But my n Is Only 2 Years Old. Matt Williams IT Manager, Wireless Kent State University

Transcription

1 But my n Is Only 2 Years Old Matt Williams IT Manager, Wireless Kent State University

2 Disclaimer All observations, opinions, and suggestions herein are my own based on my environments and experiences. All environments are different. There are no cookie cutter design solutions. I m not a spokesperson for any particular vendor, though some names will inevitably come up.

3 Introduction About me US Army Vet 4 years in South Korea Air Defense Artillery 2+ years with DISA Information Security Been with Kent State University for 8 months Spend my free time with my children

4 Kent State University

5 At a glance Ohio s second largest state university Main campus and 8 regional campuses 46,000 students enrolled this semester Approx. 4,050 employees About 20,000 concurrent wireless devices at peak 2,900+ APs spread across all campuses

6 Sample Design 2010 Began 3 yr n project Phase 1 1:1 replacement of a/b/g APs Located in academic spaces and res hall lounges Approximately 300 APs High Density APs weren t available (not that it would have mattered)

7 Sample Design 2011 Phase 2 Residence hall room coverage Added about 300 additional APs Started seeing two wireless devices per user

8 Sample Design 2012 Phase 3 Fill any coverage gaps Ended up adding another 250 APs Up to three wireless devices per user

9 Sample Design

10 Intent Hallway deployment Easy physical access Designed for max coverage Specifically 2.4GHz coverage Specifically for laptops Minimize capital costs

11 Consequences Aggressive roaming from clients Specifically Macs

12 Consequences AP line of sight Constant Tx power changes Can t support high number of clients AP saturation New coverage gaps Massive frustration

13 802.11n Project Summary No good deed goes unpunished A lot of capital expense And constant gap filling A ton of operation expense ac to the rescue?

14 How do we fix this? Option 1: Utilize controller features Band steering Data rate limit enforcement Option 2: Replace existing APs with high density APs Option 3: Select a different vendor or product Option 4: Complete redesign

15 Redesign Considerations Do you have an accurate view of the RF environment? Do you have different requirements for different spaces? Academic vs. residential Faculty/Staff vs. student requirements Sales floor vs. shipping/receiving Dining area vs. register area Outdoor coverage?

16 Balancing Requirements How do you support a reasonable quality of life for your customers? Video streaming, gaming, presence apps, access to campus resources, etc. How do you support faculty research and staff requirements? Access to ERP and CRM, wireless IoT research/sensor networks, AirPrint and AirPlay, etc. How do you do that while supporting the explosion of wireless devices?

17 How does ac fit in? Is it worth adopting Wave 1? Should we limp along until Wave 2 is released? Should we just redesign with n and redesign again when the next evolution of comes out? How will ac affect my wired environment? Do I have any regulatory requirements?

18 802.11ac Considerations Wave 1 Negligible cost difference between n and Wave 1 products Better chipsets, support more clients, and performance than N products 5GHz attenuation and cell size Wired infrastructure implications Do we really need two uplinks to each AP? Do I need new switches with PoE+ and 10GbE uplinks? What does that do to my core and distribution layers?

19 802.11ac Considerations Wave MHz channels deplete the number of channels available Wired infrastructure implications How many wires will be needed? 10 Gbps to the AP? Nbase-T? What about switch uplinks? When will we see client devices that use 4 SS?

20 Redesign Decisions Design decisions Benchmark -65 dbm on smartphone or other handheld device Move APs out of the hallway and into rooms Adopt ac Better chipsets Supports more clients per AP Reuse n where possible Smaller cells reduce associations per AP Saves money

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23 Redesign Decisions Infrastructure decisions Add new wiring as buildings receive other renovations Reuse existing wiring where possible Install 2 Cat 6a station wires in all new locations All new switches are PoE+ (802.3at) 24-port switches Currently using 1GbE uplinks until 10GbE is needed

24 Redesign Decisions Installation decisions Res Halls Wiremold Mount to wall plate Academic Spaces Above ceilings where required Investigating benefits of dropping them below deck Repurpose as much technology as possible

25 My Observations Design for what you want out of your network Design for 5GHz at no more than -65 on a lower end consumer handheld device Install infrastructure to aid expansion Pull two wires the first time in hard to reach locations Try to reuse wiring wherever possible Deploy switches that make sense for your environment

26 Lessons Learned Stop deploying in hallways Controller software can t mitigate physical construction Work with facilities/architects and be prepared for questions More and more concern about long term affects of Wi-Fi Have a plan in place if there are complaints I don t know what the future holds, but WLAN spectrum use has been cyclical Ignore the marketing hype You probably don t won t need 2 Cat6a cables anytime soon. You likely won t need 10GbE switch uplinks anytime soon All environments are different

27 Questions