For my presentation I will talk about ac. I will discuss the wave 1 and wave 2 standard adoption process. Specifications and configuration

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1 For my presentation I will talk about ac. I will discuss the wave 1 and wave 2 standard adoption process. Specifications and configuration options of each wave will be provided. Finally I will share the applications of the new802.11ac standard. Growing Wireless demand Number of devices High bandwidth Services Standard Adoption Process IEEE Wifi Aliance Wave 1 Wave 2 Specifications Wave 1 Increased Spatial Streams Wave 2 MU-MIMO Transmist BeamForming Frame Aggregation (A-MSDU and A-MPDU) ac, however, adds an interesting new take on aggregation: all frames transmitted use the aggregate MPDU (A-MPDU) format. Even a single frame transmitted in one shot is transmitted as an aggregate frame. Moving to an all-aggregate, all-the-time transmission model means that the ac MAC must take over all the framing responsibility, and the physical layer works only with the total length of what it transports. Applications Future Demands Upgraded Wired Infrastructure Higher Bandwidth Demands

2 802.11ac Christopher Fletcher CSIT Spring 2016 In 2007, the n draft standard was being finalized. Members of the working group began working on the Next big thing which they called VHT for Very High Throughput. The technology standards produced from those studies would become the key components of ac.

3 Very High Throughput Source: Aruba Networks: Very High-Density ac Networks Planning Guide While the initial goal was Very High Throughput, today network architects are not simply planning for high throughput in larger conference halls like this one, but having the to support higher device density.

4 The announcement of Pope Benedict in 2005 Source: NBC News You see, planners didn t have to worry about a large number of devices because in 2007 most us used flip phones and a stand alone digital cameras. Coincidentally, while the new wireless standard was being developed another technology was growing rapidly. Two photos showing the announcement of Pope Benedict in 2005

5 The announcement of Pope Francis in 2013 Source: NBC News and Pope Francis in 2013 contrasts the ownership of mobile devices such as smart phones and tablets.

Wi-Fi Certified Devices by Category - 2000-2012 Source: Wi-Fi Alliance You see, in 2003 there were less than 500 Wi-Fi certified devices.

6 Wi-Fi Certified Devices by Category Source: Wi-Fi Alliance You see, in 2003 there were less than 500 Wi-Fi certified devices. Almost of all of them were networking equipment and computers. In 2006 we start to see mobile headsets or smartphones, and by 2012 there are almost 1000 certified smartphones on the market.

Very High Density Source: Aruba Networks: Very High-Density 802.11ac Networks Planning Guide So we will see that the 80211.

7 Very High Density Source: Aruba Networks: Very High-Density ac Networks Planning Guide So we will see that the ac standard provides for very high throughput, we will also see applications to support very high density in offices, conference rooms and

8 Levi s Stadium Santa Clara, California Source: even football stadiums. This is Levi s Stadium in Santa Clara, California. Later in the presentation I will discuss how ac was deployed to provide provide what many sports organizations market as a richer fan experience.

9 Demands and Goals Source: Wi-Fi Alliance As the prevalence and features of wi-fi devices grew, the demands on manufactures of access points grew. The demands for higher data rates, growing capacity and improved reliability was being driven by more device types and devices per person. Mobility of devices demand that wi-fi be available in more locations and provide adequate access to higher bandwidth traffic.

Legacy Compatibility Necessary Source: Wi-Fi Alliance These new demands required new and improved standards to be developed, but the standards for security, along with interoperability and

10 Legacy Compatibility Necessary Source: Wi-Fi Alliance These new demands required new and improved standards to be developed, but the standards for security, along with interoperability and compatibility of legacy Wi-Fi devices had to be taken into consideration. An entirely new system requiring the replacement of all access points and devices would not be an acceptable solution.

802.11ac Standards Timeline Source: O Reilly Media In May of 2007, the 802.11 working group started the Very High Throughput study group.

11 802.11ac Standards Timeline Source: O Reilly Media In May of 2007, the working group started the Very High Throughput study group. The purpose of this group was to provide the IEEE with a Project Allocation Request. The group split into two separate projects. One which would work to develop new 60GHz frequencie and 4GHz channel, which would become the ad standard. The second group would develop standards below 6GHz. It was decided early in the project to focus on the 5Ghz frequency bands used in n. The Project Allocation Request was approved by the IEEE in September of In June of 2011 the first draft had been agreed upon. At roughly the same time, the Wi-Fil Alliance, a group that certifies that manufacturers followed set standards, began developing technical groups for the certification of new network and user devices.

Production Timeline Source: Cisco In 2012 802.11 devices we're being developed based on the draft standards.

12 Production Timeline Source: Cisco In devices we're being developed based on the draft standards. In the summer of 2013, the first enterprise Wave 1 devices were released and soon after the Wi-Fi Alliance began certifying Wave 1 devices. In December of 2013, the IEEE approved and published the ac standard. Beginning in the summer of 2015, ac Wave 2 devices were released.

13 Specifications Wider/Additional Channels Beamforming Up to 8 Spatial Streams Multi-User MIMO or MU-MIMO There were many improvements made from the n standard to create the new ac standard. These are the core changes are the specifications I will be talking about today.

14 Mandatory Features Source: Wi-Fi Alliance The AC Standard had some mandatory features and some optional features some mandatory features I won t talk about are support for Clear Channel Assessment (CCA), Clear To Send( CTS) Indication.

15 Optional Features Source: Wi-Fi Alliance These are the specifications that are options. For this reason, it is critical that users check the specifications of devices they purchase as these options have the greatest impact on performance.

Why More Channels Is Important Source: As we have learned this spring, transmission media needs to be clear of other transmissions in order to avoid collisions.

16 Why More Channels Is Important Source: As we have learned this spring, transmission media needs to be clear of other transmissions in order to avoid collisions. In the wireless environment, each channel could be considered a separate medium. In n we chose channels 1,6 and 11 to avoid interference, but radios had to be placed so close to each other that inference was inevitable. The ac standard brought us twenty five 20MHz Channels.

Channel Plan with 11 Channels in 5Ghz with Minimum Separation of Two Cells Source: With so many available channels, the chance of interference with other access points is much

17 Channel Plan with 11 Channels in 5Ghz with Minimum Separation of Two Cells Source: With so many available channels, the chance of interference with other access points is much less than with n. This expansion of channels also makes it possible to place more radios in a single locations, thus supporting the high density of devices that we see today.

Available Channels Source: Aruba In the 802.11ac standard, by combining channels, you could accomplish very large channels with the potential to provide high throughput.

18 Available Channels Source: Aruba In the ac standard, by combining channels, you could accomplish very large channels with the potential to provide high throughput. It also provides the possibility that you could configure two channels to act as one larger channel. Within the range of channels are Dynamic Frequency Channels also known as DFS, which listens for interference and can automatically adjust for to avoid broadcasting on the same channel as another device. Also within the 5GHz spectrum is United States weather radar so these frequencies are disabled by default on many access points.

Channels Speed Improvements Source: O Reilly Media This chart compares the relative speeds to different size channels. There are a few things I want to point out in the right column.

19 Channels Speed Improvements Source: O Reilly Media This chart compares the relative speeds to different size channels. There are a few things I want to point out in the right column. If you look compare the 20MHz channel in n vs ac, they provide the same level of throughput. We will obviously see other features of ac that provide a greater capacity. But if we go down that right column, we see that the capacity a little more than double every time we double the channel frequency. Thus by the time we get to 160MHz channels, we find they have 9 times as much capacity as 20MHz channels.

MU-MIMO Using a Combination of Beamforming and Null Steering to Multiple Clients in Parallel Source: Cisco Next I want to talk about Beamforming.

20 MU-MIMO Using a Combination of Beamforming and Null Steering to Multiple Clients in Parallel Source: Cisco Next I want to talk about Beamforming. This is the practice of focusing energy from an array of antennas to a best communicate with the client. In this example, each color loop is primarily focused on the corresponding user. The second component is that the signal is minimized in the direction of the other users.

Null Steering Source: oreilly.com This is performed by an algorithm and a process called Null Steering. In this example we have the steering matrix Q and the signal we want to transmit on matrix H.

21 Null Steering Source: oreilly.com This is performed by an algorithm and a process called Null Steering. In this example we have the steering matrix Q and the signal we want to transmit on matrix H. These matrixes are combined to direct the appropriate signal to the proper device. This calculation also works to prevent the wrong signal from going to the wrong device. In this case, the blue and red signal have null signals on H-Green, thus minimizing any interference to that device.

22 Spatial Streams Source: Aruba In ac there is the potential to have up to 8 spatial streams between two devices. Unfortunately, the devices we see now only have up to four spatial streams. A spatial stream is a wireless signal from one device to another. The theory is that with multiple streams, each radio signal may be able strengthen the amplitude of the overall signal.

23 MU-MIMO Source: Aruba Next let s look a Multi-User MIMO. First let s discuss MIMO which stands for multiple in, multiple out. This allows multiple antennas to be used to communicate with devices with multiple antennas. The advantage of MU-MIMO is that for the first time in AC wave 2, access points can now transmit to multiple devices at one time. In this example we have an access point with 8 antennas and four devices.

24 MU-MIMO Transmission Source: Aruba This chart the shows the sending and receiving in a multi-user MIMO environment as shown in the previous diagram. If we look at the left green column, we see multiple frames being sent to stations A,B,C and D. Frame A is larger as it had 4 spatial streams. Devices B,C and D are sent smaller frames. Then you see stations A,B and C send acknowledgments to the AP, and then device A sends a frame back to the AP. As we proceed down the timeline we see the AP sending to multiple devices an a single window, then receiving from a single device in a client window. Even thought MU-MIMO is used for transmission only, it doubles the efficiency over n.

Physical and MAC Changes The Physical level frame standardized MAC Frame Sizing A-MPDU Source: O Reilly Media Because of the complexity of this topic, I wanted to mention the changes to the physical

25 Physical and MAC Changes The Physical level frame standardized MAC Frame Sizing A-MPDU Source: O Reilly Media Because of the complexity of this topic, I wanted to mention the changes to the physical and mac layer. The frames at the Physical layer are much simpler than the n standard because the frame formats were standardized to one format. In the MAC layer, there were two major changes, first the maximum frame size was increased from 8000 bytes to over 11,000 bytes. The second change was that the MAC layer would use Aggregate MAC Protocol Data Unit also know as A-MPDU. The purpose of the aggregate MPDU is to limit the overhead to package and send a frame. It also requires the device to look ahead in the transmit queue and package subframes to the same devce into a single A-MPDU. The photo includes sample A-MPDU Frame.

Throughput Comparison Source: Aruba As you have seen the core changes, now how do these changes impact the capacity of 802.11ac over the previous standard 802.11n.

26 Throughput Comparison Source: Aruba As you have seen the core changes, now how do these changes impact the capacity of ac over the previous standard n. The 80 MHz channels will improve capacity 2.1 times compared to the N Standard. By increasing our spatial steams from 2 to 4 streams, we also double our throughput. By moving form 64-QAM 5/6 in n to 256-QAM 5/6 we see a one hundred thirty three percent improvement. Both Beamforming and multi-user downlink MIMO will double the capacity of the original throughput. Add all of these features together and you get a potential ten to tenty times improvement of n.

27 Applications Source: O Reilly Media What are some applications that you might see take advantage of this wireless technology? Well the obvious every day applications we use will be much more efficient. Now new technologies that once didn t have the capacity to perform will now have adequate bandwidth. Any thing using HD video, whether it is for entertainment, news or law enforcement with improve dramatically. We can also consider utilizing a mesh network in a high bandwidth environment or in places where it is difficult to run ethernet cable such as a warehouse.

Very High Density (VHD) - Best Practices Source: Aruba We started with the creation of a Very High Throughput committee and have really found that some of the standards provide for high throughput,

28 Very High Density (VHD) - Best Practices Source: Aruba We started with the creation of a Very High Throughput committee and have really found that some of the standards provide for high throughput, but the more likely need it high density for a large number of devices. These are the best practices as suggested by Aruba when deploying Wi-Fi to schools, conference rooms and yes, football stadiums.

29 802.11ac / VHT Application - Levi s Stadium 70 miles of cable to support Wi-Fi 400 miles total cabling 1, ac access points 600 AP s support the 45,000-seat lower bowl 1 AP for every 100 seats within the bowl Levi s Stadium became the first stadium to carry 40 Gbps of Internet capacity During the 49ers-Broncos preseason game in 2014, there were 20,000 concurrent Wi-Fi devices connected Source: If we want to look at the application of ac in a Very High Throughput environment with high device density, then we need to return to Levi s Stadium. Opened in July of 2014, it was presented as the most connected, most modern stadium in the country. There were many games hosted in the fall of 2014, but the best test case was It was built with over 1, ac access points, 70 miles of cabling dedicated to wireless and a 40Gbps internet connection.

30 Source: GeekWire On February 7, 2016, Levi s stadium hosted Super Bowl 50. From 6 a.m to 11 p.m. fans and media used 10.1 terabytes of data on Levi s Stadium Wi-Fi network. There were 27,316 unique WiFi users during the game and a peak of 20,300 simultaneous users shortly after kickoff.

31 Conclusion In conclusion, the Very High Throughput team succeeded in in developing a standard that allows for a wireless bandwidth that is hard to imagine and yet to be seen. In doing so, they have created a platform that meets a much greater need today which is very high device density. Efficiencies created by increasing available channels, standardizing beamforming and adding multi-user MIMO attribute to the many dynamic applications of ac.

32 References Soper, Taylor. "Super Bowl Fans Use a Record 10TB of Data on Levi's Stadium WiFi Network, up 63% from GeekWire." GeekWire. GeekWire, 09 Feb Web. 30 Apr "Instagram Photo by TODAY Mar 14, 2013 at 4:11pm UTC." Instagram. Trans. NBC. NBC News, 14 Mar Web. 30 Apr "Levi's Stadium - Home of the San Francisco 49ers." Levis Stadium Levis Stadium Comments. Levi's, n.d. Web. 30 Apr < Wi-Fi Alliance. "Significant Performance Advancements for the World s Most Loved Technology." Wi-Fi CERTIFIEDTM Ac (2013): n. pag. Web. 29 Apr Gast, Mathew S. "802.11ac: A Survival Guide." ac: A Survival Guide. O'Reilly, n.d. Web. 29 Apr < Cisco. "802.11ac: The Fifth Generation of Wi-Fi." (2014): n. pag. Web. 29 Apr For additional information, here are references for the charts, photos and information that I used in developing this presentation.

802.11ac FREQUENTLY ASKED QUESTIONS. May 2012

802.11ac FREQUENTLY ASKED QUESTIONS May 2012 Table of Contents General Questions:... 3 1. What is 802.11ac?... 3 2. When will 802.11ac be ratified into a standard?... 3 5. Will 802.11ac come out before