This key facts covers How Packet Switching Works 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 5 of 11 in this topic. Use this key facts to connect the idea to the wider topic before moving on to questions and flashcards.
Topic position
Section 5 of 11
Practice
15 questions
Recall
18 flashcards
How Packet Switching Works
Step-by-Step Process:
1. Data Division:
- Large message/file broken into small packets (e.g., 1MB file → 700 packets of 1500 bytes)
- Each packet numbered for reassembly
2. Adding Headers:
- Each packet gets header with source/destination IP, packet number
- Trailer added with error-checking information
3. Transmission:
- Packets sent across network independently
- Each packet can take different route through routers
- Routers forward packets based on current network conditions
4. Routing:
- Routers read destination IP in header
- Choose best available route (fastest, least congested)
- Different packets may take different paths
5. Arrival:
- Packets arrive at destination (possibly out of order)
- Error checking performed using trailer
- Damaged packets reported, retransmission requested
6. Reassembly:
- Packets sorted using sequence numbers
- Reassembled into original message/file
- Complete data delivered to application