Archive for December, 2005

Inmarsat’s global broadband network takes to the skies

UK-based satellite operator Inmarsat this week switched on the first of two satellites offering mobile voice and high speed IP data services in the latest stage of a six-year project costing Eur1.3 billion.

The project, dubbed Broadband Global Area Network (BGAN), is designed to provide both mobile voice and broadband data simultaneously, with guaranteed IP data rates on demand. The latest move follows on from the launch of two of the world’s largest commercial satellites in March and November of this year.

Initially, BGAN will provide services across Europe, Africa, the Middle East and Asia, but following the activation of the operator’s second satellite, services will be extended to North and South America in the second quarter of 2006.

Ultimately, the two I-4 satellites will deliver broadband coverage across 85 per cent of the world’s landmass and 98 per cent of the world’s population, delivering IP data speeds of up to 492kbps, with guaranteed data rates up to 256kbps, potentially making it faster than 3G UMTS services.

Users would be able to browse the web, use email and stream video, audio and voice calls, all over a secure IP VPN connection, while the service launch is supported by a range of lightweight satellite terminals, similar in size to a standard laptop.

Source: vnunet.com

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QUALCOMM Reinforces Commitment to WLAN Market, Joins Wi-Fi Alliance

QUALCOMM Incorporated, a leading developer and innovator of Code Division Multiple Access (CDMA) and other advanced wireless technologies, today announced that the Company has joined the Wi-Fi Alliance. The Wi-Fi Alliance is a global, non-profit industry trade association with more than 200 member companies devoted to promoting the growth of wireless local area networks (WLAN). By joining the Wi-Fi Alliance, QUALCOMM will be directly involved with ensuring the compatibility of Wi-Fi technology with the Company’s Mobile Station Modem(TM) (MSM(TM)) chipsets.

“QUALCOMM is pleased to take the important step of joining the Wi-Fi Alliance to help ensure the interoperability of WLAN technologies with CDMA2000, WCDMA, and other wireless standards supported by our solutions,” said Ed Tiedemann, senior vice president of engineering for QUALCOMM. “We look forward to working closely together on the interoperability of 802.11 a, b, and g standards — as well as the expected 802.11n standard — with cellular networks, helping ensure seamless compatibility across our product portfolio and driving the convergence of mobile capabilities.”

“In becoming a member of the Wi-Fi Alliance, QUALCOMM joins more than 200 companies from around the globe who are committed to delivering interoperable Wi-Fi solutions and ensuring a positive user experience through our Wi-Fi CERTIFIED programs,” said Frank Hanzlik, Wi-Fi Alliance managing director. “We are pleased to have them become a part of the organization.”

QUALCOMM recently announced that select MSM chipsets will be integrated with WLAN modules to offer connectivity to IP networks, and will feature compatibility with 802.11b and 802.11g protocols on CDMA2000® and WCDMA (UMTS®) networks. QUALCOMM’s contributions to 802.11n technology include MIMO and Transmit Beamforming techniques that will help accelerate convergence between the computing, consumer electronics and mobile phone segments.

With the aim of enhancing the user experience for mobile wireless devices, the Wi-Fi Alliance’s testing and certification programs ensure the interoperability of WLAN products based on the IEEE 802.11 specification. Since the introduction of the Wi-Fi Alliance’s certification program in March 2000, more than 2,000 products have been designated as Wi-Fi CERTIFIED(TM), encouraging the expanded use of Wi-Fi products and services across the consumer and enterprise markets.

From Qualcomm’s press release.

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Universal Mobile Telecommunications System - UMTS

Universal Mobile Telecommunications System (UMTS) is one of the third-generation (3G) mobile phone technologies. It uses W-CDMA as the underlying standard, is standardized by the 3GPP, and represents the European/Japanese answer to the ITU IMT-2000 requirements for 3G Cellular radio systems.

To differentiate UMTS from competing network technologies, UMTS is sometimes marketed as 3GSM, emphasizing the combination of the 3G nature of the technology and the GSM standard which it was designed to succeed.

Features
UMTS supports up to 1920 kbit/s data transfer rates (and not 2 Mbit/s as frequently seen), although at the moment users in the real networks can expect performance up to 384 kbit/s - in Japan upgrades to 3 Mbit/s are in preparation. However, this is still much greater than the 14.4 kbit/s of a single GSM error-corrected circuit switched data channel or multiple 14.4 kbit/s channels in HSCSD, and - in competition to other network technologies such as CDMA-2000, PHS or wLAN - offers access to the World Wide Web and other data services on mobile devices.

Precursors to 3G are 2G mobile telephony systems, such as GSM, CDMA, PDC, PHS and other 2G technologies deployed in different countries. In the case of GSM, there is an evolution path from 2G, called GPRS, also known as 2.5G. GPRS supports a much better data rate (up to a theoretical maximum of 140.8kbit/s, though typical rates are closer to 56kbit/s) and is packet switched rather than connection oriented (circuit switched). It is deployed in many places where GSM is used. E-GPRS, or EDGE, is a further evolution of GPRS and is based on new “coding schemes”. With EDGE the actual packet data rates can reach around 180 kbit/s (effective). EDGE systems are often referred as “2.75G Systems”.

In 2006, UMTS networks in Japan will be upgraded with High Speed Downlink Packet Access (HSDPA), sometimes known as 3.5G. This will make a downlink transfer speed of up to 14.4 Mbit/s possible. Work is also progressing on improving the uplink transfer speed with the High-Speed Uplink Packet Access (HSUPA)

Marketing material for UMTS has emphasised the possibility of mobile videoconferencing, although experience in Japan and elsewhere has shown that user demand for Video calls is not very high.

Other possible uses for UMTS include the downloading of music and video content.

Simply put, UMTS is the combination of the W-CDMA air interface (the protocol that defines over-the-air transmissions between UMTS mobile phones and towers), GSM’s Mobile Application Part (MAP) core (the protocol that provides mobile functionality like to route calls to and from mobile subscriber), and the GSM family of speech codecs like AMR and EFR (the protocols which define how audio is digitized, compressed and encoded). Technically speaking, W-CDMA (as per the definition of IMT2000) is merely the air interface, while UMTS is the complete stack of communication protocols designated for 3G global mobile telecommunications and as a direct successor to GSM. However, W-CDMA is frequently used as a general, umbrella term to collectively refer to the family of 3G standards that uses W-CDMA as its air interface, that includes UMTS, FOMA and J-Phone.

Like other real-world W-CDMA implementations, UMTS uses a pair of 5 MHz channels, one in the 1900 MHz range for uplink and one in the 2100 MHz range for downlink. In contrast, CDMA2000 uses one or more arbitrary 1.25 MHz channels of each direction of transmissions. UMTS is frequently criticized for its heavy bandwidth requirements.

The specific frequency bands originally defined by the UMTS standard are 1885-2025 MHz for uplink and 2110-2200 MHz for downlink. See #External links at the bottom of this page for a map of UMTS frequency allocation.

For existing GSM operators, it is a simple but costly migration path to UMTS: most of the rest of their infrastructures may remain the same, but the cost of obtaining new spectrum licenses and overlaying UMTS at existing towers can be prohibitively expensive.

A major difference of UMTS compared to GSM is the air interface forming Generic Radio Access Network (GRAN). It can be connected to various backbone networks like the Internet, ISDN, GSM or to a UMTS network. GRAN includes the three lowest layers of OSI model. The network layer (OSI 3) protocols form the Radio Resource Management protocol (RRM). They manage the bearer channels between the mobile terminals and the fixed network including the handovers.

Other competing standards
There are other competing 3G standards, such as CDMA2000 and systems including iBurst from Arraycom, Flarion and wCDMA-TDD (IPWireless).

Both CDMA2000 and W-CDMA are accepted by ITU as part of the IMT-2000 family of 3G standards, in addition to Enhanced Data Rates for Global Evolution (EDGE) and China’s own 3G standard, TD-SCDMA.

CDMA2000, being an evolutionary upgrade to cdmaOne, does not require new spectrum allocation and will operate comfortably in existing PCS spectrums.

Most existing GSM operators take a wait-and-see approach to UMTS, due to the high cost of obtaining new frequency spectrums and equipment.

Most GSM operators in North America have accepted EDGE as a temporary 3G solution. AT&T Wireless launched EDGE nationwide in 2003, Cingular launched EDGE in most markets and T-Mobile USA has launched EDGE nationwide as of October 2005. Rogers Wireless launched nation-wide EDGE service in late 2003 for the Canadian market. TIM (Italy) launched EDGE in 2004. The benefit of EDGE is that it leverages existing GSM spectrums and is compatible with existing GSM handsets. EDGE provides a short-term upgrade path for GSM operators and directly competes with CDMA2000.

From the Wikipedia article on Universal Mobile Telecommunications System

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Internet Explorer flaw may expose personal information via Google Desktop

A security researcher in Israel has found a way to steal information from unwitting users of Google’s desktop search tool by exploiting an unpatched flaw in Microsoft’s ubiquitous Internet Explorer.

There is a bug in the way the Web browser processes CSS rules, Matan Gillon wrote in a description of his hack posted on Wednesday. CSS, or Cascading Style Sheets, is a method for setting common styles across multiple Web pages. The Web design technique is widely used on many sites across the Internet.

The proof-of-concept method is an example of how security flaws in software can offer all kinds of access to programs on vulnerable PCs, including to Google Desktop.

This design flaw in IE allows an attacker to retrieve private user data or execute operations on the user’s behalf on remote domains” Gillon wrote in his description of the attack method. He crafted a Web page that–when viewed in IE on a computer with Google Desktop installed–uses the search tool and returns results for the query “password.

To exploit the flaw, an attacker has to lure a victim to a malicious Web page. “Thousands of Web sites can be exploited, and there isn’t a simple solution against this attack, at least until IE is fixed” Gillon wrote.

Microsoft is investigating the issue, which it described in a statement as a problem affecting the cross-domain protections in Internet Explorer. “This issue could potentially allow an attacker to access content in a separate Web site, if that Web site is in a specific configuration” Microsoft said in the statement.

Microsoft is not currently aware of malicious code that takes advantage of the flaw, but is monitoring the situation, the company said. A security update or an advisory on the problem may be coming, it said.

Google is also investigating Gillon’s findings. “We just learned of this issue and are looking into it” Sonya Boralv, a spokeswoman for the search giant, wrote in an e-mailed statement.

While Gillon in his example uses the IE flaw as a means to get to Google Desktop, this flaw and other software bugs could be used to covertly access virtually any application on a compromised computer.

It is like any other flaw within IE, but he got creative and used it to launch Google Desktop to retrieve data” security researcher Tom Ferris said. “You can bet we will see this one being used to steal users’ Quicken data, database files, etc.

Steve Manzuik, a security product manager at eEye Digital Security, agreed. “This definitely looks like a flaw in IE and not a Google bug. He is using Google Desktop as to retrieve data, but it is IE that makes it possible” he said.

While IE is vulnerable, Gillon found that Firefox and Opera are not. For protection, Internet users could use one of those browsers or disable JavaScript in IE, Gillon suggested.

It has been a busy week on the Microsoft security front. Four examples of attack code were released for flaws in the Windows operating system, and a Trojan horse is finding its way onto PCs through another yet-unpatched flaw in IE.

From an article on News.com.

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