tcp ip ports and protocols

, to the end of the chain, or to all connections that are applied along the chain. Although figure 2-2 is linear, each participant may engage in multiple, concurrent communication. For example, B may receive a request from many clients without passing a, and/or send the request to a without C, at the same time it may also process a request.Any aggregation against non-as-a-channel may enable an internal cache for processing requests. The effect of caching is that the request/response chain is sho

fl_icmp_type plugin # define fl_icmp_code plugin # define fl_ipsec_spi plugin # define fl_mh_type plugin _ u32 secid;/* used by xfrm; see secid.txt */} _ attribute _ (_ aligned _ (BITS_PER_LONG/8 ))); From the above structure definition, we can see that a data packet's source and destination address ports have proto options, user-defined types, and even the inbound and outbound interfaces. Then, through these identifiers, you can uniquely determine

and Port numbersBoth TCP and UDP are IP-level transport protocols, which are the processing interfaces between IP and the upper layer. The TCP and UDP port numbers are designed to differentiate the IP addresses of multiple applic

Analysis of TCP/IP layer-4 protocol system and tcpip layer-4 Protocol TCP/IP layer-4 protocol system 1) The link layer, also known as the data link layer or network interface layer, usually includes the device driver in the operating system and the network interface card corresponding to the computer. They work togeth

This article mainly describes the Linux under the Iptables only allow the specified IP address to access the specified port setting method, the need for friends can refer to.First, clear all pre-settingsSecond, the settings allow only the specified IP address to access the specified portIptables-a input-s xxx.xxx.xxx.xxx-p tcp--dport3306Above two, note that the--

. This is different from the TCP protocol. UDP adds the port number and Verification Code parameters to the IP package. 　　 Port 6.1 　　 How does a client program on a computer reach the server? The communication lines of applications and UDP are the same through UDP ports. These ports are numbers, starting with 0. A por

. The IP addresses of the two hosts AND the subnet mask are used for the AND operation at the same time. If the result is the same, the two computers are in the same subnet AND can communicate directly. Domain Name composition: Host Name + organization name + network name + top-level domain name.The Core protocols of the transport layer are TCP and UDP.

1. IntroductionIP is the most central protocol in the family of TCP/IP protocols. All TCP, UDP, ICMP, and IGMP data are transmitted in an IP datagram format. IP provides unreliable, non-connected datagram delivery services.(1) unr

a connecting role.The main task of this layer is to provide users with reliable end-to-end error and flow control to ensure the correct transmission of the message. The function of the transport layer is to block the details of the lower layer data communication to the high level, i.e. transparently transmitting the message to the user. Common protocols for this layer are TCP

TCP/IP protocol (Transmission control protocol/internet Protocol Transmission Control Protocol/Internet Interconnection Protocol) TCP/IP is a protocol Stack, including TCP, IP, UDP, ICMP, RIP, TELNET, FTP, SMTP, ARP, and many othe

Transfer http://blog.csdn.net/goodboy1881/article/details/668556 ------------------------------------------------------ Put the three Protocols together for learning because these three protocols are on the same layer. ARP is used to find the MAC address of the Ethernet NIC of the target host, and the IP address carries the message to be sent. The data link layer

The TCP/IP protocol is actually a set of protocols, including many protocols, which constitute the TCP/IP protocol stack. But the Transmission Control Protocol (TCP) and the Internet Pr

TCP/IP Note 3. Transport Layer (1) -- UDP, TCP 1. Transport Layer 1.1 two Protocols: TCP and UDP. (1) TCP: provides a reliable data transmission service. TCP is connection oriented and

parameter problem (theIP header field is wrong), and the routing (change of path) is changed. 1.3.2. QueryThis is primarily used for loopback requests and responses (judging whether they are reachable), timestamp requests, and questions and answers (time synchronization) in both cases.1.4. ICMP Example1.4.1. PingDetermine if the destination host is reachable.1.4.2. TracertDisplays the routing path to which the destination host will pass.2.TCP(Interne

From the simplest of an HTTP request development, according to the TCP/IP protocol, separate the data frame structure of each layer, and how they assume the network service.Protocol stackThe Internet protocol stack consists of five layers:1. The application layer is where the network application and its application layer protocols persist. The application layer o

domain name online.NetBIOS over TCP/IP:NetBIOS is a network protocol that was developed jointly by IBM and Sytec in the early 80 's, for the so-called pc-network. Although there are few published documents, the API of the Protocol becomes a de facto standard.As Pc-network is replaced by Token Ring and Ethernet, NetBIOS should also exit the historical stage. However, because many software uses NetBIOS APIs, NetBIOS is adapted to a variety of other

Put these three protocols together because the three protocols are on the same level, the ARP protocol is used to locate the target host's Ethernet NIC MAC address, and the IP hosts the message to be sent. The data link layer can get the data transfer information from ARP, and the data to be transmitted from IP.1.

-IP protocols temporarily allocate port numbers between 1024~5000Port number greater than 5000 reserved port number for other servicesAbout the TCP protocolTCP is the most commonly used protocol for Transport layer, and it is also a more complex protocol.TCP establishes a link before the data is transferred and closes the link when the transmission endsTCP three-

Reproduced in: http://www.itxuexiwang.com/a/liunxjishu/2016/0225/167.html?1456482565As shown is the three stages of TCP. 1,TCP three handshake. 2,TCP data transfer. 3,tcp's four waves.SYN: (Synchronous sequence number, Synchronize Sequence Numbers) This flag is valid only when the three handshake is established. Represents a new

Introduction: This article as a theoretical basis, will tell us the basic principles of TCP/IP and important protocol details, and on this basis, introduced the implementation of TCP/IP on Linux.OSI Reference Model and TCP/IP Refe