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ARPAnet is a wide area network(WAN)．A network that connected Department of Defense research sites across(1)．Created in 1 969 with funding from the Advanced Research Projects Agency(ARPA)．Undergoing constant research and development in the early—to mid一1970s，ARPAnet(2)aS the test bed for the development of(3)(the protocols that make the Internet possible)．A major goal of the ARPAnet project was to increase the military’s command and control capability by enabling communication across a variety of physically (4)media，including satellites．An allied goal was to create a robust network：(5)withstanding outages，such as those that might result from a nuclear exchange．ARPAnet met these objectives，but it also (6) its creators：It was found in short order that most ARPAnet users (7) use the network for(8)，such as electronic mail and discussion groups．Initially，the ARPAnet was available only to government research institutes and to universities holding Department of Defense(DoD)research contracts．In 1 983，ARPAnet was(9)into a high—security military network(Milnet)and an ARPAnet that was recast as a research and development network．Although it formed the (10) of the Internet，it was decommissioned in 1 990． (10)
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ARPAnet is a wide area network(WAN)．A network that connected Department of Defense research sites across(1)．Created in 1 969 with funding from the Advanced Research Projects Agency(ARPA)．Undergoing constant research and development in the early—to mid一1970s，ARPAnet(2)aS the test bed for the development of(3)(the protocols that make the Internet possible)．A major goal of the ARPAnet project was to increase the military’s command and control capability by enabling communication across a variety of physically (4)media，including satellites．An allied goal was to create a robust network：(5)withstanding outages，such as those that might result from a nuclear exchange．ARPAnet met these objectives，but it also (6) its creators：It was found in short order that most ARPAnet users (7) use the network for(8)，such as electronic mail and discussion groups．Initially，the ARPAnet was available only to government research institutes and to universities holding Department of Defense(DoD)research contracts．In 1 983，ARPAnet was(9)into a high—security military network(Milnet)and an ARPAnet that was recast as a research and development network．Although it formed the (10) of the Internet，it was decommissioned in 1 990． (9)
ARPAnet is a wide area network(WAN)．A network that connected Department of Defense research sites across(1)．Created in 1 969 with funding from the Advanced Research Projects Agency(ARPA)．Undergoing constant research and development in the early—to mid一1970s，ARPAnet(2)aS the test bed for the development of(3)(the protocols that make the Internet possible)．A major goal of the ARPAnet project was to increase the military’s command and control capability by enabling communication across a variety of physically (4)media，including satellites．An allied goal was to create a robust network：(5)withstanding outages，such as those that might result from a nuclear exchange．ARPAnet met these objectives，but it also (6) its creators：It was found in short order that most ARPAnet users (7) use the network for(8)，such as electronic mail and discussion groups．Initially，the ARPAnet was available only to government research institutes and to universities holding Department of Defense(DoD)research contracts．In 1 983，ARPAnet was(9)into a high—security military network(Milnet)and an ARPAnet that was recast as a research and development network．Although it formed the (10) of the Internet，it was decommissioned in 1 990． (7)
ARPAnet is a wide area network(WAN)．A network that connected Department of Defense research sites across(1)．Created in 1 969 with funding from the Advanced Research Projects Agency(ARPA)．Undergoing constant research and development in the early—to mid一1970s，ARPAnet(2)aS the test bed for the development of(3)(the protocols that make the Internet possible)．A major goal of the ARPAnet project was to increase the military’s command and control capability by enabling communication across a variety of physically (4)media，including satellites．An allied goal was to create a robust network：(5)withstanding outages，such as those that might result from a nuclear exchange．ARPAnet met these objectives，but it also (6) its creators：It was found in short order that most ARPAnet users (7) use the network for(8)，such as electronic mail and discussion groups．Initially，the ARPAnet was available only to government research institutes and to universities holding Department of Defense(DoD)research contracts．In 1 983，ARPAnet was(9)into a high—security military network(Milnet)and an ARPAnet that was recast as a research and development network．Although it formed the (10) of the Internet，it was decommissioned in 1 990． (6)
Now a new high-rate extension to the standard，802．11b，lets(1)networks support data rates to 1 1 M bit／see．Ratified in 1997，the-original 802．11 standard united the wireless industry by defining a(2)protocol architecture that worked with conventional upper—layer (3)．Also，802．11 maintained compatibility with the three most popular radio transmission types： (4)spread spectrum，~equency-hopping spread spectrum，and infrared(5) ，this new architecture added (6)alt the medium access control(MAC)layer 2 and at the physical(PHY)(7) ，forcing(8)between the two layers in performing the critical tasks involved with initiating and maintaining wireless communications．For instance，to ensure(9)of the wireless link，MAC and PHY work together to determine if a，(10)path exists before they start a transmission． (9)
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