Recent questions tagged csma-cd

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Which multiple access technique is used by $\text{IEEE } 802.11$ standard for wireless $\text{LAN}$ ? $\text{CDMA}$ $\text{CSMA/CA}$ $\text{ALOHA}$ None of the options
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In $3G$ network, $\text{W-CDMA}$ is also known as $\text{UMTS}$. The minimum spectrum allocation required for $\text{W-CDMA}$ is $2$ MHz $20$ KHz $5$ KHz $5$ MHz
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Write a program to simulate the behavior of the CSMA/CD protocol over Ethernet when there are N stations ready to transmit while a frame is being transmitted. Your program should report the times when each station successfully starts sending its frame. Assume that a ... μsec) and a collision detection and sending of a jamming sequence takes one slot time. All frames are the maximum length allowed.
4
Two CSMA/CD stations are each trying to transmit long (multiframe) files. After each frame is sent, they contend for the channel, using the binary exponential backoff algorithm. What is the probability that the contention ends on round k, and what is the mean number of rounds per contention period?
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A 1-km-long, 10-Mbps CSMA/CD LAN (not 802.3) has a propagation speed of 200 m/μsec. Repeaters are not allowed in this system. Data frames are 256 bits long, including 32 bits of header, checksum, and other overhead. The first bit slot after a ... the channel in order to send a 32-bit acknowledgement frame. What is the effective data rate, excluding overhead, assuming that there are no collisions?
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What is the length of a contention slot in CSMA/CD for (a) a 2-km twin-lead cable (signal propagation speed is 82% of the signal propagation speed in vacuum)?, and (b) a 40-km multimode fiber optic cable (signal propagation speed is 65% of the signal propagation speed in vacuum)?
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1 vote
8
A)340 bits B) 240bits
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A broadcast channel has 10 nodes and total capacity of 16Mbps. It uses polling for medium access. Once a node finishes transmission, there is a polling delay of 100 µseconds to poll the next node. Whenever a node is polled, it is allowed to transmit a maximum of 1500 Bytes. The maximum throughput of broadcast channel is: 8 Mbps 14 Mbps 100/11Mbps 750/85 Mbps
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Consider a 8Mbps token LAN with a ring latency of 256µsec. A host need to transmit seizes the token, and then it sends a frame of 1024 bytes removes the frame after it has circulated all around the ring and finally releases the token. This process is repeated for every frame. Assuming that only a single host wishes to transmit, then the effective data rate (in Mbps) is? 4.53 5.36 6.7 9.4
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A building running CSMA–CD protocol is having a bandwidth of 512Mbps and distance of 2 kilometres then determine the minimum data size in order to detect a collision. Assume that the signal speed is 2,00,000km/s 1000bytes 1250bytes 1280bytes 1024bytes
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Suppose that the one-way propagation delay for a 100 Mbps Ethernet having 48-bit jamming signal is 1.04 micro-seconds. The minimum frame size in bits is: 112 160 208 256
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If CSMA transmits 8 stations network data in single channel whats is the chip code for station 5 {Assume that W1=[+1]} how to solve it solution given is. 1111-1-1-1-1.
14
Consider two node A and B on the same ethernet segment and suppose the propagation delay between the node is 225-bit times. Suppose at the time both node A and B begin to transmit a frame. Assume both nodes transmit a 50-bit jam signal after detecting a collision. For 10^7 bits per sec ethernet, the time at which both nodes A and B sense an idle channel is __microsec
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In CSMA CD: 1) Before starting transmission of frame station sense COMPLETE carrier or only its connection point ? example : if D is transmitting frame to E WIll A sense carrier as idle or busy 2) Lets take At time t = 5 Station A wants to send frame ... wants to send frame to E . WIll it be possible simultaneously ? Does detecting channel idle by two stations ALWAYS imply collision will happen ?
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Suppose that a wireless link layer using a CSMA-like protocol backs off 1ms on average. A packet's link and physical layer headers are always set at the same bitrate and take a total of 125us to transmit. If a packet is sent with a link layer payload of 1000 ... packet time taken up by backoff and link/physical layer headers. Can someone help me out and explain the solution. I'm stuck here.
1 vote
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I was not convinced by the solution provided so, I made my own analysis. Given propagation delay is 225-bit times, and since bandwidth is $10^7 bps$, so my $T_p=22.5 \mu s$ Suppose at t=0, both A and B start to transmit. At t=$22.5 \mu s$, both A and B will detect a collision. ... by both A and B. Now, my question is whether at t=$51 \mu s$ my channel would look idle to A and B or at $50 \mu s$ ?
18
The round trip propagation delay for a 100Mbps Ethernet having 48-bit jamming signal is 64 ms. What is the minimum frame size (in bytes)?
1 vote
19
A local area network operates Ethernet with CSMA/CD mechanism and runs at a transmission rate of 8 Mbps and a one-way signal propagation time of 25 microseconds. How long has a station to wait before trying to access the channel again, after experiencing 5 successive collisions? 1. 125 microseconds. 2. 625 microseconds 3. 800 microseconds 4. 1600 microseconds.
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Assume that X and Y are the only two stations on an Ethernet. Each has a steady queue of frames to send. Both X and Y attempt to transmit a frame, they wait to get the control of channel using binary exponential algorithm. The probability that both were successfully ... on fifth round of the algorithm (assuming every time both X and Y will collide in back-off race till 4th round) is ________.
21
Consider CSMA/CD LAN with bandwidth 10 Mbps and propagation delay of 5 μsec. Repeaters are not allowed in this system. Data frames are 512 bits long, including 32 bits of header, checksum and other overhead. The first bit slot after a successful transmission is ... frame. The effective data rate of the network is ________ (in Mbps). (Excluding overhead, assuming that there are no collisions)
22
In standard ethernet with transmission rate of 20 Mbps, the length of the cables is 2500 m and the size of frame is 512 bits. The propagation speed of a signal in a cable is 2 × 108 m/s. The percentage of the time channel is idle or not used by a station is _________ (in approximate integer value).
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Consider CSMA/CD LAN with bandwidth 10 Mbps and propagation delay of 5 μsec. Repeaters are not allowed in this system. Data frames are 512 bits long, including 32 bits of header, checksum and other overhead. The first bit slot after a successful transmission is ... overhead, assuming that there are no collisions) (Upto 2 decimal places) Here I am getting 5.98Mbps,can anyone confirm this.
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A simple network consist of two nodes X and Y. Each node has a single frame of F = 1500 bits (including all header and preambles) to send to each other. Both nodes attempt to transmit at t = 0'. In case that a node executes the exponential Back-off algorithm. In the algorithm, a node ... 8 μs, then TT + PT. And TT = 10 μs and PT = 4 μs, and thus it is total 36μs. but the answer given is 26μs.
1 vote
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Hi Guys, In Ethernet whenever collision happens station sends a Jamming signal. But why does these special signal not collide ? In many question i saw they also have TT and TP. So what does make them collision free ? PS: Refer Problem 2 on http://web.eecs.umich.edu/~zmao/eecs489/MT2/mt2reviewHints.pdf
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1. To transmit and receive digital data between islands using the CSMA / CD multiple access protocol do. As shown in the picture below, the distance between any two islands is 10km . Each island has a digital transceiver compliant with the CSMA / CD protocol. It ... At this time, the retransmitted islands How long do you want to wait and start sending again? Of course, CSMA / CD protocol.
Consider a network consists of 4 interconnected nodes, P,Q,R,S. Distance between them are follows:PQ=254km, PR=243km,PS=287km, QR=239km , QS=300km, RS=120km. The network uses CSMA/CD and signal travels at a speed $2\times 10^{5}$km/sec. If sender sends at a rate 1Mbps, then what could be min size of the pcket?(in bits)