問56
頻出度★★★
ネットワークのデータ伝送速度を表す単位はどれか。
平成23年度 秋期 ITパスポート試験 問56
テクノロジ系ネットワーク › ネットワーク方式
This question's explanation and your answers so far.
解説
問 56
- ア
正解 bps stands for bits per second, a unit expressing how many bits of data can be sent in one second. The transmission speed (communication speed) of a network is measured as the amount of data that can be carried per unit of time, so bps is the standard unit for it. The larger the value, the faster it is; in practice, each step of 1,000 times is rewritten as kbps (kilobits per second), Mbps (megabits per second), and Gbps (gigabits per second). For example, a 100 Mbps line can in theory send about 100 million bits (about 12.5 megabytes) in one second. Note also that when the amount of data is expressed in bytes, you convert using 1 byte = 8 bits.
Incorrectイ
fps stands for frames per second, a unit expressing how many frames a video or animation displays in one second. It indicates how smooth the moving image looks and has nothing to do with the amount of data a network can carry per second, so it is wrong.
Incorrectウ
ppm stands for pages per minute, a unit of printing speed expressing how many pages a printer can print in one minute. It is a performance measure for a peripheral device, not a unit for the transmission speed of a communication line, so it is wrong.
Incorrectエ
rpm stands for revolutions per minute, a unit expressing how many times the magnetic disks of a hard disk and similar parts rotate in one minute. It indicates the rotation speed of a device, a different concept from the data transmission speed of a network, so it is wrong.
ここがポイント
- The unit of transmission speed is bps (bits per second) = the number of bits that can be sent in one second. Large values are written in steps of 1,000 as kbps / Mbps / Gbps, and byte conversion uses 1 byte = 8 bits.
- Distinguish the easily confused per-second / per-minute units by the field they belong to: fps = the frame count of a video (frames per second), ppm = the printing speed of a printer (pages per minute), rpm = the rotation of disks and the like (revolutions per minute).
用語