問60
頻出度★★★
ネットワーク機器がパケットを複製して, 複数の宛先に送ることを何というか。
平成27年度 秋期 ITパスポート試験 問60
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 60
Incorrectア
DNS is a name resolution mechanism that converts between domain names and IP addresses; it is not a communication method that duplicates packets and distributes them to multiple destinations.
Incorrectイ
A URL is a notation (an address string) that indicates the location of a resource on the Web; it is not a term describing a communication delivery method, so it is incorrect.
- ウ
正解 The correct answer is choice ウ, Multicast. Multicast is a communication method that sends the same data to multiple destinations belonging to a specific group; the sender only needs to send a single packet, and network devices (such as routers) duplicate the packet as needed along the path and deliver it to each destination. This exactly matches the action described in the question, “duplicating a packet and sending it to multiple destinations,” so ウ is correct.
Incorrectエ
Multilink is a technology that bundles multiple physical lines and treats them as a single logical line to increase communication speed; it has nothing to do with duplicating and sending packets to multiple destinations.
ここがポイント
- Multicast = a method of sending the same data to a specific group of multiple destinations. The sender sends only one copy, and devices along the path duplicate the packet and distribute it.
- Distinguish the delivery scope: one-to-one = unicast, one-to-all = broadcast, one-to-specific-group = multicast.
用語