平成28年度春期 ITパスポート試験問99

This question's explanation and your answers so far.

問99

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インタフェースの規格①～④のうち，接続ケーブルなどによる物理的な接続を必要としない規格だけを全て挙げたものはどれか。 ① Bluetooth ② IEEE 1394 ③ IrDA ④ USB 3.0

出典　平成28年度春期 ITパスポート試験問99

解説

問 99

Incorrectア
This is the combination “①, ②”. ① Bluetooth is wireless, but ② IEEE 1394 (FireWire) is a wired standard that connects devices with a dedicated cable and requires a physical connection. It violates the “wireless only” condition, so it is incorrect.
イ
正解 The question asks for the standards that “do not require a physical connection via a connecting cable or the like” — in other words, interface standards that exchange data wirelessly. ① Bluetooth is a wireless communication standard using radio waves in the 2.4 GHz band, so no cable connection is needed. ③ IrDA is a wireless communication standard using infrared light, which likewise needs no cable. Therefore the combination “①, ③”, which gathers only the wireless standards, is correct, and the answer is “イ”.
Incorrectウ
This is the combination “②, ③”. ③ IrDA is wireless via infrared, but ② IEEE 1394 requires a wired cable connection. Because it includes a wired standard, it is incorrect.
Incorrectエ
This is the combination “③, ④”. ③ IrDA is wireless, but ④ USB 3.0 is a wired serial interface standard that connects via a cable. Because it requires a physical connection, it is incorrect.

ここがポイント

Be able to classify interface standards by whether they are wired or wireless. Typical wireless examples (no physical connection needed) are Bluetooth (radio waves) and IrDA (infrared), while typical wired examples (cable connection) are IEEE 1394 and USB 3.0.
Keep in mind the transmission medium of each standard: IrDA is short-range data communication using infrared light, and Bluetooth is short-range wireless communication using radio waves.

用語

解答問99イ