1. Compare and contrast analog and digital signals. 2. What is duplex communicat
ID: 3649311 • Letter: 1
Question
1. Compare and contrast analog and digital signals.2. What is duplex communication?
3. What is attenuation?
4. What is latency?
5. What is noise?
6. What is the relationship between throughput and bandwidth?
7. What's the difference between baseband and broadband?
8. Describe coaxial cable, STP, UTP, and fiber-optic cable.
9. Which media (coaxial, STP, UTP, and fiber-optic) do you think would give the most value for the cost for networking computers to create a LAN? Explain not only why your choice would be best, but what would be wrong with using the others.
10. What is a best practice for cable installation that will help prevent crosstalk and data errors and explain why it would useful for that purpose.
11. What serial data transmission method was codified by the EIA/TIA?
Explanation / Answer
1.Compare and contrast analog and digital signals. ans:analog data: Data represented in a continuous form, as contrasted with digital data having discrete values. Data that is recorded in a form that is similar to its original structure. Contrast with digital data. Analog signal: (electronics) A nominally continuous electrical signal that varies in amplitude or frequency in response to changes in sound, light, heat, position, or pressure. A signal in which some feature increases and decreases in the same way as the thing being transmitted. In am radio, for example, the strength of the radio wave goes up and down in analogy with the loudness of the original sound. (Contrast digital signal.)Radio, TV, some telephones, and tape recorders all use analog signals now, but the trend for the future is to send signals in digital form. An analog or analogue signal is any continuous signal for which the time varying feature (variable) of the signal is a representation of some other time varying quantity, i.e analogous to another time varying signal. It differs from a digital signal in that small fluctuations in the signal are meaningful. Analog is usually thought of in an electrical context; however, mechanical, pneumatic, hydraulic, and other systems may also convey analog signals. Essentially an analogue signal can be thought of as a simulation or duplication of one continuous time varying quantity in another, possibly different, time varying quantity. It is then a mapping of one time varying quantity to another, often with the intent of recording or transmitting information about the former within the medium of the latter. An analog signal uses some property of the medium to convey the signal's information. For example, an aneroid barometer uses rotary position as the signal to convey pressure information. Electrically, the property most commonly used is voltage followed closely by frequency, current, and charge. Digital data:. A digital system uses discrete (discontinuous) values, usually but not always symbolized numerically (hence called "digital") to represent information for input, processing, transmission, storage, etc. By contrast, non-digital (or analog) systems use a continuous range of values to represent information. Although digital representations are discrete, the information represented can be either discrete, such as numbers, letters or icons, or continuous, such as sounds, images, and other measurements of continuous systems. The word digital comes from the same source as the word digit and digitus (the Latin word for finger), as fingers are used for discrete counting. Digital signal: A signal in which the original information is converted into a string of bits before being transmitted. A radio signal, for example, will be either on or off. Digital signals can be sent for long distances and suffer less interference than Analog signals. The communications industry worldwide is in the midst of a switch to digital signals.Sound storage in a compact disk is in digital form. 2. What is duplex communication? Ans: 3 down vote accepted Duplex mode communication means two way communication. Normally in WCF the client calls the server. But there is no way for the server to call the client, e.g. to notify a chat client that there is a new chat message available. With a duplex contract the server provides an interface that the client has to implement. Now there are two interfaces one that the server implements as usual and one that the client implements. This enables the server to call methods on the client. In a chat program scenario this enables the server to notify the client when a new message is available, instead of the client having to constantly check with the server if there is something new. 3. What is attenuation? Ans: Attenuation is the reduction in intensity of a number of different things. It is the opposite of amplification. In physics or electronics the change is usually referred to using decibels (dB), noting the number of decibels by which a particular signal is reduced as it passes through a particular medium a certain distance. This concept is used quite a bit in the telecom industry because of its importance in determining where a repeater is needed. 4. What is latency? Ans.Network latency in a packet-switched network is measured either one-way (the time from the source sending a packet to the destination receiving it), or round-trip (the one-way latency from source to destination plus the one-way latency from the destination back to the source). Round-trip latency is more often quoted, because it can be measured from a single point. Note that round trip latency excludes the amount of time that a destination system spends processing the packet. Many software platforms provide a service called ping that can be used to measure round-trip latency. Ping performs no packet processing; it merely sends a response back when it receives a packet (i.e. performs a no-op), thus it is a relatively accurate way of measuring latency. Where precision is important, one-way latency for a link can be more strictly defined as the time from the start of packet transmission to the start of packet reception 5.what is noise? Ans:In communications, interference (static) that destroys the integrity of signals on a line. Noise can come from a variety of sources, including radio waves, nearby electrical wires, lightning, and bad connections. One of the major advantages of fiber optic cables over metal cables is that they are much less susceptible to noise 6.What is the relationship between throughput and bandwidth? Ans:Basically bandwidth is the maximum speed in which data can move over a medium. Think of bandwidth as a highway with 4 lanes in each direction. This is the "potential" amount of space you can fit cars in using the highway. Throughput is the actual speed in which data is moving over a medium. Think of throughput as the actual # cars on that highway. Although the highway can handle let's say 10,000 cars at once, at any given time the highway may only contain 2,000 cars, but the potential is always there for it to handle 10,000 cars. 7. What's the difference between baseband and broadband? Ans:In a baseband transmission, the entire bandwidth of the cable is consumed by a single signal. In broadband transmission, signals are sent on multiple frequencies, allowing multiple signals to be sent simultaneously. Baseband refers to a message signal that is transmitted and broadband refers to send the message to every one who is having a receiver. Baseband can carry both analog and digital signal where as broadband carries analog signal. Baseband is like point to point communication and broadband to is point to multi-point communication. Baseband will carry single signal in a medium but broadband can carry multisignals through single medium with shared bandwidth Also Baseband Signalling: 1)Uses digital signalling 2)Bi-directional transmission 3)No frequency-division multiplexing 4)Signal travels over short distances Broadband Signalling: 1)Uses analog signalling 2)Unidirectional transmission 3)Frequency-division multiplexing is possible 8.8. Describe coaxial cable, STP, UTP, and fiber-optic cable. Ans:Coaxial Cable
Related Questions
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.