# Recent questions tagged stop-and-wait 1
Consider a network topology using STOP and WAIT protocol A---------R----------B (here R is STORE and FORWARD ROUTER) Tp=1uS , Tx(data)=1000uS, Tx(ack)=10uS File Size =10000bits, Packet size=1000bits. How long will it take for A to send whole file to B? Dobut ... to A then A will Transmit second packet OR here A will send packet toHost B and B will send ack back to A then A will send second packet
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Frames of 1000 bits are sent over a 1-Mbps channel using a geostationary satellite whose propagation time from the earth is 270 msec. Acknowledgements are always piggybacked onto data frames. The headers are very short. Three-bit sequence numbers are used. What is the maximum achievable channel utilization for (a) Stop-and-wait? (b) go back n? (c) selective repeat?
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(a) The distance from earth to a distant planet is approximately 9 1010 m. What is the channel utilization if a stop-and-wait protocol is used for frame transmission on a 64 Mbps point-to-point link? Assume that the frame size is 32 KB and the speed ... . For what send window size will the link utilization be 100%? You may ignore the protocol processing times at the sender and the receiver.
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A channel has a bit rate of 4 kbps and a propagation delay of 20 msec. For what range of frame sizes does stop-and-wait give an efficiency of at least 50%?
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$Que-$ A sender uses a Stop-and-Wait protocol for transmission of $8000 \ K-bits$ size frames on a $1Gbps$ satellite channel with a propagation delay of $400 \ ms$. What will be the link utilization (%) if a probability of single frame error is $0.001?$ $\text{Note – Here Frame size is 8000 K- bits i.e 8}*10^6 \ bits$
1 vote
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Consider a half-duplex link with a one-way propagation delay of $P$ seconds and a bandwidth of $B$ bits/sec. The sender and the receiver decide to share the link using Time Division Multiplexing i.e. the sender sends for $T_s$ time and then receiver sends for $T_r$ time and so on. Refer to the figure below. Assume that the ... $(2/B)*(F+A)+P$ $(1/B)*(F+A)+2*P$ $(2/B)*(F+A)+2*P$
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A colony is set up on moon. The 10 Mbps link from the earth to the lunar colony measures about 242,000 miles. Assume that the signal propagation speed is 186,000 miles per second. Calculate the minimum round trip time for the link. Using RTT as the ... sender and receiver ends. SRP with window size 8 and negligible processing delay. Go Back-n with window size 64 and negligible processing delay.
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Sender Window Size is 7 and every 3rd packet is lost/corrupted. So, how to find channel utilization!?
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Consider the use of 10 K-bit size frames on a 10 Mbps satellite channel with 270 ms delay. What is the link utilization for stop-and-wait ARQ technique assuming P = 10-3? My doubt - In frame size 10 K-bit, what should you take value of K? i.e K as 1000 bits or K = 1024 bits? I'm more ... ) = (10 K-bit) / (10 Mbps) = 1 msec Hence, a = 270/1 = 270 Link utilization = 0.999/(1+2*270) ≈0.0018 =0.18%
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Original question link - https://gateoverflow.in/78987/packet-loss-numerical-in-stop-and-wait I know this question has already been solved by Arjun Sir, but is there any other explanation which can simplify things? In a communication link out of p packets one packet will be lost. If stop and wait ... used then expected number of retransmissions for a packet? (A) P/(1-P) (B) P (C) 1/(1-P) (D) 1/P
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A sender uses the Stop-and-Wait ARQ protocol for reliable transmission of frames. Frames are of size 1000 bytes and the transmission rate at the sender is 80 Kbps (1 Kbps = 1000 bits/second). Size of an acknowledgement is 100 bytes and the transmission rate ... 8 Kbps. The one-way propagation delay is 100 milliseconds. Assuming no frame is lost, the RECIEVER throughout is ________ bytes/ second.
1 vote
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A geosynchronous satellite has a half-duplex channel with a transmission rate of 10 kbps and a propagation delay of 0.25 sec each way. With a data packet size of 1000 bits and a loss probability p of 0.001 ,(A) what is the expected transmission time of a packet ... all other parameters are the same as part (a), what is the longest channel propagation delay for which we can still use stop-and-wait?
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The distance from earth to a distant planet is approximately 9*(10^10) m. What is the channel utilization if a stop-and-wait protocol is used for frame transmission on a 64Mbps point-to-point link? Assume that the frame size is 32KB and the speed of light is 3*(10^8) m/s.
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nice ques from CN,can anyone solve this?
1 vote
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Consider Host-A want to transmit data of size 105000 B to Host-B. The communication between Host-A and Host-B is birectional with bandwidth of link between them is 100 Mbps in both direction. Data will be transferred in packet of size 1500 Byte and header size is ... e. process time. The throughput for this transfer if stop wait protocol with pipelining is used ________. (in KBps) Ans: 144.06 KBps
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Consider that the stop and wait protocol is used on a link with bit rate of 128 Kbps and 40 msec as round trip time. Assume that the transmission time for the acknowledgment and processing time at nodes are negligible. If the frame size is 512 B then the link utilization is ________. (In % upto 2 decimal places)
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In a communication link out of p packets, one packet will be lost. If stop and wait protocol is used then expected number of retransmissions for a packet? (A) P/(P-1) (B) P (C) 1/(P-1) (D) 1/P
1 vote
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why stop and wait protocol has flow control but not error control ?
1 vote
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Consider a wireless link, where the probability of packet error is 0.6. To transfer data across the links, Stop and Wait protocol is used. The channel condition is assumed to be independent from transmission to transmission. The average number of transmission attempts required to transfer x packets is 500. The value of x is _______.
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Assume a network that does not drop, duplicate, or corrupt any packets and that you are using a stop-and-wait protocol between two endpoints, A and B. The time it takes for a packet to get from A to B is uniformly distributed between 10 and 20ms. The time it takes ... 50% of the time you will not have to retransmit it due to a timeout. What is the largest possible timeout you can choose (in ms)?
1 vote
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Hi Guys, Do you know formula for efficiency of Stop-and-Wait, Selective Reject and Go-Back-N ARQ when error probability is p ? PS: Although i am mentioning the link for answer but if you want to add some additional info.(or some more elegant proof for the formula) then it will be really helpful for all readers. :)
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In a Stop and WaIT ARQ protcol given Bandwidth = 1Mbps and 1bit RTT = 20ms ,Frame size is 1000bits whats the % Utilization of the link? Soln. My approach is :- Bandwidth delay pdt = 1x10^6 x 20 x10^-3 = 20000bits And system sends 1000bits at a time so 1000/20000 = 5% Is this approach Correct? Other way :- U = Tr/(Tr + RTT) but by this answer doesnt matches Plz Correct me
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In calculating efficiency of stop and wait protocol, if its given that the information frame is, say 80 bytes and overhead data(header?) is 20 bytes, then we'll calculate transmission time of 100 bytes or 80 bytes, as part of the process? I am asking coz this *is* bringing a difference in numerical value of my answer.
The values of parameters for the Stop-and-Wait ARQ protocol are as given below: Bit rate of the transmission channel = $1$ Mbps. Propagation delay from sender to receiver = $0.75$ ms. Time to process a frame = $0.25$ ms. Number of bytes in ... efficiency (expressed in percentage) of the Stop-and-Wait ARQ protocol for the above parameters is _____________ (correct to $2$ decimal places).
The problem: Given: $B=$ 64 kbps satellite channel $L=$ 512 B data frames Round Trip Time (RTT) = 64 ms What is the maximum throughput for window size of 1?