OSI seven-layer model and related protocols

1. Model

Physical Layer:
converts data into electronic signals that can be transmitted through physical media equivalent to a porter in the post office. The
passes the media transfer bits, providing the mechanical and electrical specifications. The
mainly defines the physical device standards, such as the interface type of the network cable, the interface type of the fiber, the transmission rate of various transmission media, etc. Its main role is to transmit the bitstream (that is, from 1, 0 to the current strength to carry out the transmission, after reaching the destination in the conversion to 1, 0, which is what we often call the digital-to-analog conversion and the ADC), the layer of data called bits.
Data Link layer:
This layer frames the data and handles flow control. This layer specifies the topology and provides hardware addressing. Equivalent to a loading and unpacking worker in a post office. The
defines how to make data formatted for transmission and how to control access to physical media, which often also provides error detection and correction to ensure reliable data transmission.
Network layer:
provides connectivity and path selection between two host systems located in geographically diverse networks, and the development of the Internet has greatly increased the number of users accessing information from every site in the world, and the network layer is the layer that manages this connection.
Transport Layer:
provides port-to-port connectivity. (after masking the lower layer, it can be understood that communication between the ports)
defines some protocol and port number for transmitting data (WWW port 80, etc.), such as: TCP (Transmission Control Protocol, low transmission efficiency, high reliability, for transmission reliability requirements, data volume of large data), UDP (User Datagram Protocol, Contrary to the TCP characteristics, for transmission reliability requirements are not high, data volume of data, such as QQ chat data is transmitted through this way, the main is to be received from the lower layer of data segmentation and transmission, to the destination address and then reorganization, often this layer of data called a segment.
Session Layer:
Establish, manage, and terminate sessions. That is, through the transport Layer (port number: Transport port and receive port) to establish the path of data transmission, mainly between your system to initiate a session or accept a session request (between the devices need to know each other can be IP or Mac or host name).
Presentation layer:
For data conversion, compression, and encryption. The
ensures that the information sent by the application layer of one system can be read by the application layer of the other system. For example, a PC program communicates with another computer, where one computer uses an extended 210 binary Interchange Code (EBCDIC) and the other uses the U.S. Information Interchange Standard Code (ASCII) to represent the same characters. If necessary, the presentation layer enables conversion between multiple data formats by using a pass-through format.
Application layer:
is the OSI layer closest to the user, a layer that provides network services for user applications such as e-mail, file transfer, and terminal emulation.

Data transmission

Common protocols:
Network layer:
IP (Ipv4,ipv6): The transport mechanism used by the TCP/IP protocol family at the network layer is an unreliable, non-connected datagram protocol, a service that is nearly the largest effort to deliver. Try your best: The IP packet may be damaged, lost, out of sequence or delayed, and may cause network congestion. Lack of error control and auxiliary mechanisms (ICMP resolution). If you need to be reliable, rely on the TCP protocol.
ARP Resolution Protocol: Address Resolution Protocol-maps the logical address (IP address) from the IP protocol to the corresponding physical address, and then gives the physical address to the data Link layer for Mac encapsulation.
RARP (Reverse address Resolution Protocol): Reverse Resolution Protocol-allows the physical machine on the LAN to request its IP address from the Gateway server's ARP table or cache.
ICMP (Internet Control Message Protocol) Inter-protocol-error control and auxiliary mechanism for IP protocol, which is a sub-protocol of the TCP/IP protocol family, which is used to pass control messages between IP hosts and routers.
IGMP: (Internet Group Management Protocol) is a multicast protocol in the Internet Protocol family that is used by IP hosts to report their group members to any directly adjacent router.
Unicast routing protocol (RIP,OSPF and BGP)
RIP: Routing Information Protocol
OSPF: Open Shortest Path First protocol
BGP: Boundary Network Management Protocol, a routing protocol used to connect a standalone system on the Internet.
Is-is: (Intermediate system to intermediate system Routing Protocol) The routing protocol for Intermediate systems to intermediate systems.
IPSEC: Internet protocol security is an open-standard framework that ensures secure and confidential communication over Internet Protocol (IP) networks by using encrypted security services.
Transport Layer:
TCP (transmission Control Protocol) transmission protocol.
UDP (user Datagram Protocol) Subscriber Datagram Protocol
DCCP (Datagram Congestion control Protocol) Datagram Congestion protocol
SCTP (Stream control transmission PROTOCOL) stream-controlled transport protocol
RTP (Real-time Transport Protocol or abbreviated RTP) real-time Transfer Protocol
RSVP (Resource ReSer vation Protocol) Resource Reservation Protocol
PPTP (Point-to-Point tunneling Protocol) peer-to-Peer tunneling Protocol
Application layer:
DHCP (Dynamic Host Allocation protocol)
DNS (domain name resolution)
FTP (file Transfer Protocol) files Transfer Protocol
Gopher (English original meaning: the Internet Gopher Protocol Chinese Interpretation: (RFC-1436) Internet Gopher Protocol)
HTTP (hypertext Transfer Protocol) Hypertext Transfer Protocol
IMAP4 (Internet Message Access Protocol 4) is the 4th version of the Internet Information Access Protocol
IRC (Internet Relay chats) Network Chat protocol
NNTP (Network news Transport Protocol) RFC-977) Web Press Transfer Protocol
XMPP Extensible Message Processing Site Protocol
POP3 (Post Office Protocol 3) is the 3rd version of the Post Office Protocol
SIP Signaling Control Protocol
SMTP (Simple Mail Transfer Protocol) that is simply the message Transfer Protocol
SNMP (Simple network Management Protocol, simplified Web Management Protocol)
SSH (Secure Shell) Secure Shell protocol
Telnet Remote Login Protocol
RPC (remote Procedure call Protocol) (RFC-1831) Remoting protocol
RTCP (RTP control Protocol) RTP Controller protocol
RTSP (real Time streaming Protocol) live Streaming protocol
TLS (Transport Layer Security Protocol) secure Transport Layer protocol
SDP (Session Description Protocol) conversation Description Protocol
SOAP (Simple Object access Protocol) Basic Objects Access Protocol
GTP Universal Data Transmission Platform
STUN (simple traversal of UDP over Nats,nat) is a network protocol
NTP (Network time Protocol) networking protocol

OSI seven-layer model and related protocols