Explanation of the meanings of computer layers

Network protocols for each layer of the computer


Application layer: (Typical device: application, such as FTP,SMTP, HTTP)


The DHCP (Dynamic Host Configuration Protocol) dynamically host assignment protocol, which works with UDP protocol, has two main uses: to automatically assign IP addresses to internal networks or network service providers, For users or internal network administrators as a means of central management of all computers. Implement Plug and Play networking.

BOOTP (BOOTSTRAPPROTOCOL) bootloader Protocol/Bootstrap protocol, using UDP to enable a diskless workstation to obtain configuration information automatically. Static Configuration Protocol DNS (domain name System) domain name resolution < port number 53>

FTP (file Transfer Protocol) files Transfer Protocol < port number 21> reduce or eliminate the incompatibility of processing files under different operating systems.

Gopher (the Internet Gopher Protocol) Internetwork Gopher Protocol

HTTP (hypertext Transfer Protocol) Hypertext Transfer Protocol < port number 80&GT, transaction-oriented application layer protocol.

IMAP4 (Internet Message Access Protocol 4) version 4th of the Internet Information Access Protocol

IRC (Internet Relay chats) Network Chat protocol

NNTP (Network news Transport Protocol) Web Press Transfer Protocol

XMPP Extensible Message Processing Site Protocol

POP3 (Post Office Protocol 3) is the 3rd version of the Post Office Protocol, which is used to accept messages.

SIP () Signaling Control Protocol

SMTP (Easy Mail Transfer Protocol) Simple Mail Transfer Protocol < port number 25> used to send messages.

SNMP (Simple network Management Protocol), Simplified Web Management Protocol

SSH (Secure Shell) Secure Shell protocol

Telnet Remote Login Protocol < port number 23>

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 the UDP over NATs, NAT, UDP easy traversal) is a network protocol

NTP (Network time Protocol) Net-at-school protocol.


Transport Layer: (Typical device: process and port) data unit: Data segment (Segment)

The TCP (transmission Control Protocol) transmission protocol provides a reliable connection-oriented service, which must be established before the data is transferred and released. Reliable full-duplex channel. Reliable, orderly, no loss, no repetition.

UDP (user Datagram Protocol) User Datagram Protocol does not need to establish a connection before sending data, does not use congestion control, does not guarantee reliable delivery, maximum effort delivery.

DCCP (Datagram Congestion control Protocol) Datagram Congestion protocol

SCTP (Stream control transmission PROTOCOL) stream-controlled transport protocol

RTP (Real-time Transport Protocol) real-time Transfer Protocol

RSVP (Resource ReSer vation Protocol) Resource Reservation Protocol

PPTP (Point-to-Point tunneling Protocol) peer-to-Peer tunneling Protocol

Network layer: (Typical device: router, firewall, multilayer switch) data unit: Packet (Packet)

IP (IPv4 IPV6) (Internet Protocol) Network Interconnection Protocol

The ARP (address Resolution Protocol) is a resolution protocol that realizes its physical address through an IP address.

The RARP (Reverse address Resolution Protocol) Reverse address Translation 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) Internet Controlled message protocol. It is a sub-protocol of the TCP/IP protocol family that is used to pass control messages between IP hosts and routers.

ICMPV6:

The

 igmp (internet Group Management Protocol) Internet Groups Management Protocol, which is a multicast protocol in the   Network protocol family, is used for IP   hosts to report to any directly adjacent router and nbsp; report to their group members.   the

 rip (Router Information Protocol) Routing Information Protocol is a standard for exchanging routing information between a gateway and a host.  

OSPF (Open Shortest path Firs) Open Shortest Path First, Distributed Link State protocol.  

&NBSP;BGP (Border gateway Protocol) Border Gateway protocol, which is used to connect a routing protocol to a stand-alone system on the Internet. Route selection protocol using path vectors.  

 is-is (intermediate system to intermediate system Routing Protocol) The routing protocol for Intermediate systems to intermediate systems.  

 ipsec (IP Secure) Internet   Protocol security is an open-standard framework that uses encrypted security services to ensure that Internet   Protocol (IP)   Confidential and secure communication on the network.  


Data Link layer: (Typical device:   network card, bridge, switch)             data unit: Frame  

Arq (Automatic repeat-request) automatic retransmission request protocol, one of the error correction protocol, including the Stop Wait Arq protocol and continuous ARQ protocol, error detection, positive confirmation, over-time retransmission and negative confirmation relay to re-transmission and other mechanisms. &NBSP

  Stop wait Protocol:  
&NBSP;CSMA/CD (Carrrier sense multiple Access with collision Detection) Carrier monitor multipoint access/ Collision Detection Protocol. General line Network, the essence of the Protocol is carrier monitoring and collision detection. The carrier monitoring is to send data before the detection of the bus on the other computers in the transmission of data, such as temporarily do not send data, to avoid collisions. Collision detection for the computer side to send data edge detection channel signal voltage size.   the

PPP (point-to-ponit Protocol) point-to-Point protocol is byte-oriented and consists of three parts: A method for encapsulating an IP datagram to a serial link, and a Link control protocol for establishing, configuring, and testing a data link connection

LCP (Link control Protocol): A set of network control Protocol NCP.

The HDLC (High-level Data Link Control) Advanced data link controls the synchronous transmission of data over the network and the bit-oriented data Link layer protocol.

ATM (asynchronous Transfer mode) Asynchronous transfer method, based on circuit switching and packet switching on the basis of a connection-oriented fast packet switching technology. "Async" means "asynchronously inserting" an ATM cell into a synchronous SDH bitstream. If the synchronization is inserted, the time slot occupied by the user in each frame is fixed in relative position. "Synchronization" means that the bitstream on each link in the network is controlled by the same very precise master clock. Wi-Fi, WiMAX, DTM, Token Ring, Ethernet, FDDI, Frame Relay, GPRS, EVDO, HSPA, L2TP, ISDN

Physical layer: (Typical device: Repeater, hub, network cable, hub) data unit: bit (bit)

Ethernet physical layer, modem, PLC, SONET/SDH, g.709, optical fiber, coaxial cable, twisted pair

Finally, we enclose a diagram of each layer of protocol:

Explanation of the meanings of computer layers