Power of Wireless Backhaul – Adding Connectivity Muscle to Networks

By Zia Askari | TelecomDrive.com

Future Microwave Networks will Become Fully Programmable and Responsive

As telecom networks continue to add more number of devices – they are under continuous stress to meet with next generation consumers who need mobility and seamless integration of their devices. In such scenario strengthening of wireless backhaul can add much needed muscle power to an operator’s network.

In an exclusive discussion with Zia Askari from TelecomDrive.com - Olivier Gueret, Microwave Product Marketing, Nokia discusses various aspects of wireless backhaul and how this can help operators do more with less.

At a time when consumers are always looking forward to better experience and extreme mobility – it is all about delivering HD content, videos etc. In such scenario, how can wireless backhaul help operators deliver great experience as well as mobility to its customers?

Today, more than 50% of base stations are connected with microwave and this will remain the technology of choice when fiber is not available. Microwave links are fast and cost effective to deploy, even over long distances. Microwave is therefore a key technology for backhaul and represents a worldwide market of about 4B$.

Microwave will continue to play an important role simply because they will remain the most straightforward way to bring fast the capacity where it is needed. Of course, capacity remains the key issue. Standards do not allow today to reach super high capacities.

It is a very regulated world and standards are evolving to cope with the extra large capacity requirements with very high frequencies (above 100GHz and up to 140) and with capabilities to bond multiple links together to provide extra distance, extra capacity while maintained high reliability.

But beyond this ultra-broadband view, new demands and innovations will be driven by Internet of Things and 5G with a mix of low throughput traffic generated by billions of devices and super high throughput, low latency traffics.

Transport networks will have to be more agile and more reactive to these new requirements. SDN will certainly help orchestrate and program microwave transport networks to address those new requirements.

What are some of the big trends that are happening in the Wireless backhaul space that can help telecoms move up the value chain? What is the strategy being adopted by your organization?

If we look at the broader picture of network architecture evolution, there are several clear trends: first, network functions will be increasingly virtualized (NFV), hosted and managed in the cloud. Second, services will be managed end-to-end across the network (network slicing).

Third, this multitude of services and functions will be dynamically created, optimized and terminated. As said above, this means that transport networks will have to be more responsive to these changing requirements, with the ability to address multiple and sometimes contradictory requirements.
We believe that the answer is a combination of “Carrier Aggregation” and SDN.

Carrier Aggregation denotes the combination of several physical radio links with different characteristics into a single logical channel. For example, a channel in the 80GHz band (millimeter wave) providing high capacity and low latency can be combined with a traditional band to provide high reliability for critical traffic.

Although each individual microwave node can dynamically map the services to the appropriate channel, the end-to-end path computation will be managed by a Carrier SDN solution.
With this, microwave networks will become fully programmable and responsive, and will support operators in their migration towards 5G.

What are some of the innovative solutions that your organization is bringing forward in this direction?

Our Nokia 9500 Microwave Packet Radio (MPR) products support different Carrier Aggregation architectures and support different use cases. In addition to the use case described earlier, we can also combine microwave with fiber, to add capacity or simply backup the fiber.

Our Carrier SDN solution, Network Services Platform (NSP) is already commercially available and our 9500 MPR is “SDN-ready” today.

Today’s customers go for integration of wifi and cellular data – in such scenario how can strong wireless backhaul drive better network stability, flexibility and scalability for operators. Your comment?

There is a strong parallel between what happens on the access side and the backhaul side. Indeed, wifi is the right technology to transmit bursty, non-delay-sensitive traffic (e.g. background download) while cellular will be used for critical, time-sensitive traffic such as voice. The same scheme applies to microwave with the complementarity of millimeter waves and traditional bands as explained earlier.

What are some of the challenges that you see in this space and how can these challenges be resolved? How can existing Backhaul infrastructure be utilized to deliver more to the network?

Definitely, the key challenge in microwave is the availability of spectrum, a scarce resource. This is true from a standardization point of view as well as from a regulation point of view, and this depends on the country.

But there are techniques to make the most out of the allocated spectrum. Just to name a few: cross-polarization allows to double the throughput on a given channel, packet compression allows a 10-30% gain by removing unnecessary headers…

Another typical challenge is real estate: it becomes more and more difficult for operators to find new footprint. For that reason, there is a trend towards full outdoor equipments.

How can operators strengthen their existing Backhaul capabilities in a cost effective manner? What is your experience in this direction?

In almost all cases, microwave will be less expensive than fiber, as you don’t need to dig trenches. As explained above, there are several techniques to get more capacity from a given channel. However, at one point, the limit is reached and the operator needs to deploy more equipments.

The key here is the ability to add more radios (i.e. more channels) to an existing equipment. This is called the “nodal” capability and our 9500 MPR have been designed to allow multiple radios to be added on an existing system.

From an operational perspective, “strengthening” the backhaul means increasing the responsiveness and optimizing the resource usage. This is the role of SDN.

Also, we understand that – under 5G scenario – millimeter waves can play a bigger role. What is your opinion on this as enablement of Millimeter wave can create huge difference when it comes to cost effectiveness of strengthening of backhauling?

Fully agree with this statement. For the reasons explained above, we believe millimeter waves will play a big role in 5G backhaul, if properly combined with other bands and managed by SDN.