Stadium WLAN Design Considerations

To start off, what is a WLAN? It stands for Wireless Local Area Network, it is a type of network that connects two or more computer instruments and/or devices wirelessly. This allows devices to communicate with each other in a close geographical area. Networks can be as large as a campus or as small as a room. This makes the network more accessible for devices by reducing most of the wired connections.

Equipment Required

Building a WLAN network requires a certain set of components to enable. Products such as access points and directional antennas. First, Access Points also known as an AP, is a piece of equipment that enables a wireless connection to a wired network. AP’s are generally connected to a router also known as a default gateway, and inside most routers today are switches, allowing the network to communicate with the public network. This allows the network to access the internet. AP’s are versatile pieces of equipment that can establish a new network or expand an existing network; AP’s operate on 2.4 or 5 GHz bands and can support multiple users.

A directional antenna concentrates the signal in a specific direction rather than having it radiate everywhere. Some antennas are built inside access points, these antennas transmit the signal in all directions. In most cases, these are not suited for a venue like a stadium due to RF pollution. This results in degrading service. Directional antenna’s help to minimize negative effects such as RF pollution.

Selecting the Right Equipment

When determining what equipment to purchase there are some considerations that will dictate what products are required. The first consideration is the total capacity of the stadium. One should plan to have a network that can support the capacity and then add some additional as there will be some users that connect multiple devices to the network. When dealing with large amounts of people at a venue, there should be an AP count. When doing an AP count for a stadium that holds 50,000 people, assume a standard AP can support up to a max of 250 users. That would mean for the stadium of 50,000, there would be a need for 200 APs. This would be at the max user limit for the AP under the consideration that everyone connects one device. Trying to maintain that amount of people on it even for a short period of time will drastically shorten its life expectancy causing it to fail and break down. Under the assumption that an optimal percentage is around 60% of the APs standard limit. That would mean each AP can support 250 users, with 60% capacity there would ideally only be capacity for 150 users on it. This will help maintain the longevity of the AP as well as keep its operation service efficient and effective. Instead of installing 200AP’s, there should be 334 APs set up inside the stadium.

Location is Key

Next is the placement of AP’s, the first step is determining where the highest user density is in the stadium. This can be discovered by doing a survey of the stadium. Once the high-density locations are found, additional AP’s in these areas should be allocated to handle the workload. AP’s should also be located where the signal drops to provide full coverage. Knowing how much power is being emitted and dissipated will help determine the WLAN’s quality. If the power being released is too low, then the user will not get the greatest of service and in some cases, they will be unable to connect to the network.

Another factor that will also help increase the quality of service is how much bandwidth is needed to sustain all the users. The WLAN should have enough bandwidth to support the consumer’s needs so that they are able to surf the internet with enough throughput speeds, making calls and texts without delay.

Directional antennas can also help increase throughput speeds and increase power. As discussed earlier this will help reduce RF pollution, which will minimize interference. Interference such as co-channel interference, is when two or more AP’s are transmitting at the same frequency channel. After doing the survey on where to put the AP’s, the next thing is to do a coverage prediction. This helps to guide the placement of directional antennas. One of the best ways to conduct a coverage prediction is to get a RF coverage predicting tool. It will help to determine the signal strength and what the SNR levels are going to be like in the stadium, what the AP’s radiation pattern will be if it were placed in that part of the stadium, and several other factors. These are some of the crucial parameters one needs to look at in order to point the antenna in the correct location.

After doing a coverage prediction survey for the stadium, the next step is selecting the equipment. Equipment should follow IEEE standards for WLAN which consists of 802.11, 802.11a/b/g/n/ac/ax. Remember there are a lot of vendors out there that sell those pieces of equipment, having their own advantages over one another. Make sure to do some research as to which piece of equipment best fits the needs. One crucial aspect to look at in these pieces of equipment is the security features. Since people are going to use this WLAN not only for surfing the internet and using social media applications. The stadium is also going to use the network for its internal office use, including credit card transactions, so security is imperative. One way to help keep one’s network secure is to purchase AP’s with security features built in. The main features fall under these IEEE standards like WPA, WPA2 with AES and 802.1x etc. These security features will create encryptions for one’s network and help protect the network against cyber-attacks.

The last step is installing the AP’s in the locations determined by the survey. Though there is one more thing to consider when placing the AP’s. The final placement should not only be in areas that are functional but also in areas that are aesthetically pleasing. Generally, this would mean keeping them out of people’s sight and path. This could affect the way one’s stadium looks and can potentially cause more harm than good.

For any questions additional questions beyond the materials covered in this article please feel free to reach out to Scientel Solutions directly to assist with all your wireless and integration needs by filling out the form under Contact Us.


Scientel Internship Experience

Lab Room

Internships are a key part in developing a well-rounded resume and in building experience while in college. Internships, additionally, shape and develop your professional character; without my internship at Scientel, I would not be the same person that I am in the workplace today.

The Scientel Internship challenged me in unique ways that are not possible in a classroom setting. I was challenged day in and day out on with issues in networking, security, information technology, and hardware. These challenges required me to work outside of my comfort-zone and research topic’s that I had never worked on before. This allowed me to get a feel for multiple sides of my field. I gained experience and knowledge that was irreplaceable. I was challenged in ways unlike any that are faced in the classroom, I was hands-on with equipment, troubleshooting unique problems.

One of the major things I learned during my internship, through experience, is that explaining the theory of how something works does not equate to having the practical knowledge to perform those tasks. Hands on experience with equipment problem solving is essential in developing your skills and knowledge. Nothing ever works exactly how its supposed to and no problem is ever the same, it is essential to have experience troubleshooting on equipment to a variety of different scenarios.

Lessons Learned

An important lesson is that when you get stuck with a difficult problem to not give up and immediately and find someone to help you solve the situation, sometimes there may not be someone with the answer. I learned that doing your own research and troubleshooting brings you the best long-term benefit. This does not mean you cannot ask for help but if you do not take the time to try and learn it yourself you will miss fundamental skills like problem-solving.

The experience from being able to work hands-on with equipment used in the industry is a huge advantage when entering the workplace. Many graduates have little to no practical experience upon graduation, this makes an internship extremely valuable. An internship experience is what makes an individual stand out from other graduates every year. Another benefit of having the internship was getting to experience multiple sides of the industry. I was able to experience the technical side, business side, and even the skilled labor that is required when moving and installing equipment.

In Conclusion

Being able to experience every part of the process helps make me more knowledgeable in my field and more confident in a variety of situations. I enjoyed being challenged while developing skills and experience during the duration of my Scientel internship and would recommend to anyone that is trying to get ahead in this field to consider seeking an internship.

The Importance of Change Management

CollaborationPicture this……  You run several large Managed Services contracts.  Your Network Operations Center (NOC) is responsible for monitoring and supporting first responder networks all across the country.  Of course, with a first responder network, lives are at stake and these networks cannot be down.  You have been involved from the beginning to ensure that there is redundancy to safeguard against exactly that.  It is now 2:00 a.m. because, of course, it is.  Network alarms seem to only happen overnight.  Your phone is blowing up with text messages, most from network devices and a few from the NOC technicians monitoring these networks.  The alerts and techs are warning of a substantial outage in one of those networks.

All backup devices are up and operating but your focus needs to be the primary devices.  You hop on the phone and start talking to the NOC techs.  They have done all the basic troubleshooting and cannot seem to reach the imperiled devices.  They are asking for approval to escalate internally to the engineering staff, while they contact the on-call customer to get a status and let them know of their issue.  Nobody is answering at the customer location.  You assume it is due to the fact the customer’s primary network is done.  Your engineers are also stumped as they cannot get to any of the devices either.  Even the backdoor interfaces you have installed and configured.

As you are the 3rd level of escalation, it is your responsibility to notify your management counterpart at the customer location.  Just as you are about to make that call, your first level NOC tech calls.  He is in contact with the customer and has just been made aware that they are doing scheduled maintenance.  Starting to feel relieved that there is no catastrophic issue going on there, you think about going back to sleep.  You look up at the clock and realize this whole exercise has taken 2 hours and it is almost time to get up for the day.  You make the coffee and begin to post-mortem.

With proper Change Management Processes

It’s 2:00 p.m. and you are heading into a customer’s Change Management meeting.  You attend this meeting via phone, once a month.  In this meeting, you discuss events that are planned regarding maintenance on the devices within that network.  Your customer announces that network-wide maintenance will occur on the regular 3rd Thursday of the month.  You note it for later reference.  The meeting goes as planned and you begin to prepare a Change Notification for your NOC staff to read and file in preparation for the outage.  The day of the actual work arrives.  Your NOC techs, by design, have switched off the monitoring tool for those specific devices that we know will be affected.  At the allotted time, the primary network is taken out of service.  Your NOC team knows this as they see the secondary devices begin to carry the network traffic.  The customer network team notifies you when they are completed and your team watches as the network nodes all return to green.  Your team then goes in and re-activates all the alarming.  Everything goes as planned and the network is back up and running on its primary devices.

So, what have we learned here?  If you want a good nights sleep and not to be making a pot of coffee at 3 a.m. preparing to tell a customer his primary network is down, create, participate and exchange information prior to any network work.  It is called Effective Change Management and it can make your life a whole lot more bearable.  Not to mention, a better night’s sleep.

What are botnets? How do they work?

Lines of Code

Over the last few years, malicious code, normally known as Malware has been around in some form or the other. Hackers have been breaking into computers over the Internet to leak sensitive information. The world has now been introduced to the concept of Botnets which have caused several security issues.

What exactly are Botnets?

Botnets are a group of computers which are infected with malware to take control of any device connected to the internet. They are like worms. They can be a combination of devices running different operating systems. Devices like cheap webcams, video recorders have little security settings. The hackers find it easy to take over such devices in no time and build huge botnets.

What are Botnets used for?

Botnets are commonly used in DDoS (Distributed Denial of Service) attacks. With the collective computing power from the infected systems, the botnets are highly capable of stealing sensitive information, malware propagation, disruption of the internet, sending spam and spying on individuals or organizations. Cyber criminals or Botmasters as they are called do not build these botnets only to compromise an individual computer. These are designed to infect millions of devices and bring a large network down. There are botnets that can self-propagate, find and infect devices automatically. They are constantly searching for vulnerable internet-connected devices that are lacking the operating system updates or antivirus and security settings.

They are used to commit click fraud. This is nothing but a scheme to fool the advertisers into thinking that people are clicking on their advertisement. Botnets spread due to downloading attachment links. Malicious software can be attached with illegal software or media downloads. When a user clicks on this link of the infected site, the botnet software gets downloaded and gets installed on the user system. Botnets can send spam messages to a million devices in a short period of time. Botnets destroy a large amount of data in the host system. Smart botnets have the capability of going offline for a period and come back again when the targets are not suspecting.

Botnet Attacks

Mirai botnet

The Mirai botnet was responsible for bringing down a large amount of internet traffic and has been said to be the largest of its kind in history. The servers of the company that controls the internets DNS infrastructure were affected by this botnet. It brought down critical sites including Twitter, Netflix, CNN and many others in the US and Europe. The internet outage was caused due to a DDoS attack. Unlike the other botnets that have been built to date by infecting many computer devices, this was largely made up of internet of things (IoT) devices like digital cameras and DVD players. The Mirai botnet mainly targeted these devices with weak or default passwords. Akamai has reported that Mirai is still around with two DDoS attacks of more than 100 Gbps.


A new botnet has now been discovered called Reaper which is said to be infecting the IoT devices at a much faster pace than Mirai did. This botnet has the capability to bring the entire internet down. Reaper has been known to affect D-link, Netgear, and Linksys.


Botnet detection is not an easy task as these have the capability of being dormant for a while and come back when the botmaster programs them to. Botnets try to disguise their origins. In most cases, the owners do not know that their systems have been infected and have become a part of a botnet.

The easiest way a user can find if his computer system has been affected is by using an anti-malware product. Also, the user can look at the processes that are running, the programs that are installed. These might reveal the presence of a botnet infection. But in most of the case, the detection is not so simple.



As we all know Prevention is better than Cure, the users can prevent their systems from getting infected by following some steps. These can be implemented at an individual user level and at a network level as well.

Individual level:

  • Install anti-virus/ anti-spam software and keep them updated regularly.
  • Turn ON the Firewall settings and restrict unwanted access.
  • Make sure that the OS is updated from time to time.
  • Do not download illegal stuff like pirated music, games, files etc from the internet.
  • Do not click on attachments or links from unknown email messages.


Network Level:

  • Have Firewall, IDS/IPS systems, and content filtering in place.
  • Monitoring unusual increase in traffic.
  • Have DDoS protection in place.
  • If individual user systems have been suspected of being botnet infected, try to remove the malware software immediately. If this is not done in time, the other systems in the network might get infected as well.
  • Make sure that all individuals in the company have their systems with the updated software.
  • Monitor firewall logs to identify botnet command and control centers.
  • If any infection has been identified, notify the anti-virus vendors immediately.


Take away points

Running anti-malware software on user systems is the basic way to prevent botnet attacks. The most effective way to fight botnets is to be vigilant and be aware of this threat. Keep your systems updated. Help your coworkers to understand the effects of a botnet attack. Make sure you stay away from clicking on unknown email links and attachments. We need to help everyone realize that if one computer gets infected, it might cause harm to the entire network.

With the increase in the IoT and more and technological advancements, the potential of such botnet attacks and their power also increases. Taking preventive action will protect us, our company network, our identity, devices, and data.





Basics of Troubleshooting – What you need to know before you ask

In any given profession there will always be a time where something goes wrong, some tool malfunction, or something that you’ve used every day seems to act differently. In today’s world, most of the time the problem is computer related. We’ve come to depend on these devices and their functionalities, whether it’s a laptop, cellphone, or server service.  It often causes frustration and loss of productivity when they fail.

What to do when everything goes wrong?

When this happens what’s the first thing you do? Call IT? Call a friend? Throw it away? This is the first step to really learning and understanding the tools we use every day. What do we do when it goes wrong? In most cases the best thing to do is the good ol’ standby…reboot. If it’s electronic and has an operating system running on it there’s a good chance that forcing a reboot will help the issue. If not, then you need to look further.

Determine the issue

Since the reboot did not work, think about the issue being experienced. Is it application related – does another program/app work? Is it network related – does the device itself work but you can’t access the web or any of your services? Is it hardware related – does the device seem “stuck”? Is it working but you can’t launch any applications? Drilling down into the issue and determining what’s happening rather than just that something happened is key. Once you have narrowed down the issue to one of the general buckets (application/network/hardware/operating system) it will allow you to move onto the next phase of the troubleshooting process.


The next step would be to try to use a search engine to try to troubleshoot, if available. There is a wealth of knowledge on the web and most likely the issue you are facing will have been documented already. The trick to troubleshooting on the web is to describe the issue accurately. For example, if you have an error message on your computer with an error number. Don’t just search for the error number, rather search for the entire message that’s displayed as well as the name of the application you were trying to use and the operating system running. It seems like a lot to type into a search bar but the more you have describing the issue, the more likely you are to find exactly what you are looking for in the first page of results.

After all of this you may still have the issue and need to call into IT or someone else knowledgeable on the equipment. It is very important that you articulate to that individual what is happening just as you described in the search online. The more information you have up front, the better your chances are to get resolution from the technical representative you are working with. Make sure to describe what you were doing when the problem occurred, or what you were attempting to do, and what happened. However, please try not to get too upset when they ask you to reboot.

Wi-Fi Standards: Past, Present and Future – What They Mean to You

Back of Wi-Fi Router“Wi-Fi” is now such a commonly used term, people don’t give it much thought, other than knowing they can get their Internet through wireless. Across America in homes,  airports and coffee shops, people are looking to connect their laptops, tablets, phones and other devices to the nearest wi-fi network.  But what is “Wi-Fi”, and where is it going in the future?

Wi-Fi has its origins in a 1985 ruling by the FCC, that released the ISM Band (2.4 & 5 GHz)  for unlicensed use.  Beginning in 1997, the IEEE (Institute of Electrical and Electronics Engineers) developed a wireless standard known as 802.11 by which data can be communicated over a wireless link.  Since that time, there have been a number of amendments to this standard, each with increasing speeds and improved coverage capabilities.

The earliest standards were 802.11a and 802.11b, running at frequencies of 5 GHz and 2.4 GHz respectively.  By year 2000, the 802.11b was most common, with peak throughput bandwidth of 11 Mbps. In 2003, the 802.11g standard was developed that increased bandwidth speeds to a peak 54 Mbps.

Forward on to 2009 was the advent of 802.11n, a dual-band standard that runs at both 2.4 and 5 GHz.  This time the peak bandwidth speeds increased to 600 Mbps. Jump to 2014, then 802.11ac hit the market with potential speeds up to 3 Gbps. The introduction of the “ac” standard was the first time the “MIMO” antenna technology was used – Multiple In, Multiple Out.  This multiplies capacity of the radios by transmitting different signals over multiple antennas. An addition to the “ac” standard is called   “Wave 2”, which introduces a modulation method known as OFDM (Orthogonal Frequency Division Multiplexing).  OFDM converts 1 high-speed data channel into multiple parallel lower-speed channels.  This results in better coverage and longer-distance reception. As this article is written in the beginning of 2018, this is the wi-fi standard of today.

What does the future hold?

Behold the newest commercial  wi-fi standard, 802.11ax. What is so special about “ax”?

The new 802.11ax dual-band standard is designed to improve spectral efficiency, especially in dense deployment areas. The most notable thing about “ax” is the dramatic jump in speed, at up to 4X the rate of “ac”, for a peak bandwidth of 10.5 Gbps. So ax has two major things going for it – better coverage in dense wi-fi areas, and much higher speeds.  The “ax” wi-fi gear will be publicly available on the market in early 2019.


Other Interesting Future Wi-Fi Standards

What about all this talk of Internet of Things (IoT)? How do you connect refrigerators, thermostats, dishwashers, and a host of other devices to the network?  Say hello to 802.11ah.  This is known as Wi-Fi HaLow.  It runs in the 900 MHz frequency for easy penetration through walls. It has lower power consumption and wider range than standard wi-fi, designed to connect to IoT devices. It is also used for Smart Meters, M2M (machine-to-machine) and rural communications.

Want to have the latest Home Theater setup?  Give 802.11ad a try. This standard is extremely high frequency millimeter-wave, running at 60 GHz.  With bandwidth throughput of 7 Gbps, it is designed to provide wireless audio and video streaming for home theatre systems, office devices, displays, and other uses.  It only goes short distances and will not penetrate through walls.  But 802.11ad is positioned to play a big role in home theatre systems in the future.

Of course there are other wireless standards on the roadmap for the future, including 802.11az running at 60 GHz to be introduced in 2021.

With every passing year the speeds keep getting faster and the coverage capabilities better.  Do you have an idea of what you want in your future wi-fi? Submit your ideas to the IEEE, as they are interested in hearing them.