GCSE (9-1) Computer Science
Mark Scheme
J277/01: Unit 1.3 Wired vs Wireless Networks
Question Answer Marks Guidance
1a
  • Row 1: Bluetooth
  • Row 2: Ethernet
  • Row 3: Wi-Fi
 3
AO1 (Knowledge)
1 mark per correct tick.
If multiple ticks appear in one row, award 0 for that row.
1b Ethernet Cable / Copper Cable / Twisted Pair Cable (1) 1
Allow: Cat5/Cat6 cable.
Reject: "Wire" (too vague) or "Switch" (Wireless networks also utilize switches in the background, though less visibly).
2a Speed/Bandwidth: Ethernet offers higher bandwidth / faster transmission speeds (1)... which allows large video files to upload quicker (1).

Stability/Interference: Wired connections are not affected by interference (from walls/other devices) (1)... so the upload is less likely to fail or lag (1).

Security: Wired connections are harder to intercept (1)... which keeps her professional work secure (1). 		4
AO2 (Application)
Examiner's Note: "Faster" on its own is NE (Not Enough). Must specify "transmission speed" or link to "upload time".
Answers must relate to Sam or Video Editing (e.g., "large files", "professional work").
2b
  • Point: Wi-Fi allows mobility / device is portable (1).
  • Explanation: ...so she can move around the garden without being tethered by a cable (1).
 2
Key Concept: Portability / Convenience.
Reject: "It is easier" (Too vague).
3a Any 3 points (1 mark each):
  • Number of users on the network (sharing bandwidth).
  • Distance from the WAP / Signal strength.
  • Physical obstructions (Walls, ceilings, furniture).
  • Interference from other electronic devices / overlapping channels.
 3
Reject: "Weather" (Unless extreme, usually not a primary factor for indoor Wi-Fi in spec).
Reject: "Viruses" (This affects the computer, not the network signal transmission).
3b
  • Wireless signals broadcast data in all directions, so they can be easily intercepted by hackers (1).
  • Encryption scrambles the data so it cannot be understood (is meaningless) without the key (1).
 2
Common Pitfall: Students often say encryption "stops data being stolen". It doesn't stop theft; it makes the stolen data unreadable. Award marks for "unreadable" / "meaningless".
4a
  • Range: Wi-Fi has a larger/longer range than Bluetooth (or vice versa) (1).
  • Bandwidth: Wi-Fi has a higher bandwidth / faster data transfer rate than Bluetooth (1).
 2
Must be a comparison. "Bluetooth is slow" = 0 (Need "slower than Wi-Fi").
Accept: Specific ranges if accurate (e.g., "Bluetooth is approx 10m, Wi-Fi is approx 50-100m").
4b
  • The speaker may be in a different room (needs range).
  • Streaming high-quality audio requires higher bandwidth than Bluetooth offers.
  • Don't need to keep the phone/controlling device near the speaker.
 1
Accept: Any valid reason linking the device nature (Smart Speaker) to Wi-Fi strengths (Range/Bandwidth).
5
Indicative Content:
Option A: Ethernet (Wired)
Pros: Faster transmission speeds; dedicated bandwidth (not shared per WAP); more stable (no interference); more secure (need physical access).
Cons: Expensive installation; time-consuming; No mobility; trip hazards.
Option B: Wi-Fi (Wireless)
Pros: Mobility; easier/cheaper to install; allows BYOD.
Cons: Shared bandwidth (lag); signal blocked by walls; less secure.
Conclusion: Hybrid approach often best.

Levels:
Level 3 (6–8): Detailed discussion of both options using technical terms. Addresses multiple factors and relates to school context.
Level 2 (3–5): Comparison present but unbalanced. Some technical terms. Context mentioned.
Level 1 (1–2): Basic points made. Little explanation or technical terminology. 		8
AO1/AO2/AO3 (Extended Response)
Marked using Levels of Response.
OCR 2026