vodacom, MTN and Cell C coming online since late in 2012. In conjunction with these LTE access rollouts, our technical marketing manager in the region, Mr. Siphiwe Nelwamondo, has been authoring a series of columns on enabling LTE in a leading regional technology media Internet site, ITWeb Africa.
Naturally, his focus has been on backhaul. In the first installment of his series, Mr. Nelwamondo looked closely at the backhaul requirements of LTE. Chief among these requirements are speed, Quality of Service (QoS) and capacity. He concluded that it is too early to close the book on the requisite parameters for supporting LTE backhaul. Part two of the features, he examined the basis on which microwave provides the technical underpinnings for LTE backhaul—especially as related to capacity. More spectrum, better spectral efficiency and more effective throughput were Mr. Nelwamondo’s subpoints to increasing capacity.
Having more spectrum for microwave backhaul is always nice, but it’s a finite resource and other RF-based equipment from satellites to garage door openers is in competition for it. Bettering spectral efficiency may be accomplished by traditional methods such as ACM and might be increased through unproven-in-microwave techniques like MIMO. Throughput improvement has wide claims from the plausible low single digit percentage increases to the more speculative of upping capacity by nearly half-again. Data compression and suppression are discussed. The truth is LTE, while data-intensive, probably will not require drastic measures for backhaul capacity until at least the next stage of LTE-Advanced.
If indeed capacity increases are necessary in the LTE backhaul, number three and the most current piece of Mr. Nelwamondo’s contains additional information. Nothing is better than having something bigger than normal or having many of the standard model. As the analogy applies to LTE microwave backhaul, bigger or wider channels will increase capacity, of course. A larger hose sprays more water. Or if you have two or three or more hoses pumping in parallel that will also support comparatively more water volume. The same is true of multiple microwave channels.
However, the most truly and cost effective capacity hiking approach is proper network planning. Mr. Nelwamondo points out that in Africa—more than some places—mobile operators are involved in transitioning from TDM planning to IP planning. While TDM planning was dependent on finding the peak traffic requirement per link, IP planning allows the flexibility to anticipate a normalized rate of traffic with contingencies to “borrow” capacity from elsewhere in a backhaul ring network that is not currently being utilized. Along with several other IP-related features, this makes determining the capacity a lot more of a gray area. Some operators solve this by simply “over-dimensioning” by providing too much bandwidth for the actual data throughput needed, but most cannot afford to do this.
The fourth and final entry in Mr. Nelwamondo’s series will appear soon on other LTE backhaul considerations of which you may not have thought. Sign up below to be notified when it is available. [contact-form-7 404 "Not Found"]