Wireless Wide Area Network A WWAN differs from a WLAN (wireless LAN) in that it uses Mobile telecommunication cellular network technologies such as WIMAX (though it's better applicated into WMAN Networks), UMTS, GPRS, CDMA2000, GSM, CDPD, Mobitex, HSDPA or 3G to transfer data. It can use also LMDS and Wi-Fi to connect to the Internet. These cellular technologies are offered regionally, nationwide, or even globally and are provided by a wireless service provider for a monthly usage fee.[1] WWAN connectivity allows a user with a laptop and a WWAN card to surf the web, check email, or connect to a Virtual Private Network (VPN) from anywhere within the regional boundaries of cellular service. Various computers now have integrated WWAN capabilities (Such as HSDPA in Centrino). This means that the system has a cellular radio (GSM/CDMA) built in, which allows the user to send and receive data. There are two basic means that a mobile network may use to transfer data:
Packet-switched Data Networks (GPRS/CDPD)
Circuit-switched dial-up connections
Since radio communications systems do not provide a physically secure connection path, WWANs typically incorporate encryption and authentication methods to make them more secure. Unfortunately some of the early GSM encryption techniques were flawed, and security experts have issued warnings that cellular communication, including WWANs, is no longer secure.[2] UMTS(3G) encryption was developed later and has yet to be broken.
Examples of providers for WWAN include Sprint Nextel, Verizon, and AT&T.
Friday, December 5, 2008
Linksys WMP300N Wireless N PCI Network Adpater
Highlights
High-speed Wireless-N (draft 802.11n) networking for your desktop computer
MIMO technology uses multiple radios to create a robust signal that travel far and reduces dead spots
Can connect to Wireless-G and -B networks
Enhanced wireless security with Wi-Fi Protected Access™ (WPA2) with up to 256-bit encryption
Overview
Enjoy high-speed networking without wires with the Linksys® WMP300N Wireless-N PCI Adapter. The Wireless-N PCI Adapter installs in most desktop and tower PCs, and lets you put your computer almost anywhere in the building without the hassle of running network cables. You don't have to drill holes in your walls and climb through the attic or cellar to get connected to the network. Using the wireless networking technology, Wireless-N (draft 802.11n), the card delivers enhanced speed of up to 270 Mbps. By overlaying the signals of two Wireless-N compatible radios, the 'Multiple In, Multiple Out' (MIMO) technology effectively increases the data rate. MIMO uses signal reflections to increase the range and reduce 'dead spots' in the wireless coverage area. The robust signal travels farther, maintaining wireless connections. To protect your data and privacy, the card uses 256-bit WEP encryption besides WPA and WPA2 security.
High-speed Wireless-N (draft 802.11n) networking for your desktop computer
MIMO technology uses multiple radios to create a robust signal that travel far and reduces dead spots
Can connect to Wireless-G and -B networks
Enhanced wireless security with Wi-Fi Protected Access™ (WPA2) with up to 256-bit encryption
Overview
Enjoy high-speed networking without wires with the Linksys® WMP300N Wireless-N PCI Adapter. The Wireless-N PCI Adapter installs in most desktop and tower PCs, and lets you put your computer almost anywhere in the building without the hassle of running network cables. You don't have to drill holes in your walls and climb through the attic or cellar to get connected to the network. Using the wireless networking technology, Wireless-N (draft 802.11n), the card delivers enhanced speed of up to 270 Mbps. By overlaying the signals of two Wireless-N compatible radios, the 'Multiple In, Multiple Out' (MIMO) technology effectively increases the data rate. MIMO uses signal reflections to increase the range and reduce 'dead spots' in the wireless coverage area. The robust signal travels farther, maintaining wireless connections. To protect your data and privacy, the card uses 256-bit WEP encryption besides WPA and WPA2 security.
National Television System Committee
The National Television System Committee was established in 1940 by the United States Federal Communications Commission (FCC) to resolve the conflicts that arose between companies over the introduction of a nationwide analog television system in the United States. In March 1941, the committee issued a technical standard for black-and-white television that built upon a 1936 recommendation made by the Radio Manufacturers Association (RMA). Technical advancements of the vestigial sideband technique allowed for the opportunity to increase the image resolution broadcast to consumer televisions. The NTSC compromised between RCA's desire to keep a 441–scan line standard (which was already being used by RCA's NBC TV network) and Philco's desire to increase the number of scan lines to between 605 and 800: A 525-line transmission standard was selected. Other technical standards in the final recommendation were a frame rate (image rate) of 30 frames per second consisting of two interlaced fields per frame (2:1 interlacing) at 262.5 lines per field or 60 fields per second, along with an aspect ratio of 4:3, and frequency modulation (FM) for the sound signal (which was quite new at the time).
In January 1950 the Committee was reconstituted to standardize color television. In December 1953, it unanimously approved what is now called simply the NTSC color television standard (later defined as RS-170a). The updated standard retained full backwards compatibility ("compatible color") with older black-and-white television sets. Color information was added to the black-and-white image by adding a color subcarrier of 4.5 × 455/572 MHz (approximately 3.58 MHz) to the video signal. In order to minimize interference between the chrominance signal and FM sound carrier, the addition of the color subcarrier also required a slight reduction of the frame rate from 30 frames per second to 30/1.001 (very close to 29.97) frames per second, and changing the line frequency from 15,750 Hz to 15,734.26 Hz.
The FCC had briefly approved a different color television standard, starting in October 1950, which was developed by CBS.[2] However, this standard was incompatible with black-and-white broadcasts. It used a rotating color wheel (a technique re-used in the first DLP projectors developed in the late 1980s), reduced the number of scan lines from 525 to 405, and increased the field rate from 60 to 144 (but had an effective frame rate of only 24 frames a second). Legal action by rival RCA kept commercial use of the system off the air until June 1951, and regular broadcasts only lasted a few months before manufacture of all color television sets was banned by the Office of Defense Mobilization (ODM) in October, ostensibly due to the Korean War.[3] CBS rescinded its system in March 1953,[4] and the FCC replaced it on December 17, 1953 with the NTSC color standard, which was cooperatively developed by several companies (including RCA and Philco).[5] The first publicly announced network TV broadcast of a program using the NTSC "compatible color" system was an episode of NBC's Kukla, Fran and Ollie on August 30, 1953, although it was viewable in color only at the network's headquarters.[6] The first nationwide view of NTSC color came on the following January 1 with the coast-to-coast broadcast of the Tournament of Roses Parade, viewable on prototype color receivers at special presentations across the country.
The first color NTSC television camera was the RCA TK-40, used for experimental broadcasts in 1953; an improved version, the TK-40A, introduced in March 1954, was the first commercially available color TV camera. It was replaced later that year by an improved version, the TK-41, which became the standard camera used throughout much of the 1960s.
The NTSC standard has been adopted by other countries, including most of the Americas and Japan. With the advent of digital television, analog broadcasts are being phased out. Most NTSC broadcasters are mandated by the FCC to shut down in the United States on February 17, 2009 (low power, class A and translators are not immediately affected. A cut-off date for those stations is to be determined).
In January 1950 the Committee was reconstituted to standardize color television. In December 1953, it unanimously approved what is now called simply the NTSC color television standard (later defined as RS-170a). The updated standard retained full backwards compatibility ("compatible color") with older black-and-white television sets. Color information was added to the black-and-white image by adding a color subcarrier of 4.5 × 455/572 MHz (approximately 3.58 MHz) to the video signal. In order to minimize interference between the chrominance signal and FM sound carrier, the addition of the color subcarrier also required a slight reduction of the frame rate from 30 frames per second to 30/1.001 (very close to 29.97) frames per second, and changing the line frequency from 15,750 Hz to 15,734.26 Hz.
The FCC had briefly approved a different color television standard, starting in October 1950, which was developed by CBS.[2] However, this standard was incompatible with black-and-white broadcasts. It used a rotating color wheel (a technique re-used in the first DLP projectors developed in the late 1980s), reduced the number of scan lines from 525 to 405, and increased the field rate from 60 to 144 (but had an effective frame rate of only 24 frames a second). Legal action by rival RCA kept commercial use of the system off the air until June 1951, and regular broadcasts only lasted a few months before manufacture of all color television sets was banned by the Office of Defense Mobilization (ODM) in October, ostensibly due to the Korean War.[3] CBS rescinded its system in March 1953,[4] and the FCC replaced it on December 17, 1953 with the NTSC color standard, which was cooperatively developed by several companies (including RCA and Philco).[5] The first publicly announced network TV broadcast of a program using the NTSC "compatible color" system was an episode of NBC's Kukla, Fran and Ollie on August 30, 1953, although it was viewable in color only at the network's headquarters.[6] The first nationwide view of NTSC color came on the following January 1 with the coast-to-coast broadcast of the Tournament of Roses Parade, viewable on prototype color receivers at special presentations across the country.
The first color NTSC television camera was the RCA TK-40, used for experimental broadcasts in 1953; an improved version, the TK-40A, introduced in March 1954, was the first commercially available color TV camera. It was replaced later that year by an improved version, the TK-41, which became the standard camera used throughout much of the 1960s.
The NTSC standard has been adopted by other countries, including most of the Americas and Japan. With the advent of digital television, analog broadcasts are being phased out. Most NTSC broadcasters are mandated by the FCC to shut down in the United States on February 17, 2009 (low power, class A and translators are not immediately affected. A cut-off date for those stations is to be determined).
Astro (Satellite TV)
Astro (Satellite TV)
Astro is a subscription-based direct broadcast satellite (DBS) or direct-to-home satellite television and radio service initially in Malaysia, but has expanded to Brunei and Indonesia. The service is broadcast from the All Asia Broadcast Centre (ABC) located in Bukit Jalil, Kuala Lumpur, Malaysia. Astro is owned by MEASAT Broadcast Network Systems, a subsidiary of Astro All Asia Networks plc.
Astro is a subscription-based direct broadcast satellite (DBS) or direct-to-home satellite television and radio service initially in Malaysia, but has expanded to Brunei and Indonesia. The service is broadcast from the All Asia Broadcast Centre (ABC) located in Bukit Jalil, Kuala Lumpur, Malaysia. Astro is owned by MEASAT Broadcast Network Systems, a subsidiary of Astro All Asia Networks plc.
Thursday, December 4, 2008
Wireless LAN
A wireless LAN or WLAN or wireless local area network is the linking of two or more computers or devices using spread-spectrum or OFDM modulation technology based to enable communication between devices in a limited area. This gives users the mobility to move around within a broad coverage area and still be connected to the network.
For the home user, wireless has become popular due to ease of installation, and location freedom with the gaining popularity of laptops. Public businesses such as coffee shops or malls have begun to offer wireless access to their customers; some are even provided as a free service. Large wireless network projects are being put up in many major cities. Google is even providing a free service to Mountain View, California[1] and has entered a bid to do the same for San Francisco.[2] New York City has also begun a pilot program to cover all five boroughs of the city with wireless Internet access
For the home user, wireless has become popular due to ease of installation, and location freedom with the gaining popularity of laptops. Public businesses such as coffee shops or malls have begun to offer wireless access to their customers; some are even provided as a free service. Large wireless network projects are being put up in many major cities. Google is even providing a free service to Mountain View, California[1] and has entered a bid to do the same for San Francisco.[2] New York City has also begun a pilot program to cover all five boroughs of the city with wireless Internet access
WiMAX
WiMAX, meaning Worldwide Interoperability for Microwave Access, is a telecommunications technology that provides for the wireless transmission of data using a variety of transmission modes, from point-to-point links to portable internet access[citation needed]. The technology provides up to 75 Mb/sec symmetric broadband speed without the need for cables. The technology is based on the IEEE 802.16 standard (also called Broadband Wireless Access). The name "WiMAX" was created by the WiMAX Forum, which was formed in June 2001 to promote conformity and interoperability of the standard. The forum describes WiMAX as "a standards-based technology enabling the delivery of last mile wireless broadband access as an alternative to cable and DSL".
CDMA2000
CDMA2000 is a hybrid 2.5G / 3G technology of mobile telecommunications standards that use CDMA, a multiple access scheme for digital radio, to send voice, data, and signalling data (such as a dialed telephone number) between mobile phones and cell sites. CDMA2000 is considered a 2.5G technology in 1xRTT and a 3G technology in EVDO.
CDMA (code division multiple access) is a mobile digital radio technology where channels are defined with codes (PN sequences). CDMA permits many simultaneous transmitters on the same frequency channel, unlike TDMA (time division multiple access), used in GSM and D-AMPS, and FDMA, used in AMPS ("analog" cellular). Since more phones can be served by fewer cell sites, CDMA-based standards have a significant economic advantage over TDMA- or FDMA-based standards.
CDMA2000 has a relatively long technical history, and remains compatible with the older CDMA telephony methods (such as cdmaOne) first developed by Qualcomm, a commercial company, and holder of several key international patents on the technology.
The CDMA2000 standards CDMA2000 1xRTT, CDMA2000 EV-DO, and CDMA2000 EV-DV are approved radio interfaces for the ITU's IMT-2000 standard and a direct successor to 2G CDMA, IS-95 (cdmaOne). CDMA2000 is standardized by 3GPP2.
CDMA2000 is a registered trademark of the Telecommunications Industry Association (TIA-USA) in the United States, not a generic term like CDMA. (This is similar to how TIA has branded their 2G CDMA standard, IS-95, as cdmaOne.)
CDMA2000 is an incompatible competitor of the other major 3G standard UMTS. It is defined to operate at 450 MHz, 700 MHz, 800 MHz, 900 MHz, 1700 MHz, 1800 MHz, 1900 MHz, and 2100 MHz.
Below are the different types of CDMA2000, in order of increasing complexity:
CDMA (code division multiple access) is a mobile digital radio technology where channels are defined with codes (PN sequences). CDMA permits many simultaneous transmitters on the same frequency channel, unlike TDMA (time division multiple access), used in GSM and D-AMPS, and FDMA, used in AMPS ("analog" cellular). Since more phones can be served by fewer cell sites, CDMA-based standards have a significant economic advantage over TDMA- or FDMA-based standards.
CDMA2000 has a relatively long technical history, and remains compatible with the older CDMA telephony methods (such as cdmaOne) first developed by Qualcomm, a commercial company, and holder of several key international patents on the technology.
The CDMA2000 standards CDMA2000 1xRTT, CDMA2000 EV-DO, and CDMA2000 EV-DV are approved radio interfaces for the ITU's IMT-2000 standard and a direct successor to 2G CDMA, IS-95 (cdmaOne). CDMA2000 is standardized by 3GPP2.
CDMA2000 is a registered trademark of the Telecommunications Industry Association (TIA-USA) in the United States, not a generic term like CDMA. (This is similar to how TIA has branded their 2G CDMA standard, IS-95, as cdmaOne.)
CDMA2000 is an incompatible competitor of the other major 3G standard UMTS. It is defined to operate at 450 MHz, 700 MHz, 800 MHz, 900 MHz, 1700 MHz, 1800 MHz, 1900 MHz, and 2100 MHz.
Below are the different types of CDMA2000, in order of increasing complexity:
Tuesday, December 2, 2008
Wireless Support
Wireless Support
At this moment only the RT25USB-SRC-V2.0.7.0 driver from Ralink is succesfully ported and reported to be working with an ASUS WL-167G USB dongle on 2.6.5-it0. This tutorial gives enough information to easily use the ASUS WL-167G on your OSD, but also gives enough information for everyone who wants to port another driver.
So what do you need:
* kernel 2.6.5-it0 with wireless extensions enabled, this is due to the broken USB Host driver in 2.6.15 (instructions below)
* dongle with RT2570 chipset, see serialmonkey for a list
* the source code of the dongle driver. I've succesfully 'ported' the RT25USB-SRC-V2.0.7.0 driver from Ralink
* and some version of wireless tools to send commands to the dongle, available here
* wireless support has only been tested with the developer OSD (green PCB). If you have the yellow/orange one shipped from thinkgeek then you could be the first to get wireless working on a BETA sample!
The broken USB Host driver is expected to be fixed by the manufacturer around 9/12. Until this time you will have to downgrade your OSD to a 2.6.5 kernel... and probably has the consequence that you can't play any video/audio :P
At this moment only the RT25USB-SRC-V2.0.7.0 driver from Ralink is succesfully ported and reported to be working with an ASUS WL-167G USB dongle on 2.6.5-it0. This tutorial gives enough information to easily use the ASUS WL-167G on your OSD, but also gives enough information for everyone who wants to port another driver.
So what do you need:
* kernel 2.6.5-it0 with wireless extensions enabled, this is due to the broken USB Host driver in 2.6.15 (instructions below)
* dongle with RT2570 chipset, see serialmonkey for a list
* the source code of the dongle driver. I've succesfully 'ported' the RT25USB-SRC-V2.0.7.0 driver from Ralink
* and some version of wireless tools to send commands to the dongle, available here
* wireless support has only been tested with the developer OSD (green PCB). If you have the yellow/orange one shipped from thinkgeek then you could be the first to get wireless working on a BETA sample!
The broken USB Host driver is expected to be fixed by the manufacturer around 9/12. Until this time you will have to downgrade your OSD to a 2.6.5 kernel... and probably has the consequence that you can't play any video/audio :P
WLAN WI-FI Solutions
* TrangoLINK Giga® is a split-architecture (ODU/IDU) full duplex RF microwave system link that is both native Ethernet and native-TDM.
* TrangoLINK® Apex is an all-outdoor full duplex RF microwave radio that is native-Ethernet for 100% IP traffic.
* ATLAS 4900™ is an all-outdoor native Ethernet OFDM 4.9 GHz wireless bridge that operates in the licensed Public Safety band.
Unlicensed Point-to-Point Wireless WAN Radios
* TrangoLINK-45™ is an all-outdoor, native Ethernet, multi-band OFDM wireless Ethernet bridge that is capable of operation in 4 different 5 GHz bands (5.2, 5.3, 5.4, 5.8 GHz).
* TrangoLINK-10™ is an all-outdoor, native Ethernet 5.8 GHz wireless bridge.
Unlicensed Point-to-MultiPoint Wireless WAN Radios
For delivering point-to-multipoint (PtMP) broadband access wireless WAN connectivity from a central office to many remote offices, Trango offers these robust solutions.
* Access5830™ System 5.8 GHz broadband wireless access system delivers up to 10 Mbps up to 18 miles.
* Trango M2400S™ 2.4 GHz broadband wireless access system delivers up to 5 Mbps up to 25 miles.
* Trango M900S™ 900 MHz broadband wireless access system delivers up to 3 Mbps up to 20 miles.
* TrangoLINK® Apex is an all-outdoor full duplex RF microwave radio that is native-Ethernet for 100% IP traffic.
* ATLAS 4900™ is an all-outdoor native Ethernet OFDM 4.9 GHz wireless bridge that operates in the licensed Public Safety band.
Unlicensed Point-to-Point Wireless WAN Radios
* TrangoLINK-45™ is an all-outdoor, native Ethernet, multi-band OFDM wireless Ethernet bridge that is capable of operation in 4 different 5 GHz bands (5.2, 5.3, 5.4, 5.8 GHz).
* TrangoLINK-10™ is an all-outdoor, native Ethernet 5.8 GHz wireless bridge.
Unlicensed Point-to-MultiPoint Wireless WAN Radios
For delivering point-to-multipoint (PtMP) broadband access wireless WAN connectivity from a central office to many remote offices, Trango offers these robust solutions.
* Access5830™ System 5.8 GHz broadband wireless access system delivers up to 10 Mbps up to 18 miles.
* Trango M2400S™ 2.4 GHz broadband wireless access system delivers up to 5 Mbps up to 25 miles.
* Trango M900S™ 900 MHz broadband wireless access system delivers up to 3 Mbps up to 20 miles.
Wireless WAN Solutions
Extend your network infrastructure with long range
outdoor wireless Ethernet connections
Trango's long range fixed wireless broadband Ethernet equipment is ideal for all types of wireless wide area network (WWAN) and wireless local area network (WLAN) applications. Trango outdoor wireless networking solutions allow you to quickly, easily, and cost effectively deploy reliable, high-speed, secure wireless IP connections between multiple remote locations at distances up to 45+ miles, and enable you to eliminate your costly leased lines and avoid expensive time consuming fiber trenching.
Wireless WAN Applications
Wireless WAN applications are endless for Trango long-range wireless Ethernet bridges. For example, a business may need to link its IT infrastructure to a few outlying buildings; a university or any school may need to provide internet access to dormitories or other buildings across campus; or a hospital may need to establish a secure link to a clinic across town so that doctors may securely exchange patient information over a high-speed connection.
Whether you need to a network connection across the street, across town, or from urban to rural areas, Trango wireless WAN/LAN building-to-building outdoor networks are ideal for any private enterprise or network operator that requires high-speed connectivity between two or more remote locations. Trango long range wireless wide area network (WWAN) solutions are well suited for a wide variety of industries and applications because they deliver high-capacity bandwidth, are extremely reliable, highly secure, and can be established with minimal effort and cost.
Licensed Point-to-Point Wireless WAN Radios
* TrangoLINK Giga® is a split-architecture (ODU/IDU) full duplex RF microwave system link that is both native Ethernet and native-TDM.
* TrangoLINK® Apex is an all-outdoor full duplex RF microwave radio that is native-Ethernet for 100% IP traffic.
* ATLAS 4900™ is an all-outdoor native Ethernet OFDM 4.9 GHz wireless bridge that operates in the licensed Public Safety band.
Unlicensed Point-to-Point Wireless WAN Radios
* TrangoLINK-45™ is an all-outdoor, native Ethernet, multi-band OFDM wireless Ethernet bridge that is capable of operation in 4 different 5 GHz bands (5.2, 5.3, 5.4, 5.8 GHz).
* TrangoLINK-10™ is an all-outdoor, native Ethernet 5.8 GHz wireless bridge.
Unlicensed Point-to-MultiPoint Wireless WAN Radios
For delivering point-to-multipoint (PtMP) broadband access wireless WAN connectivity from a central office to many remote offices, Trango offers these robust solutions.
* Access5830™ System 5.8 GHz broadband wireless access system delivers up to 10 Mbps up to 18 miles.
* Trango M2400S™ 2.4 GHz broadband wireless access system delivers up to 5 Mbps up to 25 miles.
* Trango M900S™ 900 MHz broadband wireless access system delivers up to 3 Mbps up to 20 miles.
outdoor wireless Ethernet connections
Trango's long range fixed wireless broadband Ethernet equipment is ideal for all types of wireless wide area network (WWAN) and wireless local area network (WLAN) applications. Trango outdoor wireless networking solutions allow you to quickly, easily, and cost effectively deploy reliable, high-speed, secure wireless IP connections between multiple remote locations at distances up to 45+ miles, and enable you to eliminate your costly leased lines and avoid expensive time consuming fiber trenching.
Wireless WAN Applications
Wireless WAN applications are endless for Trango long-range wireless Ethernet bridges. For example, a business may need to link its IT infrastructure to a few outlying buildings; a university or any school may need to provide internet access to dormitories or other buildings across campus; or a hospital may need to establish a secure link to a clinic across town so that doctors may securely exchange patient information over a high-speed connection.
Whether you need to a network connection across the street, across town, or from urban to rural areas, Trango wireless WAN/LAN building-to-building outdoor networks are ideal for any private enterprise or network operator that requires high-speed connectivity between two or more remote locations. Trango long range wireless wide area network (WWAN) solutions are well suited for a wide variety of industries and applications because they deliver high-capacity bandwidth, are extremely reliable, highly secure, and can be established with minimal effort and cost.
Licensed Point-to-Point Wireless WAN Radios
* TrangoLINK Giga® is a split-architecture (ODU/IDU) full duplex RF microwave system link that is both native Ethernet and native-TDM.
* TrangoLINK® Apex is an all-outdoor full duplex RF microwave radio that is native-Ethernet for 100% IP traffic.
* ATLAS 4900™ is an all-outdoor native Ethernet OFDM 4.9 GHz wireless bridge that operates in the licensed Public Safety band.
Unlicensed Point-to-Point Wireless WAN Radios
* TrangoLINK-45™ is an all-outdoor, native Ethernet, multi-band OFDM wireless Ethernet bridge that is capable of operation in 4 different 5 GHz bands (5.2, 5.3, 5.4, 5.8 GHz).
* TrangoLINK-10™ is an all-outdoor, native Ethernet 5.8 GHz wireless bridge.
Unlicensed Point-to-MultiPoint Wireless WAN Radios
For delivering point-to-multipoint (PtMP) broadband access wireless WAN connectivity from a central office to many remote offices, Trango offers these robust solutions.
* Access5830™ System 5.8 GHz broadband wireless access system delivers up to 10 Mbps up to 18 miles.
* Trango M2400S™ 2.4 GHz broadband wireless access system delivers up to 5 Mbps up to 25 miles.
* Trango M900S™ 900 MHz broadband wireless access system delivers up to 3 Mbps up to 20 miles.
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