Recently in WiMAX Category

There is a portion of the American Recovery And Reinvestment Act that will fund programs to accelerate the deployment and use of broadband in the United States. In particular, the NTIA's Broadband Technology Opportunities Program (BTOP) and the Department of Agriculture's Rural Utility Services (RUS) grants and loans will go to fund programs "in unserved, underserved, and rural areas and to strategic institutions that are likely to create jobs or provide significant public benefit". These programs are handing out billions of dollars in the next 18 months and will likely have thousands of applicants for the much needed stimulus money. How will these agencies do it? It is a daunting task and efforts are already underway. The first open public meeting was held earlier this week and two more will be held in the coming weeks. At this point there are more questions than answers. How are these agencies going to work together? Who is eligible to receive a grant? How will the success of the program be measured overall? What does "underserved" mean? For that matter - what does "broadband" mean? In the new era of transparency and accountability, grant applicants will have to explain how they are going to execute their program, deliver the claimed benefits, and measure the results. For the wireless broadband piece, this brings us right back to the basics. What are the technical requirements to support a given application - coverage, throughput, latency and overall system capacity? In order to support multiple different applications, what are the system level requirements? What performance is required to deliver an acceptable user experience? Perhaps it is time to dust off our Novarum lessons from the first round of Municipal Wireless. We can not afford to repeat those mistakes again.

Two of the important issues in large scale wireless have been:

1. Can a given technology provide a usable data communications service and
2. How much does it cost to deploy such a service.

A useful network service provided at an affordable price are necessary preconditions for a successful network offering. Many of the early muni WiFi networks were hampered by the double whammy of both a poor service AND the higher cost to deploy than expected. In seeking to answer this, Novarum structured its’ Wireless Broadband Review to provide some of this information. During 2007 and early 2008, we tested cellular, WiFi and pre-WiMax networks in these cities: Anaheim CA (2x), Brookline MA, Chico CA, Cupertino CA, Daytona FL, Eugene OR, Galt CA, Longmont CO, Madison WI, Minneapolis MN, Mountain View CA (2x), Palo Alto CA, Philadelphia PA (2x), Portland OR (2x), Raleigh NC, Rochelle IL, St. Cloud FL (2x), Santa Clara CA, Sunnyvale CA, and Tempe AZ (2x). In several cities we tested twice to detect changes in traffic and improvements in network service over time and experience. We discovered that, on average, all of these networks have similar performance and coverage, but that the best of the WiFi networks substantially outperformed the best of either the cellular AND pre-WiMax networks. Our test was an apples to apples comparison of performance (delay, uplink throughput, downlink throughput) and availability (percentage of tested locations with service within the advertised service area) for all of the major network technologies:

1. ATT (Cingular), Sprint and Verizon cellular data networks
2. A number of metro WiFi networks using equipment by BelAir, SkyPilot, Strix, Tropos, and
3. Four of ClearWire’s pre-WiMax networks.

We tested outdoor coverage in an average of 20 locations per city - testing all networks with the same traffic load and in the same location and time. One of the important determinants of good performance is a good client modem - and we tested with a variety of client modems. For today’s thoughts, we’ll look at standard USB external modems for each of the cellular data networks, a higher power WiFi modem (noting that current 802.11n modems appear to perform on par with these higher power clients), and a desktop directional CPE for the pre-WiMax ClearWire networks (no portable device was available) at the time. We would expect the WiMax modem (AC powered, directional antenna) to have the advantage in performance. To our surprise, with similar client modems, averaged over good and bad networks, WiFi networks delivered almost 3x better performance than cellular networks and materially better performance than pre-WiMax networks - with similar levels of availability of service over the promised coverage area for all three network technologies.

Network	Delay (msec)	Uplink (kbps)	Downlink (kbps)	Availability
Average Cellular	340	195	507	89%
Average pre-WiMax	174	169	1124	83%
Average WiFi	113	767	1286	85%

If we look at the best, and most recently deployed WiFi network, we see performance and availability superior to the best the cellular data networks (by a factor of 3!) AND the best of pre-WiMax networks we measured - by at least a factor of 2.

Network	Delay (msec)	Uplink (kbps)	Downlink (kbps)	Availability
Best Cellular	192	612	980	100%
Best pre-WiMax	190	164	1129	100%
Best WiFi	63	2062	2949	100%

The measured performance demonstrate that WiFi networks materially outperform cellular data networks AND pre-WiMax networks - and do it with similar service area coverage. And likely lower deployment costs.

One of the smaller towns we tested in the NWBR was Rochelle, IL - a farming town of 10,000 people about 75 miles West of Chicago. In this case the ISP providing wireless internet service was the city itself through the Rochelle Municipal Utilities organization - along with power and water. It was an interesting experience going to the small office, right next store to the window where a citizen would pay their electric bill, to shop and sign up for Internet service ... with a variety of recommended CPE devices displayed on the wall. One the key items we argue about in building municipal networks is ownership - who should own and operate the network? And here in Rochelle was a rather good wireless network that was built by the town. And clearly where other options for broadband access offer poor performance or do not exist (The city started by offering dial-up Internet access and the wireless cellular carriers offer spectacularly poor wireless data products - the city’s networks offers roughly 20x the performance of the sadly 2G wireless cellular networks in the town.) This reminded me of the Rural Electrification Project (that had originally sponsored bringing electricity to Rochelle after WWII) - (from Wikipedia): In 1936 the Rural Electrification Act was enacted. Also, the Tennessee Valley Authority is an agency involved in rural electrification. The Rural Electrification Administration (REA), a former agency of the U.S. Department of Agriculture, was charged with administering loan programs for electrification and telephone service in rural areas. The REA was created in 1935 by executive order as an independent federal bureau, authorized by the United States Congress in 1936, and later in 1939, reorganized as a division of the U.S. Dept. of Agriculture. The REA undertook to provide farms with inexpensive electric lighting and power. To implement those goals the administration made long-term, self-liquidating loans to state and local governments, to farmers' cooperatives, and to nonprofit organizations; no loans were made directly to consumers. In 1949 the REA was authorized to make loans for telephone improvements; in 1988, REA was permitted to give interest-free loans for job creation and rural electric systems. By the early 1970s about 98% of all farms in the United States had electric service, a demonstration of REA's success. The administration was abolished in 1994 and its functions assumed by the Rural Utilities Service. The Rural Electrification Administration (REA) was an agency of the United States federal government created on May 11, 1935 through efforts of the administration of President Franklin D. Roosevelt. The REA's task was to promote electrification in rural areas, which in the 1930s rarely were provided with electricity due to the unwillingness of power companies to serve farmsteads. America lagged significantly behind European countries in rural electrification. Private electric utilities argued that the government had no right to compete with or regulate private enterprise, despite many of these utilities having refused to extend their lines to rural areas, claiming lack of profitability. Since private power companies set rural rates four times as high as city rates, this was a self-fulfilling prophecy.[1] Under the REA program there was no direct government competition to private enterprise. Instead, REA made loans available to local electrification cooperatives, which operated lines and distributed electricity. By 1939 the REA served 288,000 households, prompting private business to extend service into the countryside and to lower rates. By the end of the decade, forty percent of rural homes had power, up from around 10% in 1930. From 1949, the REA could also provide assistance to co-operative telephone companies. In ten years, rural electrification increased from 10% of rural homes to 40% by 1940. So why can’t we use this already successful model of the Rural Electrification Project as the basis for government deploying broadband, particularly in less developed areas? While some of the early attempts at municipal wireless were not considered successful (Philadelphia, for example) they had the clear effect of dropping the local cost of wired broadband access. Competition beyond the entrenched monopolies of DSL and cable is a good thing.

We have been curious about how real wireless networks perform - both in the enterprise and in metropolitan areas. We have also been impressed by how few third party measurements at scale have been performaned for both applications of wireless networks. Most of our knowledge about how these networks really deliver service is either based on anecdotal reports or the marketing information from the service providers and equipment vendors. So we decided to test and obtain some real, non-partial information. We went out and tested over 136 wireless networks in 22 North American cities from July 2006 through early 2008. We devised an network independent testing regime that mimics the behaviour that ordinary users of these services would observe - testing packet delay, upload and download throughput (using industry standard tools) and percentage of the claimed service area in which we could actually get service. We tested in the following cities (some twice to reflect major changes in the networks between tests): Anaheim CA (2x), Brookline MA, Chico CA, Cuperino CA, Daytona FL, Eugene OR, Foster City CA, Galt CA, Longmont CO, Madison WI, Minneapolis MN, Mountain View CA (2x), Palo Alto CA, Philadelphia PA (2x), Portland OR (2x), Raleigh NC, Rochelle IL, St. Cloud FL, Santa Clara CA, Sunnyvale CA, Tempe AZ, and Toronto ON (2x). Where we could find them, we tested cellular data networks from ATT (nee’ Cingular), Sprint and Verizon; pre-WiMax networks from ClearWire and WiFi networks from a variety of ISPs. The data clearly shows that all these technologies can deliver similar levels of service when properly built out. Subsequent blogs will address individual lessons learned for each of these network technologies.

This blog is the combined thoughts of Ken Biba and Phil Belanger ... two pioneers of wireless networking and arguably two of the co-inventors of the networking systems we think of as WiFi:

1. Minimal licensing.
2. Sharing of scarce radio spectrum.
3. Robust technologies that survive (and often prosper) in a severe radio environment.
4. Dirt cheap.
5. Ubiquitous.
6. High performance.

Look for us to be posting product critiques, technology thoughts and the results from our ongoing measurements of both enterprise and municipal networks. Over the last 18 months, we have done extensive studies of many of the foundation myths of deploying large scale wireless networks in both large enterprise and metropolitan environments. We will be reporting on those studies here and many of the implications of those studies on future use of unlicensed technology for providing mission critical network services. The Novarum Wireless Broadband Review surveyed and measured over 100 deployed municipal WiFi, cellular and pre-standard WiMax networks and comprises the largest available database of experience about these networks. We will be using this large experience base to inform our comments ... rather than mere opinion. We look forward to your comments.