問100
頻出度★★★
無線LANにおいて，あらかじめアクセスポイントへ登録された機器だけに接続を許可するセキュリティ対策はどれか。
平成29年度 春期 ITパスポート試験 問100
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 100
Incorrectア
“Rejecting ANY connection” is a setting that rejects connections from devices that try to connect by specifying “ANY” for the ESSID or leaving it blank (i.e., requesting to connect to any access point). It does not permit only specific registered devices; it merely blocks indiscriminate connection requests that do not specify an ESSID, so it is incorrect.
Incorrectイ
“ESSID stealth (hiding)” is a measure that stops the access point from broadcasting (beaconing) its ESSID (network name), making its presence harder to notice. It only makes the network harder for third parties who do not know the network name to discover; it is not a mechanism that registers devices in advance to decide whether to permit or reject them, so it is incorrect.
- ウ
正解 The correct answer is ウ, “MAC address filtering.” The NIC of a network device is assigned a unique MAC address at the time of manufacture. You register in advance the MAC addresses of the devices allowed to connect to the access point, and when a device requests communication, the access point checks whether that MAC address is already registered; only registered devices are permitted to connect, and unregistered devices are rejected. This exactly matches the condition in the question of permitting only devices registered in advance.
Incorrectエ
“WPA2” is a standard for wireless LAN encryption (and authentication) that prevents eavesdropping on communication content and handles authentication using methods such as a pre-shared key. Because any device that knows the correct password (key) can connect, it differs from a mechanism that registers individual devices in advance to limit which ones are permitted; it does not match the condition in the question, so it is incorrect.
ここがポイント
- MAC address filtering = a measure that registers the MAC addresses of permitted devices in advance at the access point and allows only registered devices to connect.
- Be able to distinguish the different roles of each wireless LAN measure (rejecting ANY connection = rejecting indiscriminate connections, ESSID stealth = hiding the network name, WPA2 = encryption and authentication).
用語