Summary of knowledge about the network (1)

In classes to improve the process of communicating with Shige senior sister apprentice, we found a lot of heard of, but do not know the contents of what it means, so Baidu Encyclopedia about, learn about, from the basics (part excerpt from Baidu Encyclopedia explanation)
1. Port : "Port" is a free translation of English port, which can be considered as an outlet for communication between the device and the outside world. Ports can be divided into virtual ports and physical ports. The virtual port refers to the port inside the computer or the switch router and is not visible. For example, port 80, port 21, port 23, etc. in a computer. The physical port is also called the interface, which is the visible port, the RJ45 network port on the computer backplane, the RJ45 port such as the switch router hub. The use of RJ11 jacks for phones also belongs to the category of physical ports. Add link description
2. Switch: Switch means "switch" is a network device used for electrical (optical) signal forwarding. It can provide an exclusive electrical signal path for any two network nodes connected to the switch. The most common switch is an Ethernet switch. Other common ones are telephone voice switches, optical fiber switches, etc. Add link description
3. Communication protocol: One of the earliest protocols in the open system interconnection protocol. It provides communication support for interconnection networks connecting different operating systems and different hardware architectures. It is a common network language. The TCP/IP protocol defines how to transfer and manage information (file transfer, sending and receiving e-mail, remote login, etc.) in the Internet, and formulates the rules that must be followed when errors occur. Add link description
4. Router: (Nowadays every family has something, but we have thought about what a router means and how it works?)
A router is a hardware device that connects two or more networks. It acts as a gateway between networks. It is a dedicated intelligent network device that reads the address in each data packet and then decides how to transmit it. It can understand different protocols, such as the Ethernet protocol used by a local area network and the TCP/IP protocol used by the Internet. In this way, the router can analyze the destination addresses of data packets from different types of networks, and convert the addresses of non-TCP/IP networks into TCP/IP addresses, or vice versa; and then according to the selected routing algorithm, each data packet can be optimized The best route is transmitted to the designated location. So the router can connect non-TCP/IP networks to the Internet. Add link description
5. What is the difference between AP and router Add link description