Communications technology (A Level only)：練習問題

• a.DHCP
• b.DNS
• c.SMTP
• d.ICMP

• a.

  Connection mode relies on a broadcast signal to all nodes, while connectionless mode uses a specific MAC address to target a single recipient.

• b.

  In connection mode, a virtual circuit is established before data is sent, whereas in connectionless mode, each packet is treated independently and can follow different routes.

• c.

  Connection mode only uses hardware routers, while connectionless mode relies entirely on software-based gateways to direct traffic.

• d.

  In connectionless mode, all packets are guaranteed to arrive in the correct sequence, whereas connection mode requires the receiver to reorder them.

• a.

  Risk analysis is performed only after a disaster occurs to determine the cause, while risk testing is the process of backing up data to an offsite server.

• b.

  Risk analysis focuses on physical security threats like theft, whereas risk testing focuses solely on software-based threats like malware and SQL injection.

• c.

  Risk analysis involves identifying and quantifying potential threats and their impact, while risk testing involves simulating a disaster to evaluate the effectiveness of the recovery plan.

• d.

  Risk analysis is a software-automated process for detecting intruders, whereas risk testing is a manual audit of user password complexity policies.

• a.

  In connection mode, a logical path is pre-defined before data is sent, whereas in connectionless mode, each packet is treated as an independent unit with no pre-established path.

• b.

  Connection mode requires the use of physical circuit switching, while connectionless mode relies exclusively on message switching and store-and-forward methods.

• c.

  In connection mode, data is sent as a single continuous stream without headers, whereas connectionless mode requires data to be broken into packets with MAC addresses.

• d.

  Connection mode is used only for local area networks (LAN), while connectionless mode is used strictly for wide area networks (WAN) and satellite communications.

• a.Packet switching stores data on a magnetic tape file for archival, whereas message switching only uses solid-state drives for temporary storage.
• b.Message switching requires a dedicated physical path to be established between the sender and receiver before transmission starts, whereas packet switching does not.
• c.Message switching is a connection-oriented mode using the Transmission Control Protocol (TCP), while packet switching is always connectionless.
• d.In message switching, the entire data unit is stored at each intermediate node before being forwarded, while packet switching divides data into smaller units that can follow different routes.

まず自分で答えを書いてから、解説と照らし合わせましょう。

まず自分で答えを書いてから、解説と照らし合わせましょう。

まず自分で答えを書いてから、解説と照らし合わせましょう。

まず自分で答えを書いてから、解説と照らし合わせましょう。

まず自分で答えを書いてから、解説と照らし合わせましょう。