Exam 6: Data Communication and the Cloud

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A LAN is a group of computers connected together on a single company site.Usually the computers are located within a half mile or so of each other.The computers and other devices are connected via a switch, which is a special-purpose computer that receives and transmits messages on the LAN.
Each device on a LAN (computer, printer, etc.)has a hardware component called a network interface card (NIC)that connects the device's circuitry to network wires.The NIC works with programs in each device to implement the protocols necessary for communication.Most computers today ship from the factory with an onboard NIC, which is an NIC built into the computer's circuitry.
The computers, printers, switches, and other devices on a LAN are connected using one of two media.Most connections are made using unshielded twisted pair (UTP)cable.This cable contains sets of wires that are twisted together to improve signal quality.However, if the connection carries a lot of traffic, the UTP cable may be replaced by optical fiber cables.The signals on such cables are light rays, and they are reflected inside the glass core of the optical fiber cable.

Correct Answer:

Verified

We define the cloud as the elastic leasing of pooled computer resources over the Internet.The term elastic means that the amount of resources leased can be increased or decreased dynamically, programmatically, and in a short span of time and that organizations usually pay for just the resources that they use.The resources are pooled, because many different organizations use the same physical hardware; they share that hardware through virtualization.Cloud vendors dynamically allocate virtual machines to physical hardware as customer needs increase or decrease.Finally, the resources are accessed via Internet protocols and standards, which are additions to TCP/IP that enable cloud-hosting vendors to provide processing capabilities in flexible, yet standardized, ways.