Common network protocols:
1. TCP/IP protocol
(1) Basic concepts
TCP/IP protocol (Transmission Control Protocol/Internet Protocol) transmission control/Internet protocol, also called network communication protocol.
It is a network architecture and protocol standard developed by the US Department of Defense for its ARPANET wide area network in the mid-1970s. The Internet based on it is currently the largest computer network in the world.
This protocol is the foundation of the Internet and the basic communication protocol used in the network.
Note : While watching TCP / IP protocol includes two, Transmission Control Protocol (TCP) and Internet Protocol (IP) from the name, but TCP / IP is actually a suite of protocols , including the protocol hundreds of various functions,
The more important one is SLIP Protocol, PPP protocol, IP protocol, ICMP protocol, ARP protocol, TCP protocol, UDP protocol, FTP protocol , DNS protocol, SMTP protocolWait.
The TCP protocol and the IP protocol are two basic and important protocols to ensure complete data transmission . Generally speaking, TCP/IP is an Internet protocol family, not just TCP and IP. Because of the widespread use of INTERNET, TCP/IP has become the de facto standard.
(2) Important protocols
1. Transport layer protocol:
TCP reliable transmission protocol, which will ensure that the content received by the receiver is correct, without loss, and the sequence is consistent with the sender (if the error and disorder cannot be recovered, the upper layer protocol will be notified) udp is an unreliable transmission protocol, which does not guarantee that the content received by the receiver is correct, missing, or out of order; in this way, only the upper layer processing can ensure the reliability of transmission
2. Application layer protocol:
These are the upper-layer protocols in the internet protocol stack and have nothing to do with the operating system
Hypertext protocol
: http is a text (or content) description language, a specification for describing and interpreting content. The webpage we are using is made in accordance with this kind of specification.
Note: The browser (netscape ie) use the specification to explain it to us to show the
File Transfer Protocol :
the FTP and tftp is used for file transfer The main difference is that it is different from the transport layer protocol used
Most systems in the world will have tools that support FTP, which is very versatile. Few people have modified VPS to support FTP components, mainly because FTP was not designed for file systems from the beginning.
The login password of the standard FTP protocol is transmitted in plain text without encryption, which has great security risks. Currently, there are FTP protocols that are encrypted based on the communication layer such as FTPs (FTP on SSL/TLS) and sFTP (SSH FTP). , This will have better security.
Mail Transfer Protocol:
SMTP mail transmission specifications, to the email transmission
characters transport protocols:
Telnet specification character is transmitted, the main application used in the transport layer protocol bbs control apparatus, which specification is TCP (reliable delivery)
Domain Resolution:
dns is a domain name resolution service, such as resolving www.baidu.com into the corresponding ip address (network communication uses ip addresses, but people are used to remembering domain names) above:
tcp protocol: ftp smtp Telnet
udp protocol: tftp dns
3. Application layer and session layer protocol:
NFS ：Network File System is a file system developed by the late Sun company for distributed access, and its essence is a file system.
Mainly in the Unix family of operating systems to use, based on TCP / IP protocol layer, a remote computer to a local disk can be mounted as a local disk the same operation.
On the basis of the transport layer protocol, there is a class instant messaging protocol , are more mature: Instant Messaging and Presence Protocol (IMPP), space and instant messaging protocol (PRIM), instant messaging and space balanced expansion process for the SIP protocol
( SIMPLE) and XMPP. There is also a new MQTT
Two, NetBEUI protocol
(1) The basic concept
NetBios Enhanced User Interface, or NetBios Enhanced User Interface. It is the NetBios protocol The enhanced version has been adopted by many operating systems, such as Windows for Workgroup, Win 9x series, Windows NT, etc.
The NETBEUI protocol is useful in many situations and is the default protocol for operating systems before WINDOWS98. The NetBEUI protocol is a short, compact, and highly efficient broadcast protocol. It does not need to be set after installation. It is especially suitable for
transmitting data in the "network neighbors". Therefore, it is recommended that in addition to the TCP/IP protocol, a computer on a small LAN can also install the NetBEUI protocol. Another point to note, if one only installed TCP / IP protocol WINDOWS98 machine in order to join
the WINNT domain, you must also install NetBEUI protocol.
(2)
Samba is a Windows file sharing protocol-CIFS implemented under Unix systems. Since Windows sharing is based on the NetBios protocol and a broadcast protocol based on Ethernet, it cannot be used across network segments without a transparent bridge (such as VPN) of. It is mainly used for file and printer sharing in unix and windows systems, and it can also be mounted locally for use through the program in the samba suite.