Most wireless devices use one of two technologies to avoid interference. What are these technologies?
What will be an ideal response?
ANSWER: The two technologies used are as follows:
* FHSS (frequency hopping spread spectrum)-Short bursts of data are transmitted on a particular frequency within the band and the next burst goes to the next frequency in the sequence. Frequency hopping can happen hundreds of times a second. FHSS is cheaper to implement than DSSS and performs better than DSSS in crowded, indoor environments.
* DSSS (direct sequence spread spectrum)-Data streams are divided and encoded into small chunks, called chips, which are spread over all available frequencies within one of three, wide channels, all at the same time. The process of dividing and encoding the data is called chipping, and the spreading ratio used to transform the data is called the chipping code, which is unique to each device. DSSS uses the available bandwidth more efficiently than FHSS and tends to have a higher throughput.
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Consider the algorithm for consensus in a synchronous system, which uses the following integrity definition: if all processes, whether correct or not, proposed the same value, then any correct process in the decided state would chose that value. Now consider an application in which correct processes may propose different results, e.g., by running different algorithms to decide which action to take in a control system’s operation. Suggest an appropriate modification to the integrity definition and thus to the algorithm.
What will be an ideal response?
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FarmVille is an example of a Facebook ________
Fill in the blank(s) with correct word