802.11ac: Is Your Network Infrastructure Ready for Next-Gen Wi-Fi Traffic?

The next generation of Wi-Fi, 802.11ac couples the freedom of wireless with the speed of gigabit Ethernet. This also translates in additional load on the backbone of the network, which has to deliver at least 3 times the capacity of the current gold standard, the 802.11n based network.

Cisco launched the Unified Access architecture  to scale linearly with the increased load on the network with 60 Gbps Wi-Fi throughput on the Cisco 5760 Wireless LAN Controller and 40 Gbps Wi-Fi throughput on the Catalyst 3850 Series Switch with a built-in wireless controller.  Both these platforms are based on the Cisco Unified Access Data Plane (UADP) programmable ASIC, which provides high performance and scale, common open APIs, and enables consistent QoS policies for both wired and wireless networks.

Aruba recently launched the 7240 series controllers with a throughput of up to 40Gbps claimed, with the same goal of delivering 802.11ac capable performance across the network. This controller is based on a generic network processor and not a purpose built ASIC like the Cisco controller.

Miercom performed a third-party evaluation to benchmark these products  using  IMIX (Internet Mix) packet traffic and test QoS traffic for high priority application.  IMIX is traffic pattern consisting of a preset mixture of small, medium and large frame sizes used to emulate real-world traffic scenarios in a testing environment. We wanted to give you a sneak peek at some of the results.

Performance

Cisco 5760 is six times faster and Catalyst 3850 is 4 times faster as compared to Aruba 7240

The Cisco 5760, 3850 and the Aruba 7240 were tested for throughput using RFC 2544 and IMIX Traffic.  The Cisco 5760 and 3850 performed extremely well by achieving 50 Gbps and 37 Gbps, whereas Aruba 7240 fell short by just achieving 8 Gbps, which is 20% of its advertised throughput.

Cisco’s ability to handle more traffic throughput for small sized frames is based on the new custom built programmable ASIC called UADP ASIC. The Aruba 7200 series uses multiple network processors, but does not scale with the increase in the number of packets, leading to lower forwarding rate for smaller packets and hence a lower throughput.

Quality of Service (QOS)

802.11ac is about delivering an outstanding experience to each and every client served by an AP, even under demanding loads.  The Aruba 7240 and the Cisco 5760 controllers were tested for QoS for higher bandwidth application by transmitting video on the Aruba 7240 and Cisco 5760 and measuring image quality, in the presence of high volume background traffic.

Throughout QoS testing the video traffic was labeled to expedite forwarding. The Cisco 5760 showed reliable transmission of high priority traffic using strict priority queuing, which is implemented in hardware, while the Aruba 7240 controller lost a large amount of traffic because it was unable to honor an expedite forwarding label in software under simultaneously applied heavy data load tests.

Data Center Efficiency

Optimizing the overall power efficiency of the data center requires minimizing power level and consumption at every level within the infrastructure. To handle 50 Gbps of IMIX traffic on wireless network, you would need seven Aruba 7240 controllers versus just a single Cisco 5760 controller, resulting in up to seven times more Rack Unit (RU) space in the data center.  From the datasheet, each Aruba 7240 consumes about 165 watts of power, compared to 350 watts for a Cisco 5760. Drawing a power comparison graph (see below), Cisco is 330% more energy efficient for equivalent throughput performance and delivers more Gbps/watt.

The complete report is now available here: http://miercom.com/pdf/reports/20130508.pdf with the detailed testing methodology and statistics.

We would love to hear from you on your experiences with our controllers. Also, what do you think about our testing scenarios? Feel free to leave your comments below.

For more information on our 5760 Controller, check out the product page here.

For more information on the Catalyst 3850 Series Switch, join the Catalyst 3850 community, my3850.  http://cs.co/my3850

Other Resources

Product pages for datasheets: Cisco Catalyst 3850 and Cisco 5760 Controller

Webinars: Activate the IT Transformation with Cisco Unified Access: One Network parts 1 and 2 on the Community

NSA Show Podcasts on the Cisco Catalyst 3850, the Cisco 5760 Controller and Cisco 802.11ac