問63
頻出度★★★
IPv6に関する記述として, 適切なものはどれか。
平成25年度 秋期 ITパスポート試験 問63
テクノロジ系ネットワーク › ネットワーク応用
This question's explanation and your answers so far.
解説
問 63
- ア
正解 IPv6 has an address length of 128 bits, so compared with IPv4, which had 32 bits, its address space is orders of magnitude larger and IP addresses can be assigned to many more devices. The biggest motivation for creating IPv6 was precisely to deal with the exhaustion of IPv4 addresses, and choice “ア” correctly states this central feature.
Incorrectイ
It is possible to run IPv6 and IPv4 at the same time on one LAN. A typical example is dual stack, the representative method used during the transition period (a device has both the IPv4 and the IPv6 protocol stacks), so the statement that they cannot coexist is wrong.
Incorrectウ
IPv6 is a network-layer (internet-layer) protocol, and it does not matter whether the data link layer beneath it is a wired LAN or a wireless LAN. IPv6 can be used on wireless LANs and on mobile phone networks as well, so the statement that it is exclusively for wired LANs is wrong.
Incorrectエ
The transmission medium (twisted-pair cable or fiber-optic cable) is a matter of the physical layer, which is a different layer from IPv6. IPv6 can be used as it is on a LAN with ordinary twisted-pair cable, so the statement that fiber-optic cable is required is wrong.
ここがポイント
- The address length of IPv6 is 128 bits, and that of IPv4 is 32 bits. The main purpose of IPv6 is to cope with the exhaustion of IPv4 addresses, and the expanded address space is its biggest feature.
- IPv6 is a network-layer protocol, so it does not depend on the transmission medium (twisted pair or fiber-optic) or on whether the connection is wired or wireless. During the transition period it can coexist with IPv4 using dual stack.
用語