Published Book on Amazon
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All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 1 |
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All of IOT Starting with the Latest Raspberry Pi from Beginner to Advanced – Volume 2 |
출판된 한글판 도서
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최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (상) |
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최신 라즈베리파이(Raspberry Pi)로 시작하는 사물인터넷(IOT)의 모든 것 – 초보에서 고급까지 (하) |
Original Book Contents
14.1.4 Network Device
14.1.4.1 Characteristics of Network Device
In Linux, a network device is thought of as an entity that sends and receives data packets. A network device is usually a physical device, such as an Ethernet card. However, there are some network devices defined with only software, such as loopback device that is used to send data to itself.
On Linux, when the kernel boots, the network devices that it controls are registered with Linux during initialization of the network device driver. As the network device is registered when Linux initializes the network on the system, so no device is registered for devices that do not actually exist.
Files created for network devices are not registered in "/dev" directory. To check the contents, you need to use "ifconfig" command.
14.1.4.2 Device Type and Naming Rules of Network
■ Writed Ethernet device
■ It means a device connected to a network through a wired LAN cable.
■ Naming rule -- eth + n -- 0, 1, 2 …
■ Wi-Fi Ethernet device
■ It means a device that connects to the network through Wi-Fi.
■ Naming rule -- wlan + n -- 0, 1, 2 …
■ Loopback device
■ A loop back device is a device embedded in a system, not a separate physical device on the network, but a virtual interface device that refers to itself in the network.
■ Naming rule -- lo
■ SLIP device
■ SLIP (Serial Line Internet Protocol) is one of communication methods that use a telephone modem and is a protocol enabling to connect and use a network using a telephone line.
■ Naming rule -- sl + n -- 0, 1, 2 ..
■ PPP device
■ PPP (Point to Point Protocol) is one of communication methods that uses a telephone modem, and is a protocol enabling to connect and use a network using a telephone line. Compared to SLIP method, although it can handle many packets of protocol at the same time, it is complicated and difficult to implement, so SLIP is usually used.
■ Naming rule -- ppp + n