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WiFi

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Starbucks is shredding its deal in place since 2001, originally with MobileStar then T-Mobile, to switch to AT&T as their Wi-Fi provider. That moves 7,000 locations from T-Mobile’s ledgers of nearly 9,000 to AT&T’s. It turns AT&T from “McDonald’s plus,” with a relatively small footprint of other locations, to a 15,000-location giant. AT&T is also part of Boingo’s roaming network, which could mean (no news yet on this) that Boingo customers would suddenly add 7,000 highly desirable domestic roaming locations.

AT&T says in their press release that all Starbucks Card holders, which is simply their value-storing swipe card system, will get two hours of free Wi-Fi a day. This probably means you need to make a purchase with your card on that day to activate the two free hours. AT&T has also lowered the price for usage from T-Mobile’s somewhat egregious $6 per hour or $10 per day to $4 for a two-hour session. The monthly price, like the rest of AT&T’s network, is $20 per month for outsiders, and free to those with AT&T DSL.

And—yes, there’s an and—all Starbucks employees, 100,000 “partners” (read: wage slaves and management) get free access at all Starbucks locations. Which you have to admit is a nice perq.

Update: T-Mobile HotSpot subscribers will still be able to access Starbucks locations. Starbucks posted a separate press release stating that T-Mobile will be a roaming partner onto the AT&T network through a side deal; no additional cost is involved. There’s some leverage here, because T-Mobile does have about 2,000 other locations, including some premium airports like San Francisco. Existing roaming/aggregation deals among Boingo, AT&T, and T-Mobile were partly predicated on the airport market, where millions of subscribers to each network pass through each year.

source: http://wifinetnews.com/archives/008175.html

Wi Fi

Except for 802.11a, which operates at 5 GHz, Wi-Fi uses the spectrum near 2.4 GHz, which is standardized and unlicensed by international agreement

Wi-Fi is a brand originally licensed by the Wi-Fi Alliance to describe the underlying technology of wireless local area networks (WLAN) based on the IEEE 802.11 specifications. It was developed to be used for mobile computing devices, such as laptops, in LANs, but is now increasingly used for more services, including Internet and VoIP phone access, gaming, and basic connectivity of consumer electronics such as televisions and DVD players, or digital cameras. More standards are in development that will allow Wi-Fi to be used by cars in highways in support of an Intelligent Transportation System to increase safety, gather statistics, and enable mobile commerce (see IEEE 802.11p). Wi-Fi and the Wi-Fi CERTIFIED logo are registered trademarks of the Wi-Fi Alliance - the trade organization that tests and certifies equipment compliance with the 802.11x standards.

Wi Fi
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how it works

A typical Wi-Fi setup contains one or more Access Points (APs) and one or more clients. An AP broadcasts its SSID (Service Set Identifier, "Network name") via packets that are called beacons, which are usually broadcast every 100 ms. The beacons are transmitted at 1 Mbit/s, and are of relatively short duration and therefore do not have a significant effect on performance. Since 1 Mbit/s is the lowest rate of Wi-Fi it assures that the client who receives the beacon can communicate at at least 1 Mbit/s. Based on the settings (e.g. the SSID), the client may decide whether to connect to an AP. If two APs of the same SSID are in range of the client, the client firmware might use signal strength to decide which of the two APs to make a connection to. The Wi-Fi standard leaves connection criteria and roaming totally open to the client. This is a strength of Wi-Fi, but also means that one wireless adapter may perform substantially better than another. Since Wi-Fi transmits in the air, it has the same properties as a non-switched wired Ethernet network, and therefore collisions can occur. Unlike a wired Ethernet, and like most packet radios, Wi-Fi cannot do collision detection, and instead uses a packet exchange (RTS/CTS used for Collision Avoidance or CA) to try to avoid collisions.'

Advantages of Wi-Fi

• Allows LANs to be deployed without cabling, typically reducing the costs of network deployment and expansion. Spaces where cables cannot be run, such as outdoor areas and historical buildings, can host wireless LANs.

• Wi-Fi chipset pricing continues to come down, making Wi-Fi a very economical networking option and driving inclusion of Wi-Fi in an ever-widening array of devices.

• Wi-Fi products are widely available in the market. Different brands of access points and client network interfaces are interoperable at a basic level of service. Products designated as Wi-Fi CERTIFIED by the Wi-Fi Alliance are interoperable and include WPA2 security.

• Wi-Fi is a global set of standards. Unlike cellular carriers, the same Wi-Fi client works in different countries around the world.

• Widely available in more than 250,000 public hot spots and millions of homes and corporate and university campuses worldwide.

• As of 2006, WPA and WPA2 encryption are not easily crackable if strong passwords are used

• New protocols for Quality of Service (WMM) and power saving mechanisms (WMM Power Save) make Wi-Fi even more suitable for latency-sensitive applications (such as voice and video) and small form-factor devices

Disadvantages of Wi-Fi

• Spectrum assignments and operational limitations are not consistent worldwide; most of Europe allows for an additional 2 channels beyond those permitted in the US (1-13 vs 1-11); Japan has one more on top of that (1-14) - and some countries, like Spain, prohibit use of the lower-numbered channels. Furthermore some countries, such as Italy, used to require a 'general authorization' for any Wi-Fi used outside an operator's own premises, or require something akin to an operator registration.citation needed

• Equivalent isotropically radiated power (EIRP) in the EU is limited to 20dBm.

• Power consumption is fairly high compared to some other standards, making battery life and heat a concern.

• The most common wireless encryption standard, Wired Equivalent Privacy or WEP, has been shown to be breakable even when correctly configured. Wi-Fi Protected Access (WPA and WPA2) which began shipping in 2003 aims to solve this problem and is now generally available.

• Wi-Fi Access Points typically default to an open (encryption-free) mode. Novice users benefit from a zero configuration device that works out of the box but might not intend to provide open wireless access to their LAN.

• Many 2.4 GHz 802.11b and 802.11g Access points default to the same channel, contributing to congestion on certain channels.

• Wi-Fi networks have limited range. A typical Wi-Fi home router using 802.11b or 802.11g with a stock antenna might have a range of 45 m (150 ft) indoors and 90 m (300 ft) outdoors. Range also varies with frequency band, as Wi-Fi is no exception to the physics of radio wave propagation. Wi-Fi in the 2.4 GHz frequency block has better range than Wi-Fi in the 5 GHz frequency block, and less range than the oldest Wi-Fi (and pre-Wi-Fi) 900 MHz block. Outdoor range with improved antennas can be several kilometres or more with line-of-sight.

• Wi-Fi pollution, meaning interference of a closed or encrypted access point with other open access points in the area, especially on the same or neighboring channel, can prevent access and interfere with the use of other open access points by others caused by overlapping channels in the 802.11g/b spectrum as well as with decreased signal-to-noise ratio (SNR) between access points. This can be a problem in high-density areas such as large apartment complexes or office buildings with many Wi-Fi access points.

• It is also an issue when municipalities or other large entities such as universities seek to provide large area coverage. Everyone is considered equal when they use the band (except for amateur radio operators who are the primary licensee). This openness is also important to the success and widespread use of Wi-Fi, but makes it unsuitable for "must have" public service functions.

• Interoperability issues between brands or deviations from the standard can disrupt connections or lower throughput speeds on other user's devices within range. Wi-Fi Alliance programs test devices for interoperability and designate devices which pass testing as Wi-Fi CERTIFIED.

• Wi-Fi networks can be monitored and used to read and copy data (including personal information) transmitted over the network unless encryption such as WPA or VPN is used.

Standard Devices

Wireless Access Point (AP)

A wireless access point connects a group of wireless devices to an adjacent wired LAN. An access point is similar to an ethernet hub, relaying data between connected wireless devices in addition to a (usually) single connected wired device, most often an ethernet hub or switch, allowing wireless devices to communicate with other wired devices.

Wireless Adapter

A wireless adapter allows a device to connect to a wireless network. These adapters connect to devices using various interconnects such as PCI, USB, and PCMCIA.

Wireless Router

A wireless router integrates a WAP, ethernet switch, and internal Router firmware application that provides IP Routing, NAT, and DNS forwarding through an integrated WAN interface. A wireless router allows wired and wireless ethernet LAN devices to connect to a (usually) single WAN device such as cable modem or DSL modem. A wireless router allows all three devices (mainly the access point and router) to be configured through one central utility. This utility is most usually an integrated web server which servers web pages to wired and wireless LAN clients and often optionally to WAN clients. This utility may also be an application that is run on a desktop computer such as Apple's AirPort.

Wireless Ethernet Bridge

A wireless Ethernet bridge connects a wired network to a wireless network. This is different from an access point in the sense that an access point connects wireless devices to a wired network at the data-link layer. Two wireless bridges may be used to connect two wired networks over a wireless link, useful in situations where a wired connection may be unavailable, such as between two separate homes.

Range Extender

A wireless range extender or wireless repeater can extend the range of an existing wireless network. Range extenders can be strategically placed to elongate a signal area or allow for the signal area to reach around barriers such as those created in L-shaped corridors. Wireless devices connected through repeaters will suffer from an increased latency for each hop. Additionally, a wireless device at the end of chain of wireless repeaters will have a throughput that is limited by the weakest link within the repeater chain.

Non-Standard Devices

DIY Range Optimizations

USB-Wi-Fi adapters, food container "Cantennas", parabolic reflectors, and many other types of self-built antennae are increasingly made by do-it-yourselvers.citation needed For minimal budgets, as low as a few dollars, signal strength and range can be improved dramatically. There is also a type of optimization by polarizing the signal to achieve a planar coverage like a plate.

Long Range Wi-Fi

Recently, long range Wi-Fi kits have begun to enter the market. Companies like RadioLabs and BroadbandXpressoffer long range, inexpensive kits that can be setup with limited knowledge. These kits utilize specialized antennas which increase the range of Wi-Fi dramatically, in the case of the world record 137.2 miles 3. These kits are commonly used to get Broadband internet to a place that cannot access the service itself. For more information see Long Range Wi-Fi.

What are "GloboTrends?"

“GloboTrends” are fundamental underlying trends, which means that they are important, but might not be obvious. Many trends are interconnected, and have global implications. Not paying attention to the development of global trends in can come back to haunt any business person, and so… we have dedicated ourselves to summarizing these events in simple language, and we are trying to show how these events might be important to different regions, and to different industries.