layer 2 tunneling protocol

server via the HTTP protocol, which is now the most frequently used application layer protocol.The principle is simple: After clicking on a link, the browser initiates a TCP connection to the server; After the connection is established, the browser sends the HTTP request message, and the server responds to the message. The content of the response message received by the browser is displaye

The 7 layers of the OSI are from top to bottom, respectively:7 应用层 6 表示层 5 会话层 4 传输层 3 网络层 2 数据链路层 1 物理层Among the high-level, the 7, 6, 5, 4 layers Define the functionality of the application, the following 3 layers, both 3, 2, and 1 are primarily oriented toward end-to-end data flows through the network. Let me introduce you to this 7-layer function:(1) Applicat

technical management, and these routers use an as internal routing selection protocol and a common measurement to determine the routes grouped in the, in addition, a routing protocol between as is used to determine the routing between groups in. Status quo: Although an as uses a variety of internal routing selection protocols and metrics, it is important that an as shows a single and consistent routing str

Receiving matching function _ napi_gro_receive (napi, skb) of The Link Layer ): This function matches messages and does not merge messages. The matching rule must meet both of the following conditions ): 1. The received dev packets must be the same. 2. The two packets must have the same Ethernet header. Static int _ napi_gro_receive (struct napi_struct * napi, struct sk_buff * skb) {struct sk_buff * p;/* t

transmission will improve the user's experience.Summarize:1. What is the role of the confirm identifier bit in the TCP header?2. What identity bits in the TCP header participate in the TCP three handshake?For:1. The ACK flag bit in the TCP header is used to confirm the data received by the destination end. After the destination has successfully received the byte with the sequence number x and all previous bytes, it is confirmed with the serial number

Bluetooth protocol (2) specifications of the Bluetooth protocolChapter 2 Bluetooth protocol specifications (RF, baseband Link Control, and link management) The Bluetooth protocol is a rule for information exchange between bluetooth devices. Like the Open Systems Interconnec

The application layer protocol at the top of the protocol stack defines how application processes running on different end systems pass messages to each other. The definition reads as follows:1. Type of message exchanged. Request messages and response messages.2, various types of message syntax, such as the various fie

The introduction to IPTABBLES+L7 is divided into two parts: The first part —————— to the system upgrade L7 patch The second part —————— the application of IPTABLES+L7 The first part: the system upgrades patching In order to use the L7 layer protocol for control, we need to patch files in the kernel, the kernel file needs to be recompiled, each of the following steps need to be cautious, or to start agai

About portsCommunication between any two hosts on the internet is from one end to the other, also known as end-to-end communication.What is a port?Modern operating systems are equipped with many applications, information to my computer how do I know this message is passed to my QQ application? My QQ program is responding but my MSN did not respond to it?The reason: My system has a number of port numbers, each application process is bound to a unique local port number, so that each program is bou

network bottleneck problem caused by the low speed and complexity of the traditional router. L2 Switch communication process Assume that two sites A and B that use the IP protocol communicate with each other through the L2 Switch. When sending Site A, they will first compare their IP addresses with the IP addresses of site B, determine whether Site B is in the same subnet as itself. If the destination site B and the destination site A are in the same

source location is the local MAC address, we can obtain it from the MAC address of the local Nic. The type indicates the upper-layer protocol type. ARP is used here and 0x0806 indicates the complete frame encapsulation. ARP header data filling: There are many types of hardware, that is, there are a variety of hardware types, such as the ethernet card, card ring network card, etc., 0x0001 indicates the eth

1 PrefaceThere are few articles on the internet about HTTPS, and there is little to share in the practical experience of deploying HTTPS at large Internet sites, and we have a lot of doubts about deploying HTTPS.This article for you to introduce the practice of Baidu HTTPS and some trade-offs, hoping to give a chance.This article was first published in the Baidu Operations and maintenance Department official blog2 Practice work outside the protocol

HTTP (Hypertext Transfer Protocol), RTSP (Real time Streaming protocol live streaming protocol), RTMP (Routing Table Maintenance Protocol Routing Tables Maintenance Protocol) is the application layer

HTTP (Hyper-Text Transfer Protocol), RTSP (Real Time Streaming protocol live Stream Transfer Protocol), RTMP (Routing Table Maintenance Protocol Routing Tables Maintenance Protocolis the application layer protocol, theoretically c

Transferred from: Http://bbs.ednchina.com/BLOG_ARTICLE_172024.HTM2.4-Block Transport protocol T=1In the T=1 protocol, commands, R-APDU, and Transmission control information (such as acknowledgment information) transmitted between the TAL and IC cards are made up of blocks.The following defines the block frame structure of the data link layer, special options for

device is responsible for initializing, controlling, and terminating the interaction with the slave device or the burst mode device. The primary device is divided into the primary device and the secondary master device to use the two primary devices at the same time on the HART communication link, the same Protocol rules must be used for primary and secondary primary devices in addition to the time limit for separating them. The primary device usuall

malicious attack. Most firewalls now know SYN/FIN packets, and some other combinations, such as SYN/FIN/PSH, SYN/FIN/RST, SYN/FIN/RST/PSH. Obviously, when such a package appears on the network Your network must have been attacked. Other known illegal packages include FIN (no ACK mark) and NULL. As discussed earlier, because ACK/FIN packets are generated to close a TCP connection, normal FIN packets always contain ACK Mark. A "NULL" packet is a packet without any TCP flag (URG, ACK, PSH, RST

the route cache (based on IP addresses, TOS, physical network devices, etc. If not, discard the group) and set DST for sk_buff. Data Packet processing is determined based on DST: Forwarding ip_forward (), local ip_local_deliver (), error ip_error (); 2 upper-layer protocol interfaces, such as TCP/UDP . This part can be viewed as sending. for TCP, ip_queue_x

layer-2 switch or a layer-3 Router The basic function of a vswitch is to receive data packets on the receiving port, select the output port, and send the data packets. How to select an output port depends on the type of the switch. The L2 Switch uses the MAC address of the data link layer to determine the outpu

segment is divided in the LAN, and solves the network bottleneck problem caused by the low speed and complexity of the traditional router. Layer 2 switch communication process Assume that two sites A and B that use the IP protocol communicate with each other through the L2 Switch. When sending Site A, they will first compare their IP addresses with the IP addres