Shopping for Wave 2 Wi-Fi? Don't rush into it

The new world of Wi-Fi is a bit like the proverbial airplane being built in mid-air: Unless you really need to enter the new world of LANs right now, it might make sense to hold off. A case in point is the first 802.11ac Wave 2 access point from Cisco Systems, introduced on Tuesday in advance of the Cisco Live conference next week.

That Cisco Aironet 1850 Series Access Point, due to ship in July, can offer users a data rate of 1.7Gbps using both of the main Wi-Fi frequency bands. It can also transmit to three users at a time so they don’t have to share time on the network. That’s far short of what 11ac Wave 2 will ultimately deliver, with a theoretical speed of 6.8Gbps, but a big step up from Wave 1, which tops out at 1.3Gbps.

But the 1850 Series AP doesn’t come with the new multigigabit ethernet ports that are expected to help make Wave 2 Wi-Fi reach its potential. Instead of the new interfaces that can operate at 2.5Gbps or 5Gbps, the new Cisco APs come with two regular Gigabit ethernet ports.

The second wave of products built to the IEEE 802.11ac standard bring Wi-Fi throughput well above 1Gbps and can include other performance-boosting features. They’re just starting to go on sale now, and chips to power this new generation are in the spotlight this week at Computex in Taipei.

The souped-up Wi-Fi could mean a lot more packets flowing through each access point, ultimately too much to carry over the Gigabit ethernet interfaces that tie most APs back to wired LANs today. So there’s a new type of ethernet emerging to help IT departments take care of all that traffic without having to use 10-Gigabit ethernet, which requires newer cables that most users don’t have. A few products with a pre-standard form of this technology are starting to come out, too, and a standard is starting to come together.

Cisco is almost ready to ship such multigigabit ports for some of its wired switches, which are intended eventually to connect Wave 2 APs to the LAN. The eight-port Catalyst 3560-CX, and a 48-port module for the Catalyst 4500E chassis, both of which will have some multigigabit ports, are due to ship this month. A switch for the Catalyst 3850 line with multigigabit ports is set for July. Hewlett-Packard and other vendors also have switches with these ports in the pipeline.

Asked why the 1850 Series AP announced Tuesday won’t get the new ports, Cisco said they aren’t necessary on these products. The 1850 Series is designed for medium-size customers or the lower end of large enterprises. The size of their deployments and the density of use at their sites isn’t likely to generate more than 2Gbps of uplink traffic through the AP, Cisco said.

The APs will balance the traffic load between the two Gigabit ethernet ports to take advantage of their combined capacity, Cisco says. However, making that work would require two ethernet cables out to the AP.

Unless an enterprise already has twin wires to each AP, which is rare, pulling those cables would be an expensive step to take just to deploy this particular generation of product, Dell’Oro Group analyst Chris DePuy said.

“Hoisting the ladder is the most expensive part,” DePuy said. Avoiding cable installation is the main point of multigigabit ethernet, after all.

Cisco isn’t the only company coming out with a first-generation Wave 2 product with only Gigabit ethernet: The Ruckus Wireless ZoneFlex R710 likewise has two Gigabit ethernet wired interfaces. But he expects most Wave 2 products in the future to have multigigabit ethernet ports.

IT departments are likely to take a good, long look before committing to APs that don’t have the faster ports, because their needs could grow and change over time, DePuy said.

The market for such products may be fairly small, but it’s not nonexistent, DePuy said.

“It’s likely this is better than the Wave 1 products. So if you need to buy something now, this is the one you’re going to buy,” he said. “But if you can wait a little while, you might wait for the other ones.”

Meanwhile, there’s good news for IT shops that want to make sure they get multigigabit uplinks and can use them with different vendors’ products. The IEEE 802.3bz Task Force, formed earlier this year to set a standard for 2.5-Gigabit/5-Gigabit ethernet, adopted baseline proposals for all the main components of the specification at its first meeting in May. The group is now beginning to write the first preview draft of the standard and will next meet in July, said Dave Chalupsky, chairman of the task force.

“The process went as quickly as it possibly could,” Chalupsky said. The Task Force won’t have an official timeline for finishing the standard until after that meeting, but it’s possible the standard will be fully signed off by late 2016, he said. If that sounds like a long time, keep in mind that vendors often can safely develop interoperable products well before a standard is official.

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