Internet Protocol This article is about the IP network protocol only. For Internet architecture or other protocols, see Internet protocol suite. The Internet Protocol (IP) is the principal communications protocol in the Internet protocol suite for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet. Historically, IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974; the other being the connection-oriented Transmission Control Protocol (TCP). The first major version of IP, Internet Protocol Version 4 (IPv4), is the dominant protocol of the Internet. Function The Internet Protocol is responsible for addressing hosts and for routing datagrams (packets) from a source host to a destination host across one or more IP networks. Datagram construction Sample encapsulation of application data from UDP to a Link protocol frame Reliability
List of TCP and UDP port numbers Wikipedia list article This is a list of TCP and UDP port numbers used by protocols for operation of network applications. The (IANA) is responsible for maintaining the official assignments of port numbers for specific uses. However, many unofficial uses of both well-known and registered port numbers occur in practice. Table legend Well-known ports The port numbers in the range from 0 to 1023 (0 to 210 − 1) are the well-known ports or system ports. They are used by system processes that provide widely used types of network services. Registered ports The range of port numbers from 1024 to 49151 (210 to 214 + 215 − 1) are the registered ports. Dynamic, private or ephemeral ports The range 49152–65535 (215 + 214 to 216 − 1) contains dynamic or private ports that cannot be registered with IANA. This range is used for private or customized services, for temporary purposes, and for automatic allocation of ephemeral ports. See also References and notes
S-T: Http Request/Response Anatomy Introduction to Web Web consist of billion of clients and server connected through wires and wireless networks. The web clients makes request to web server. The web server receives the request, finds the resources and return response to the client. Web Application A web site is a collection of static files such as HTML pages, images, graphics etc. HTTP is a protocol that clients and server uses on the web to communicate.It is similar to other internet protocol such as SMTP(Simple Mail Transfer Protocol) and FTP(File Transfer Protocol) but there is one fundamental difference.HTTP is a stateless protocol i.e HTTP supports only one request per connection.This means that with HTTP the clients connects to the server to send one request and then disconnects. HTTP method HTTP request can be made using a variety of methods, but the ones you will use most often are Get and Post. HTTP Method and Descriptions Difference between GET and POST request Anatomy of an HTTP GET request
PHP server-side scripting language PHP: Hypertext Preprocessor (or simply PHP) is a server-side scripting language designed for Web development. It was originally created by Rasmus Lerdorf in 1994; the PHP reference implementation is now produced by The PHP Group. PHP originally stood for Personal Home Page, but it now stands for the recursive initialism PHP: Hypertext Preprocessor. The standard PHP interpreter, powered by the Zend Engine, is free software released under the PHP License. The PHP language evolved without a written formal specification or standard until 2014, with the original implementation acting as the de facto standard which other implementations aimed to follow. History Early history PHP development began in 1994 when Rasmus Lerdorf wrote several Common Gateway Interface (CGI) programs in C, which he used to maintain his personal homepage. PHP/FI could be used to build simple, dynamic web applications. PHP 3 and 4 PHP 5 <!
Application layer Although both models use the same term for their respective highest level layer, the detailed definitions and purposes are different. In the OSI model, the definition of the application layer is narrower in scope. The OSI model defines the application layer as the user interface responsible for displaying received information to the user. TCP/IP protocols The IETF definition document for the application layer in the Internet Protocol Suite is RFC 1123. Remote login to hosts: TelnetFile transfer: File Transfer Protocol (FTP), Trivial File Transfer Protocol (TFTP)Electronic mail transport: Simple Mail Transfer Protocol (SMTP)Networking support: Domain Name System (DNS)Host initialization: BOOTPRemote host management: Simple Network Management Protocol (SNMP), Common Management Information Protocol over TCP (CMOT) Other protocol examples References External links
HTTP: The Protocol Every Web Developer Must Know - Part 2 In my previous article, we covered some of HTTP's basics, such as the URL scheme, status codes and request/response headers. With that as our foundation, we will look at the finer aspects of HTTP, like connection handling, authentication and HTTP caching. These topics are fairly extensive, but we'll cover the most important bits. A connection must be established between the client and server before they can communicate with each other, and HTTP uses the reliable TCP transport protocol to make this connection. HTTPS is a secure version of HTTP, inserting an additional layer between HTTP and TCP called TLS or SSL (Transport Layer Security or Secure Sockets Layer, respectively). An HTTP connection is identified by <source-IP, source-port> and <destination-IP, destination-port>. resolve IP address from host name via DNSestablish a connection with the serversend a requestwait for a responseclose connection The server is responsible for always responding with the correct headers and responses.
File Transfer Protocol FTP is built on a client-server architecture and uses separate control and data connections between the client and the server. FTP users may authenticate themselves using a clear-text sign-in protocol, normally in the form of a username and password, but can connect anonymously if the server is configured to allow it. For secure transmission that hides (encrypts) the username and password, and encrypts the content, FTP is often secured with SSL/TLS ("FTPS"). SSH File Transfer Protocol ("SFTP") is sometimes also used instead, but is technologically different. History The original specification for the File Transfer Protocol was written by Abhay Bhushan and published as RFC 114 on 16 April 1971. Until 1980, FTP ran on NCP, the predecessor of TCP/IP. The protocol was later replaced by a TCP/IP version, RFC 765 (June 1980) and RFC 959 (October 1985), the current specification. Protocol overview Communication and data transfer ASCII mode: used for text. Login or:
Request–response Request–response or request–reply is one of the basic methods computers use to communicate to each other. When using request–response, the first computer sends a request for some data and the second computer responds to the request. Usually there is a series of such interchanges until the complete message is sent. Browsing a web page is an example of request–response communication. One can think of request–response as being like a telephone call, where you call someone and they answer the call. Compare this with one-way computer communication, which is like the push-to-talk or "barge in" feature found on some phones and two-way radios, where a message is sent without waiting for a response. Technical details Request–response, also known as request-reply, is a message exchange pattern in which a requestor sends a request message to a replier system which receives and processes the request, ultimately returning a message in response. See also References
Cascading Style Sheets CSS is designed primarily to enable the separation of document content from document presentation, including elements such as the layout, colors, and fonts. This separation can improve content accessibility, provide more flexibility and control in the specification of presentation characteristics, enable multiple pages to share formatting, and reduce complexity and repetition in the structural content (such as by allowing for tableless web design). CSS can also allow the same markup page to be presented in different styles for different rendering methods, such as on-screen, in print, by voice (when read out by a speech-based browser or screen reader) and on Braille-based, tactile devices. It can also be used to allow the web page to display differently depending on the screen size or device on which it is being viewed. CSS specifies a priority scheme to determine which style rules apply if more than one rule matches against a particular element. Syntax Selector Use
Telnet Telnet is a network protocol used on the Internet or local area networks to provide a bidirectional interactive text-oriented communication facility using a virtual terminal connection. User data is interspersed in-band with Telnet control information in an 8-bit byte oriented data connection over the Transmission Control Protocol (TCP). Telnet was developed in 1968 beginning with RFC 15, extended in RFC 854, and standardized as Internet Engineering Task Force (IETF) Internet Standard STD 8, one of the first Internet standards. Historically, Telnet provided access to a command-line interface (usually, of an operating system) on a remote host. History and standards Before March 5, 1973, Telnet was an ad hoc protocol with no official definition. Essentially, it used an 8-bit channel to exchange 7-bit ASCII data. Security It is of note that there are a large number of industrial and scientific devices which have only Telnet available as a communication option. Telnet 5250
Web Services Description Language The Web Services Description Language (WSDL) is an XML-based interface description language that is used for describing the functionality offered by a web service. The acronym is also used for any specific WSDL description of a web service (also referred to as a WSDL file), which provides a machine-readable description of how the service can be called, what parameters it expects, and what data structures it returns. It thus serves a purpose that corresponds roughly to that of a method signature in a programming language. The current version of WSDL is WSDL 2.0. The meaning of the acronym has changed from version 1.1 where the D stood for Definition. Description Representation of concepts defined by WSDL 1.1 and WSDL 2.0 documents. The WSDL describes services as collections of network endpoints, or ports. Example WSDL file <? History WSDL 1.0 (Sept. 2000) was developed by IBM, Microsoft, and Ariba to describe Web Services for their SOAP toolkit. See also References
Port (computer networking) In computer networking, a port is a software construct serving as a communications endpoint in a computer's host operating system. A port is always associated with an IP address of a host and the protocol type of the communication. It completes the destination or origination address of a communications session. Specific, well-known port numbers are often used to identify specific applications and services. In the client-server model of application architecture, ports are used to provide a multiplexing service on each port number that network clients connect to for service initiation, after which communication is reestablished on another connection-specific port number. Transport Layer protocols, such as the Transmission Control Protocol (TCP) and the User Datagram Protocol (UDP), specify a source and destination port number in their packet headers. The core network services, such as the World-Wide Web, typically use small port numbers less than 1024. Examples include: