Questions and Answers from our Dec. 17 Webinar on 802.11ac

Share Post

We had an excellent webinar, "802.11ac is here. And it's better than you think" on December 17th with guests from Forrester Research Inc. and Yale University. Our guest on our discussion panel were:

  • Chris Voce, Principal Analyst, Forrester Research, Inc.
  • David Galassi, Director of ITS Network Services, Yale University
  • Dorothy Stanley, Head of Standards Strategy, Aruba Networks

If you missed the webinar, you can click here and watch the recorded session on-demand or download the presentation slides.

We received more great questions than we had time to cover during the panel so please find your questions answered below.

Are 802.11ac devices shipping and how well are they performing?Yes, they have been shipping since mid 2013 and are performing well. You can go to Aruba's site on 802.11ac to see some performance numbers here.
Is there a list of 802.11ac mobile devices, phones and tablets from multi-vendors?Yes, the best place to find the most accurate information is the Wi-Fi Alliance search tool that allows you to search for 802.11ac certified products by category. The link to access the tool is here. There are currently over 230 products certified for 802.11ac.
Have you heard when Apple iPad and iPhones will have 802.11ac support? What about Android and Samsung devices?No. Apple is very secretive when it comes to new hardware, even with its business partners. I would expect the next hardware revisions to adopt it given that they have moved to 802.11ac across their laptop and desktop product lines and in order to take advantage of the power efficiency as being shown by their Android competitors including Samsung, Motorola and HTC who have adopted 802.11ac already on their smartphone and tablet platforms.
The Wireless Access Point and the device have to support 11ac, right? for instance, let's say my WAP supports 11bgn and my smartphone supports 11ac, then I will not get the 11ac benefits on my device right?If your Access Point (WAP) only supports 802.11bgn then your 802.11ac smartphone will not see any benefit until you upgrade the Access Point. However if you have an 802.11ac AP, you will still get benefits for your legacy 802.11bgn devices. We see around 30% benefit on average and much greater at further distances from the AP.
Can I mix AP-135s (802.11n) and AP-225s (802.11ac) in a single building? We have high-density large auditoriums in our classroom buildings, in addition to staff offices and "average" density rooms.Yes, we are recommending exactly this approach for customers who are not ready (or don't yet have the network demands) to move their entire network to 802.11ac. We recommend in this case deploying the 802.11ac APs in the areas where you have either the highest density or where the application bandwidth requirements are most challenging.
Will upgrading from .11n AP's to .11ac require new POE switches to power them?No. Existing PoE switches can be used with most vendors' 802.11ac APs, Aruba included. If you are upgrading your switches in the future you should ensure they are capable of PoE+ (802.3at) in order to future proof them as this is likely the last generation of Wi-Fi APs that can operate on PoE (802.3af) power. For more information on Aruba's line of Mobility Access Switches, you can learn more here.
Where do you believe we are on the overall adoption curve for 802.11ac?While we are fairly early in the adoption cycle for 802.11ac, we are seeing the transition to 802.11ac happening much faster than the prior transition to 802.11n. I believe this is driven by the explosion of devices and data-hungry applications that employees and students are bringing into the office and campus. We are already seeing some vendors such as Apple implement 802.11ac across their entire desktop and laptop product lines and many smartphones and tablets have already adopted 802.11ac. In fact just taking a single product, the 802.11ac Samsung Galaxy S4 smartphone, it has shipped over 40 Million devices as of October 2013.
As opposed to A, B, G or N how is 802.11ac different and how will the emerging standard be different from that?While 802.11n supported both the 2.4GHz and 5GHz frequency bands, 802.11ac has limited itself to the 5GHz band only. The Wi-Fi Alliance certification for 802.11n supports up to 3 spatial streams with 40MHz channels. 802.11ac builds on top of the 802.11n standard by extending it in the following ways: (a) expanding the channel width up to 160MHz (with 80MHz supported in the current 11ac products); (b) adopting a new 256-QAM encoding method that is 33% more efficient; (c) allowing up to 8 spatial streams (with current 11ac products supporting up to 3 spatial streams); (d) adopting a single type of Explicit Transmit Beamforming; (e) adding Multi User MIMO so that an AP can transmit to more than one client simultaneously (expected to be implemented in the Wave 2 products in 2015-2016).
Will the current AC access points support the fully ratified AC standard when that happens?The IEEE 802.11ac final standard was ratified in December 2013 and it was published on December 18th and is available here. The current 802.11ac Access Points adhere to a subset of the features in the final standard as certified by the Wi-Fi Alliance. The next iteration of Wi-Fi Alliance 802.11ac Wave 2 certification is likely to enter the market in late 2015-2016 and the additional features will require new radio chipsets. The enterprise Access Points utilizing these chipsets will also require additional CPU processing power and uplinks over 1 GigE to support the higher speeds and therefore the current products will not be software upgradable nor will modular APs be able to realize the improved speeds.
Chipmakers have announced the availability of four stream 802.11ac devices.  When does Aruba expect to offer four-stream 802.11ac?This will likely be part of Wave 2. As with other vendors in this space, we expect to see enterprise-class Wave 2 APs in late 2015.
When can we expect 802.11ac Wave 2 certification and products to become available?Late 2015 is when Aruba and most vendors are expecting to have enterprise-grade Wave 2 APs. Note that these will require in excess of 1 gigabit Ethernet to the AP and will require Wave 2 capable clients to take advantage of some fo the new features in Wave2.
During the discussion of the standards process, the speaker did not discuss the multiple stages (WAVES) of the 802.11ac standard.  Why did they break 802.11ac into wave-1 and wave-2?There is an article on our Airheads community here that discusses Wave 1 and Wave 2here that discusses Wave 1 and Wave 2. Like with 802.11n, portions of the standard will be selected for vendor interoperability certification by the Wi-Fi Alliance in multiple phases. This is typically done due to the complexity of the radio chipset designs and CPU power required to implement the features such as additional spatial streams and extensions to MIMO.
After a standard is ratified how long takes for a product with the new standard is in the market?Given how heterogeneous Wi-Fi products are, the product availability is driven more by the Wi-Fi Alliance certification program since this ensures interoperability between the clients and Access Points of multiple vendors. As we have seen with 802.11ac and 802.11n, the products typically are available in two waves where each certification program is built on a growing subset of the features in the full standard. The first wave of 802.11ac products have been available since mid 2013 and now that the 802.11ac standard was ratified in December of this year, we are expecting the second wave of products to start appearing in late 2015 as the chipset manufacturers are still working on the designs and after the chips are available then enterprise infrastructure vendors will implement these into Access Points.
Does 802.11ac affect the number of users who can connect through a single access point, or is it primarily about the throughput for single users?Yes. Since 802.11ac supports higher data rates, clients are able to transmit their data faster and this leaves more air time free to support a higher number of users.
Does 802.11ac increase distance performance?802.11ac increases the data rate at a given range by leveraging explicit transmit beamforming.
What will be the impact of Qualcomm proposing LTE into the 3.5G band onto future of Wi-Fi.With Wi-Fi currently operating in the 2.4GHz and 5GHz bands there is no impact of LTE if it is deployed in the non-interfering 3.5GHz band. Currently LTE/TD-LTE only interferes with the 2.4GHz band where the LTE side lobes can extend beyond their 2.3GHz to cause some interference. Some newer Wi-Fi APs such as the Aruba AP-115 (802.11n) and AP-225 (802.11ac) have cellular interference mitigation features designed to minimize the impact by filtering out the interference.
Can you speak about security in 802.11ac.  Is it primarily what we get with WPA2 or is there more to it?802.11ac leverages the WPA2 Personal and WPA2 Enterprise that were part of the prior 802.11n standard. The new security capability that it introduces is the ability to mitigate 802.11ac rogue devices that cannot be done with an 802.11n Access Point. For more information on this, you can watch our on-demand 802.11ac security webinar that was held December 4th by clicking here.
Do you expect that 802.11ac would be able to support a wireless only infrastructure?Yes. With 802.11ac bringing Gigabit speeds to the wireless connection it is able to deliver the client densities and performance required to enable a wireless office where the switching infrastructure can be rightsized and unneeded ports eliminated. We have a growing number of large offices that are relying on the wireless connection for both their data and VoIP communication to run their businesses and slashing their infrastructure costs.
With BYOD, how do you also address security issues such as PCI and HIPAA compliance?You can use products such as Aruba Networks' ClearPass to differentiate access for all users carrying personal devices (BYOD). To meet PCI and HIPAA requirements policies can be created where user roles and personal devices are granted or restricted from reaching workflows that have anything to do with credit card or ePHI resources. Additionally, restrictions can be implemented that deny personal devices from connecting to the guest network which will eliminate users from creating VPN connections back into enterprise network. The AirWave management suite can also help identify rogue APs and pinpoint where they are connected, for long and who has connected to these APs. There are specific reports within AirWave for PCI.
Does 11ac require RF planning?  Would you use directional antennas and sectorized cells?Yes, since it leverages the same 2.4GHz and 5GHz bands that were leveraged by 802.11n, you should do RF planning to properly design your AP placement and channel selections to deliver the best performance and coverage. Products like Aruba AirWave and Aruba VisualRF Plan are available to aid you in the planning process. Aruba customers can download the VisualRF Plan tool from our support website here. Most customers will be best served by leveraging the integrated omni-directional antennae that are built into the AP-225, however we do support external directional or sectional antennae with the AP-224.
How do you anticipate handling channel-planning techniques with the wider channel widths available in 802.11ac? Would this make it more complex and interfering in higher density deployments?You should perform RF planning to minimize the channel overlap in your deployment and maximize performance. With the wider 80MHz channels, there are still 5 non-overlapping channels that can be leveraged in your deployment. If your network has a mix of 802.11ac and 802.11n Access Points then you should also consider the 802.11n APs in your planning to minimize the occurrence of when APs need to fallback to narrower channels temporarily. Fortunately the standard was designed to allow for rapid negotiation of channel width so it can automatically drop down to 40MHz or 20MHz during interference times and return to 80MHz operation when possible.
When will the ArubaOS on the Controllers be able to run RF predictive coverage for 802.11ac?The current shipping version of the Aruba AirWave management suite already supports the ability to display predictive RF coverage maps for 802.11ac. More information on the AirWave product is available here.
When Multiple device connected will the speeds be down graded to the slowest connected like in N ?No, Aruba has capabilities like Airtime Fairness that keep the AP from throttling down if slower devices connect.
Is 802.11ac able to handle video streaming? (Netflix, Hulu plus)Yes with the higher throughput of the 802.11ac Access Points, video streaming can be supported with a large number of users. The growth of video streaming is one of the drivers why many organizations are rolling out 802.11ac today.
Did Yale run two GigE backhaul circuits to each access-point location?No. Yale University is currently leveraging one GigE link per AP.
Is David saying he has already rolled out 802.11ac across his whole campus?No, he rolled it out in a new building on campus and has validated 11ac before beginning a more significant rollout.
Are the 802.11 IEEE standards still a valid mechanism?  It is my belief that the wireless industry is moving ahead not waiting for any standard to be ratified.Yes. Wi-Fi Alliance is becoming the defacto for validating interoperability, both before and after ratification. But IEEE ratification is still a critical milestone for eliminating any doubt that things will change.
Is the Aruba 802.11ac AP-225 a dual-radio (A,B,G,N) product?Yes, the AP-220/IAP-220 Series of 802.11ac products are dual-radio with one radio in the 5GHz band for 802.11ac (and 11a/11n clients) and the second radio operates in the 2.4GHz band. This enables customers to support the newer 802.11ac devices while also supporting the legacy devices that can only operate in the 2.4GHz band.
Does Aruba have a webinar on the configuration of their Wi-Fi Access Points?We don't currently have any webinars that cover this topic. The best resource for learning out to configure and deploy an Aruba WLAN is our training portal, specifically the Mobility track, which is located here.