Give two benefits and two drawbacks of packet switching. Benefit 1 Benefit 2 Drawback 1 Drawback 2

Mark scheme

Marking points from the official mark scheme (May/June 2021). The mark or mark type is shown in brackets.

1. [4] Benefit: Accuracy - Ensures accurate delivery of the message
2. Benefit: Completeness – Missing packets can be easily detected and a re-send request sent so the message arrives complete
3. Benefit: Resilience - if a network changes the router can detect this and send the data another way to ensure it arrives
4. Benefit: Path also available to other users // Doesn't use whole bandwidth // allows simultaneous use of channel by multiple users
5. Benefit: Better security as packets hashed and sent by different routes.
6. Drawback: Time delays to correct errors // Network problems may introduce errors in packets
7. Drawback: Requires complex protocols for delivery
8. Drawback: Unsuitable for real time transmission applications