application layer gateway sip

always built inside any gateway. Because as a well-known Application layer protocol, HTTP has its own set of standards at all levels, and everyone recognizes these standards. Using UDP You must implement a common-sense connection expiration mechanism, because at the UDP level it is impossible to identify a "connection" disconnection, which means that either the

IntroductionHTTP is an object-oriented protocol belonging to the application layer, which is suitable for distributed hypermedia information System because of its simple and fast way. It was proposed in 1990, after several years of use and development, has been continuously improved and expanded. Currently used in the WWW is the sixth edition of Http/1.0, http/1.1 standardization work is in progress, and Ht

information used to describe the browser, server, or message body. (3) Entity body: The entity body is usually not used in the request message. The Method field of the request message is the operation on the requested object, and the status code of the response message is a 3-digit number, divided into 5 classes of 33 kinds: 1xx indicates notification information, such as received or being processed. 2xx indicates successful reception. 3xx indicates redirection. 4x

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 protocol, Theoretically all can do live, on-demand, in fact, live more than rtmp and RTSP, on-demand is more use RTSP and HTTP.First, common areas: HTTP (HTTPS) all data as text processing, widely used

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 can do live, on-demand, in fact, live more than rtmp and RTSP, on-demand and more with RTSP and HTTP. First, common areas: HTTP (HTTPS) all data as text processing, widely

Note: The latest project will test the bandwidth between any two nodes in the network. I have found a lot of information and read many articles on csdn. I still have no clue. I couldn't think of a better way. I was depressed and thought about it for a long time. Repost this article to see how it is implemented. ZZ from http://blog.ouc.edu.cn/netdata/ ========================================================== ========================================================== ===== Chinese name: netiq cha

application-aware firewalls with other network security firewalls To achieve a balance, the company can install a specific firewall on different network layers. Low-level network firewalls can filter a large amount of bundled traffic, such as cache port scanning, denial of service, and other low-level network attacks. Understand the current fine-grained policies of complex Web applications through applications, allowing user traffic to pass through a

process of obtaining the IP address corresponding to the host name through the host name is called domain name resolution (or host name resolution ). The DNS protocol runs on the UDP protocol and uses the port number 53. HTTP: This is the most widely used protocol. It is often referred to as "Hypertext Transfer Protocol ". When browsing the Web page online, you have to open port 80 on the computer that provides web page resources to provide services. This port is often used for "WWW Service" a

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 fields in the message and how these fields are d

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domain name structure: the label in the domain name consists of English letters and numbers, each identifier is not more than 63 characters. A full domain name consisting of multiple labels is limited to a total of 255 characters. ------------------------------------------------------------------------------------- Hypertext Transfer Protocol Http:hypertext Transfer Protocol It is a kind of request/response protocol on the application

message, the start line is called the status line . Each of the three fields in the start line is separated by a space, and the CRLF at the end indicates carriage return and line wrapping. First line: Some information used to describe the browser, server, or message body. Entity Principal: The entity principal is not normally used in request messages. The Method field of the request message is the operation on the requested object, and the status code of the response message is a 3

# # #HTTPBrother-: The Transport Layer protocol uses TCP by defaultSmall knowledge:1. The server is being asked to set the address of the proxy server itself. Each request from the client is sent directly to the proxy server, and the proxy server requests the target resource (the LAN machine commonly used in the firewall to access the Internet or XXX is using forward)2. The reverse proxy is set on the server side. The client does not need to make any