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Wired, wireless and network speed
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Cables and Wi-Fi each have strengths. Network speed questions are about bits, seconds and careful units.
Key terms
Bandwidth: the maximum amount of data that can be sent per second.
Latency: the delay before data starts to arrive.
Range: how far the signal reaches.
Speed (transmission rate): bits per second actually achieved.
Latency: the delay before data starts to arrive.
Range: how far the signal reaches.
Speed (transmission rate): bits per second actually achieved.
Wired or wireless?
Speed calculations
Network speeds use bits per second: 1 kilobit = 1000 bits, 1 megabit (Mbps) = 1 000 000 bits, 1 gigabit = 1 000 000 000 bits.
time = file size ÷ transmission rate
Make the units match: convert bytes to bits by multiplying by 8.
time = file size ÷ transmission rate
Make the units match: convert bytes to bits by multiplying by 8.
How long does it take to send a 25 megabyte file over a 50 Mbps connection? (1 megabyte = 1 000 000 bytes)
- 25 megabytes × 8 = 200 megabits
- 200 ÷ 50 = 4 seconds
Answer: 4 seconds
Wired is faster, more reliable and more secure; wireless gives mobility but has more latency and interference. Time = size ÷ rate, with sizes in bits.
The interactive lesson includes the diagrams for this topic.
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