GATE CS 2015 Set 3 — Question 35
Go beyond PYQs with Success TrackerAI-powered personalised practice and doubt support. Unlimited practice on eligible plans; AI usage limits apply.MCQ+1 / -0.33MediumCSMA/CDMedium Access & LANsComputer NetworksEfficiency NumericalsData Link Layer
Computer Networks → Data Link Layer → CSMA/CD
Last updated
Question
Consider a CSMA/CD network that transmits data at a rate of 100 Mbps ( bits per second) over a 1 km (kilometer) cable with no repeaters. If the minimum frame size required for this network is 1250 bytes, what is the signal speed (km/sec) in the cable?
Correct answer
(D) 20000
Solution
For CSMA/CD, the condition for collision detection is:
Transmission Time () Propagation Time ()Given:
Bandwidth () = 100 Mbps = bps
Distance () = 1 km
Frame Size () = 1250 bytes = bits = 10,000 bits secondsLet signal speed be km/sec.
secondsSubstitute into the condition:
km/secThe minimum signal speed required is 20,000 km/sec.
Transmission Time () Propagation Time ()Given:
Bandwidth () = 100 Mbps = bps
Distance () = 1 km
Frame Size () = 1250 bytes = bits = 10,000 bits secondsLet signal speed be km/sec.
secondsSubstitute into the condition:
km/secThe minimum signal speed required is 20,000 km/sec.
Continue learning with Success Tracker
A step still unclear? Work through it with support
Use Success Tracker to ask about the reasoning, then try another GATE CS question to check your understanding.
AI-powered practice· Unlimited practice on eligible plans
- PYQs with solutions
- Attempt available previous-year questions, then compare your reasoning with the worked solution. Coverage varies by stream.
- Practice that adapts
- Choose a topic, work on weaker areas and bookmark questions to revisit. Your attempts feed your progress tracking.
- AI doubt support
- Ask follow-up questions about a step or concept while practising, instead of stopping at the final answer.
Unlimited practice is available on eligible plans. Free practice and AI usage have limits; check the current plan allowances before choosing.
This page stays readable without an account. AI responses can be wrong; check them against the solution and source material.
More questions on Data Link Layer
2026 Set 1 Q18With respect to a TCP connection between a client and a server, which one of the following…2026 Set 1 Q19Which of the following statements is/are true with respect to the interaction of a web browser with…2026 Set 2 Q21Consider a file of size 4 million bytes being transferred between two hosts connected via a path…2026 Set 2 Q22Which one of the following protocols may need to broadcast some of its messages?2026 Set 2 Q33If an IP network uses a subnet mask of 255.255.240.0, the maximum number of IP addresses that can…