問79
頻出度★★☆
DHCPサーバを導入したLANに, DHCPから自動的に情報を取得するように設定したPC を接続するとき, PCに設定される情報として適切なものはどれか。
平成26年度 秋期 ITパスポート試験 問79
テクノロジ系ネットワーク › 通信プロトコル
This question's explanation and your answers so far.
解説
問 79
- ア
正解 The correct answer is ア, the IP address. DHCP (Dynamic Host Configuration Protocol) is a protocol that automatically assigns the network configuration information needed for communication to client PCs that connect to a network. If the PC is set to obtain an IP address automatically, then when it connects it asks the DHCP server for configuration information, and the server picks an unused IP address from the address pool it manages and leases it to the PC. The typical information DHCP distributes includes the IP address, the subnet mask, the address of the default gateway (router), and the address of the DNS server, all of which are network-layer settings required to communicate on that LAN. Among the choices, only the IP address fits this description, so ア is appropriate. As a result, the administrator no longer has to set an IP address by hand on each individual PC, and duplicate addresses and configuration mistakes are also prevented.
Incorrectイ
Incorrect. Distributing and updating virus definition files (pattern files) is the job of antivirus software and its management server (distribution server), not a function of DHCP. DHCP handles only configuration information for network connectivity; it does not distribute the data files of security software.
Incorrectウ
Incorrect. Holding and applying a list of spam sender addresses (a blacklist) is the role of a mail server or a spam filter (anti-spam software), and has nothing to do with DHCP. DHCP is not involved at all in judging the content or the sender of email.
Incorrectエ
Incorrect. The email address assigned by the provider (ISP) is account information that is given to the user when the contract is made and that must be entered manually into the mail client; it is not something the DHCP server on the LAN distributes automatically. What DHCP distributes is strictly network settings such as the IP address, subnet mask, default gateway, and DNS server address.
ここがポイント
- DHCP is a protocol that automatically assigns network configuration information such as the IP address, subnet mask, default gateway, and DNS server address to clients that connect to a network. Its purpose is to eliminate the effort of manual configuration and to prevent duplicate addresses.
- What DHCP distributes is limited to network-layer connection settings. Application-layer data and account information such as virus definition files, anti-spam blacklists, and email addresses are each handled by a different mechanism (an antivirus management server, a spam filter, and the contract with the ISP, respectively).
用語