QUIZ 1 - IS 410 QUESTIONS WELL ANSWERED LATEST UPDATE 2026

QUIZ 1 - IS 410 QUESTIONS WELL ANSWERED LATEST UPDATE 2026 Layered approach - Answers physical infrastructure - Network protocols & commun. software - Applications Analog signal - Answers continuously varying (we live in an analog world) analog data examples: light, voice, video -Our sensations of pictures, sounds etc. are analog Frequency: - Answers Number of seconds per cycle -Analog signals have continuously repeating waveforms Hertz (Hz) - Answers Cycles per second 1 Khz - 1000 Hz 1 Mhz - 1000 Khz 1 Ghz - 1000 Mhz Digital Signals - Answers -Discrete or quantized -Used for processing, storage, and transmission Sampling - Answers -analog is sampled at regular intervals to generate a digital signal, which approximates the the analog waveform -original analog info may be recovered from the digital signal Digital convergence - Answers Access to data, voice and video through single, digital user interface. advantages of digital tech - Answers -VLSI and the cost of digital circuitry -Error Correction and Control: A digital signal, since it is a pattern of bits, can be checked for errors, and the original signal may be regenerated. -Data integrity and reliability in transmission: Less susceptible to noise, as original signal can be recovered from distorted signal. -Capacity utilization: digital signals are easier to multiplex over high bandwidth channels -Integration of voice, video and data -Security and privacy: encryption of digital data -Compression: digital signals can be easily compressed, allowing transmission of large amounts of information over limited bandwidth. Bit - Answers -Binary digit: value 0 or 1 -Bits per second (bps) or bit rate describes transmission speed. The higher the bps, the shorter the duration of each individual bit. Increasing units for speed: -kilobits per second(kbps) -Megabits per second Mbps -Gigabits per second Gbps -Terabits per second Tbps -Note: computer memory is usually referred to in bytes, kilobytes,megabytes, gigabytes etc. Transmission speed is referred to in bits per second. A byte, is eight bits. Channel Bandwidth - Answers Highest-lowest frequency allowed by the channel -An analog measure Data rate - Answers -bit rate, used to specify digital transmission. --For a given medium, as bandwidth goes up, data rate goes up as well. -The data rate for a given medium depends on its bandwidth, and the extent of distortions-noise- induced by it into the signal] -E.g., local telephone lines have a bandwidth of 3100 Hz (3400 - 300) for analog signals. This leads to an effective maximum of 35 kbps for transmission through modems. Modulation - Answers Process of imprinting the communication signal onto a carrier signal, which is better suited for the communication medium. The communication signal rides piggyback on a 'carrier' signal. Modems - Answers acronym for modulator/demodulator - Digital to analog and vice versa -Modem standards: sponsored, negotiated and maintained by ITU. PCM - Pulse Code Modulation - Answers -is the most common method for transmitting long-distance telephone calls in digital form. -For voice digitization, 8000 samples of an analog signal are taken per sec. Why 8000 samples? Consider the 3100 Hz bandwidth of the telephone channel. Theoretically, we need to take at least twice as many samples per second as the allowable bandwidth of a channel. For practical reasons, 8000 samples are taken. -Each sample is rounded and converted to the nearest 8-bit binary number. With 8 bits and 8000 samples per second, the rate is 8 * 8000 = 64 kbps. Local Loop - Answers The lines connecting small home and office (SOHO) users to nearest network service provider switch.[for telephone networks, this would be the telephone company switch.] For the telephone local loop, Transmission is analog, and bandwidth is 3100 Hz. Maximum data rate is 35 kbps.