This exam tips covers Exam Tips - Packet Switching within Packet Switching for GCSE Computer Science. Revise Packet Switching in Networks for GCSE Computer Science with 15 exam-style questions and 18 flashcards. This topic appears regularly enough that it should still be part of a steady revision cycle. It is section 10 of 11 in this topic. Treat this as a marking guide for what examiners are looking for, not just a fact list.
Topic position
Section 10 of 11
Practice
15 questions
Recall
18 flashcards
Exam Tips - Packet Switching
Most common exam questions:
- "What is packet switching?" → Data broken into packets, each packet travels independently, reassembled at destination
- "What's in a packet?" → Header (source/dest IP, packet number), Payload (data), Trailer (error checking)
- "Advantage of packet switching?" → Efficient network use / resilient (packets reroute around failures)
- "Disadvantage of packet switching?" → Packets arrive out of order (need reassembly) / variable latency
- "Why split into packets?" → Efficient sharing of network / can reroute if failure / only retransmit lost packets
Key facts to memorize:
- Packets = small chunks (500-1500 bytes typically)
- Header contains: source/destination IP, packet number
- Trailer contains: error checking (checksum/CRC)
- Each packet can take different route
- Packets reassembled using sequence numbers
Common mistakes to avoid:
- Forgetting packets can take different routes - key feature!
- Not mentioning reassembly at destination
- Confusing packet switching with circuit switching
- Missing the three parts: header, payload, trailer
Perfect exam answer:
"Explain how packet switching works" (4 marks):
Data broken into small packets (1 mark).
Each packet has header with source/destination IP and packet number (1 mark).
Packets travel independently through network, can take different routes (1 mark).
Packets reassembled in correct order at destination using sequence numbers (1 mark).