Wireless Andrew 2.0. February 13, Dan McCarriar Director, NICS

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Wireless Andrew 2.0 February 13, 2012 Dan McCarriar Director, NICS dlm@cmu.

1 Wireless Andrew 2.0 February 13, 2012 Dan McCarriar Director, NICS Agenda The history of Wireless Andrew Wireless standards n at Carnegie Mellon Planning the upgrade Deploying the network Deployment and policy issues Wireless stats and adoption Futures Q&A 2 1

2 History of Wireless Andrew 1994: Began as an NSF-funded research project 1997: Phase I network deployed, covering about 50% of academic spaces 1997: IEEE publishes new standard for wireless LANs 1998: Partner with Lucent Technologies, replace everything with newly standardized products, 100% coverage in academic spaces by : Network extended to residence halls, now 100% coverage across campus 2008: Network upgraded to n 2014:? 3 All-Wireless Campus? Not likely to happen at Carnegie Mellon Though we are seeing demand for wired ports decrease Recently removed more than 300 switch ports from residence halls Currently working on right-sizing the academic/administrative wired network The first wireless-only residence hall went online in Fall 2010 Keep in mind that all of this wireless stuff has a wired network behind it All that said, wireless is probably viable as the primary network for 90% of applications 4 2

3 Wireless Standards Wireless standards are established by the Institute of Electrical and Electronics Engineers (IEEE) Standard Ratification Date Frequency Max Speed Real Speed GHz 2 Mbps 1 Mbps b GHz 11 Mbps 4-5 Mbps a GHz 54 Mbps 23 Mbps g GHz 54 Mbps 19 Mbps n or 5 GHz Mbps Varies ac GHz ~ 1Gbps Varies ad /5/60 GHz ~ 7Gbps Varies n Technology MIMO Multiple input, multiple output Uses multiple spatial streams to transmit more information over the same frequency using multiple antennae. AxB:C notation. We currently use 3x3:2 radios. Channel Bonding Combines two 20 MHz channels (as used in older b/g/a standards) into one 40 MHz channel 6 3

4 Planning the Upgrade Why n? Last upgrade of Wireless Andrew in 2001 One-time funding available for replacement of entire network, had to be spent by September 08 No funding commitment (yet) for regular equipment refresh Final n standard was not ratified, but Wi-Fi Alliance was certifying n draft 2.0 products 7 Planning the Upgrade - Requirements Full coverage in every campus building, both academic/administrative and residences Capacity for advanced applications IP multicast video, VoIP, etc n draft 2.0 compliant Also must have a reasonable (i.e. free) upgrade path to the final standard Speed and capacity for wired network replacement 8 4

5 Planning the Upgrade - Vendor Selection RFP issued April responses On-site vendor conferences with each 3 finalists On-site equipment testing in real-world scenarios Nobody had real n equipment yet Vendors selected September 2007 Aruba Networks Xirrus 9 Deploying the Network Site Surveys Using AirMagnet Survey product Passive surveys Target -70 RSSI in all spaces Audit with active surveys after product is installed Many tools didn t understand n yet. We surveyed for an a deployment. Today, we survey for n coverage in 5 GHz. 10 5

Deploying the Network Site Surveys Deploying the Network (cont.) Physical Plant Using midspan PoE devices (most 802.

6 Deploying the Network Site Surveys Deploying the Network (cont.) Physical Plant Using midspan PoE devices (most n access points struggle with standard 15.4W 802.3af PoE) Two Cat 5e wires to each access point location Power upgrades in some IDFs Aesthetics of n access points 12 6

7 The Aesthetics of 11n 13 The Aesthetics of 11n (cont.) 14 7

8 The Aesthetics of 11n (cont.) 15 Deploying the Network (cont.) Network Design Location and capacity of controllers (we use a central controller design) We originally thought the central controller design would be an issue. It hasn t been. GigE ports for access points n in 2.4 GHz vs. 5 GHz vs. both Channel planning 16 8

9 Deployment Issues DFS2 Support FCC ruling (effective July 2007) governing WLAN systems operating in certain 5 GHz frequencies Need to coexist with military and weather radar 3 rd party lab testing vs. FCC testing 17 Deployment Issues (cont.) 2.4 GHz Ch# Full DFS2 Support 5 GHz Ch#

10 Deployment Issues (cont.) 2.4 GHz Ch# Full DFS2 Support Bonded Channels 5 GHz Ch# Deployment Issues (cont.) 2.4 GHz Ch# No DFS2 Support Bonded Channels 5 GHz Ch#

11 Policy Issues Guest access to wireless network wide open or controlled? Obvious security issues Possible CALEA implications CMU airspace policy Current policy covers 2.4 GHz Recently updated to cover 5 GHz FCC support for university-owned residences 21 Wireless Stats Two vendors: Aruba Networks and Xirrus Approximately 4.1M sq. ft. of in-building space to cover with wireless 11,000+ unique devices on the wireless network in any given 24-hour period 1717 Aruba AP-125 access points, 8 M3 controllers 348 Xirrus XN8 arrays 22 11

12 What We re Seeing Clients (2008) b: 1% g: 58% a: 5% n: 36% 23 What We re Seeing Clients (2012) b: 0% g: 12% a: 1% n: 87% 24 12

13 What We re Seeing Speeds (2009) 25 What We re Seeing Speeds (2012) 26 13

14 Top Issues Client driver updates Enhancements are released regularly, people don t update their software Coverage 100% coverage of indoor areas, but not perfect in some challenging buildings (Wean, etc.) Capacity Number of devices on the network has exploded over the past 4 years This has been more of an issue with IP address pools, large broadcast domains, etc. Occasional issues in large classrooms, events 27 What s Next Enhanced n outdoor coverage (stadium, Flagstaff, UC courtyard, cut, etc.) WPA2-enabled network ( CMU-SECURE ) 3-stream n radios, upping max throughput (theoretical) to 450 Mbps ac/ad Gig wireless Will 4G carrier networks make this all a moot point? 28 14

15 What s Next (cont.) r fast handoff between APs via techniques like OKC. Reduces roam time from ms to 20-25ms k radio resource management. APs get info on and advertise their near neighbors (SSIDs, encryption capabilities, load, channels used) v kitchen sink of client configuration options 29 Q&A Questions? 30 15

16 Thanks! Dan McCarriar 16

Wireless Andrew 2.0. March 2, Dan McCarriar Director, Network and Production Services

Wireless Andrew 2.0. March 2, Dan McCarriar Director, Network and Production Services Wireless Andrew 2.0 March 2, 2009 Dan McCarriar Director, Network and Production Services dlm@cmu.edu Agenda The history of Wireless Andrew The all-wireless campus? Quick wireless overview 802.11n at Carnegie