RAN Capacity Optimization Through IPoTDM Microwave Transport

This brief white paper summarizes how an IP-over-TDM (IPoTDM) approach can facilitate microwave network evolution to all-IP, consolidate the transport and management of circuit- and packet-based wireless network services in a single physical RAN infrastructure, and allow operators to address CAPEX and OPEX cost challenges by leveraging existing TDM transport resources to the maximum extent possible.

Would You Like Breakfast? User Interface Design Choices for Wireless

A full English breakfast with scrambled eggs, ...

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If you are not from the U.S., the number of choices you need to make simply to order breakfast may overwhelm you. Contrast that to my experience staying at a bed and breakfast on a trip to England: I was asked only two questions—both with a choice of “yes” or “no.” Breakfast and Tea. If you are in a foreign country, jet-lagged, hungry and a little parched (thirsty) there is some comfort in being able to simply say “yes” and “yes.”

Having a choice is good but only if you know what you are choosing. If you are in unfamiliar territory, it can be overwhelming to have to choose whether you want Ranch, French or Vinaigrette. Particularly, if you thought that French and Vinaigrette were the same thing. Conversely, it is very disappointing if you want your bacon extra crispy, but you are not given that option.

Challenge of New and Experienced Users

In the world of user interface (UI) design, the challenge is to cater to new users who do not yet understand the choices they can make and at the same time make sure experienced users—who know exactly what they want—have the control they need. For example, the Eclipse DAC GE3 has been a huge challenge to provide a simple and consistent user interface and at the same time provide control over the advanced Ethernet Switch features.

Rolling up groups of settings into default, canned and custom configurations has allowed us to seamlessly provide simple and advanced views. For VLAN configuration, we provide familiar DAC GE “mode of operation” settings for Transparent, Mixed and VLAN (GE and ES compatible) along with a new 1-to-1 mapping of ports to channels. Clicking on them allows you to create and name custom port groupings and selecting Advanced allows full control of the switch behavior.

We also use many diagrams to make it easier to see at a glance how the switch is configured and to help visualize what the settings mean. The VLAN settings are rendered into a small diagram that shows canned, custom or advanced VLAN configuration in a consistent manner.

The challenge of making our user interface universally accessible is ongoing, and we will continue to improve our user interface over time. And I will continue to enjoy my full English breakfast with a hot cup of tea.

Tony Jones
Senior Software Engineer, Aviat Networks

Ethernet OAM Meets Demands on Microwave (Wireless) Networks

Ethernet OAM (Operations, Administration and Maintenance) can help mobile network operators and other transport providers meet the ever-growing demands for increased bandwidth across the backhaul network as well as meeting the equally important demand for quality and reliability of service.

This white paper will look at how Ethernet OAM can help the evolution from TDM to Next Generation Networks (NGN), with a focus on microwave-based NGN radio networks.

Aviat Networks: Official Wireless Transmission Headquarters

The Aviat Networks Headquarters in Santa Clara is perfectly positioned to serve its wireless customers. Watch this video to see the full capabilities of the Aviat Networks North American offices.

Comprehensive Embedded Security in Microwave (Wireless) Networks

The current and ongoing migration toward IP networking on backhaul networks supports rising data volumes, which is increasing the opportunities and motivations for data and call interception. As data volumes rise in wireless networks and their associated microwave backhaul, security has become of greater concern.

This white paper presents a look at security issues, and the broad portfolio of solutions for remediating such concerns for microwave operators.

Security Focus as Wireless Traffic Rises, Mobiles Get More Powerful

Even though microwave communications have some built-in security-like features such as scrambling, narrow beamwidth, proprietary airframe, coding and other factors, it is not very hard for them to be broken by those with the proper expertise. Some vendors even openly offer digital microwave interception systems for “legitimate” monitoring. This and the growing sophistication and willingness of those attempting to break into wireless networks makes a high level of security for microwave more important than ever.

Historically, security and encryption measures were primarily employed by government or defense agencies or by the financial industry to protect sensitive information. But in today’s connected world the issue of network security can apply to any type of communications network, whether it is fixed, mobile or private.

Is Microwave Ready?

In general, microwave packet radio security is a concern. However, there are different aspects of microwave radio protection that must be considered. The information payload of microwave communications is the most obvious part. For operators that participate in the public switched telephone network (PSTN), the main issue is the security of the communications traffic they are carrying. That would involve both voice and data traffic.

Payload Security

Both popular and scholarly publications have been rife with stories of how easy it has become to tap into mobile calls. For example, the GSM code has been ineffective arguably since a hack was announced in August 2009. With GSM encryption broken, degraded or bypassed, mobile phone calls and text messages can be monitored and diverted by snooping parties. This can happen even before they get to the basestation. The BBC recently demonstrated GSM hacking in an online video.

Once calls and messages are in the mobile backhaul network, in many cases, no encryption is applied at all—not even the broken GSM code. In the past, hackers would have had to buy or by some other means obtain radio equipment identical to that they wanted to take over illegally. This was not an obstacle for those intent on industrial or governmental espionage, but it put it beyond the means of the run-of-the-mill hacker who has become familiar since the mid-1990s. Even if the hacking was not beyond the average hacker’s technical capabilities, it was beyond his economic capabilities. Now commercially available microwave monitoring equipment can be employed to pick out communications channels, to listen and record all conversation and ambient noises for up to 72 hours. One research firm also demonstrated how cell towers can be spoofed to intercept communications.

Secure Management

Another aspect of microwave security encompasses how secure is the management of the network. Even if the payload of a microwave backhaul network is secure, the management may not be, allowing hackers or others with malevolent motives to drop or kill traffic. Unsecure management channels can allow them to create mismatched frequency settings between radio pairs, reconfigure circuitry or reroute payload traffic to another radio if a cross-connect is present. For example, there was an instance where unauthorized users took control of a motorized antenna and repeatedly sent instructions for the motor to adjust the position of the antenna, eventually draining the batteries for the entire site, rendering it “dead.” However, with the shift to the all IP/Ethernet network of the future, hackers are finding ways to wreak havoc on backhaul networks from their desktop PCs, smartphones and other powerful mobile computing devices.

Access Control

Access control of the microwave network is also a cause for concern. It is critical that only authorized personnel are allowed to log onto the administration of a microwave backhaul network. Like many computer-based systems, microwave radios are set up with some basic logon access procedures. Oftentimes, the logon screen will not look very dissimilar from the typical Windows or Macintosh workstation. There will be a dialog box for a username and a password. However, unlike the typical desktop computer, a microwave radio’s graphical user interface is not logged onto that much. Therefore, as per human nature, their usernames and passwords become all too predictable. “Root” and “admin” and “123456” and “password” were very popular as usernames and passwords, respectively, according to one security study. A “mechanized” or “dictionary” attack can randomly generate username-and-password combinations and succeed in unlawfully logging onto a radio on this premise: that the logon will be subject to people being creatures of habit. Thus, there must be a way for microwave network administration to enforce a hard-to-guess username/password security policy.

Another aspect to access control is the issue of the level of control. It is also essential to control what each legitimate user is allowed to perform once logged in—to prevent voluntary and involuntary damaging actions. Not only must users be limited to their area of responsibility and knowledge and avoid involuntary commands that could damage the network but also reserve critical activity for designated key personnel (e.g., cryptography officers).

Would my Radio Network be Secure?

Given the security issues around microwave payload, management and access control, many questions have been raised. Would my microwave radio network be safe from intrusion? What would be the impact of breached calls or text messages? There could always be potential for a Greece type of incident. More importantly, the proactive questions to ask about microwave network security include:

  • Who does need a high level of security?
  • What comprises the high level of security necessary to protect my microwave backhaul?
  • What precautions will a high level of security invoke to protect my network?
  • How is this high level of security implemented?
  • What are the options for high-level security?
  • How do I get a high level of security for my network?
  • Is this high-level security solution standards-based?
  • What type of threats does my high-level security solution need to protect against?

We’ll examine these questions more in future posts. Or see our white paper.

LTE Capacity Shortfall: Why Small Cell Backhaul is the Answer?

With exploding demand for mobile broadband services, networks must evolve to meet expanding capacity and coverage demands. Small cells are emerging as a viable technology. This paper reviews how backhaul for small cells will need to adjust to meet the specific challenges for small cell deployment.

Refarming UHF Spectrum: Wireless Opportunities & Challenges for 4G

With more countries starting the auction process, the U.K. announced its intention in April, to sell off recently vacated prime 800MHz spectrum, seen by many as vital for rural wireless broadband expansion. This is happening as a consequence of the switchover from analog to digital broadcasting technology. In many countries this has already happened and globally is expected to be completed before the end of the decade. With the change in technology, broadcasters have the ability to transmit a greater number of channels, thus satisfying public demand, while using less spectrum. It is this development that is making spectrum available and is referred to in some regions as the “Digital Dividend.”

UHF spectrum, 700MHz to 900MHz, is attractive to many users because it covers what is known as the “sweet spot” for radio transmission. This sweet spot is where the ideal balance between range, bandwidth and cost resides. It is for this reason that this particular spectrum is so attractive to many users. The main competing demands for this spectrum are from broadcasters wishing to deliver HDTV using the DVB-T2 protocol (or similar) and cellular network operators looking to deploy LTE. There are however other interesting proposals such as white space usage.

Importantly, it is not just the competing interests for this spectrum that need to be considered, but also the effect of these new services on the many millions of pieces of existing equipment that are out there in the market place that users will expect to be able to be used for some years to come. These factors are explored in greater detail in a recent white paper from Aviat Networks that covers both the technical and organizational issues raised by this process and how they have been tackled in a number of major markets around the globe

Ian Marshall

Regulatory Manager, Aviat Networks

The World’s Longest All-IP Microwave Link

Successfully Implementing a 193-km Microwave Link over Water to Deliver 99.9995 Percent Availability


For most designers of microwave transmission paths, engineering a reliable link over water can be a daunting task. Reflections off the water surface can play havoc with the received signal, leading to high levels of interference resulting in fading and ultimately a high level of errors and signal interruptions. For these types of paths, performance calculations using commercially available software planning tools will be insufficient to ensure superior path performance. In these cases, experience and understanding of the key parameters that influence microwave performance are critical.

Recently, Aviat Networks and our agent, Telecomunicaciones y Sistemas S.A. (TELSSA), deployed an Eclipse microwave link for Central American Corporation for Air Navigation Services (COCESNA) in Honduras that crosses over 193 km, most of which is over water. With careful design and installation, this link is now operating successfully.

COCESNA is responsible for the air traffic control over Central America territory and oceanic areas, therefore, availability of service is a critical issue. Continue reading