i) Layer 1 : Physical Layer
The first layer of the seven layers of Open Systems Interconnection (OSI) network model is called the Physical layer. Physical circuits are created on the physical layer of Open Systems Interconnection (OSI) model.Physical layers describe the electrical or optical signals used for communication.Physical layer of the Open Systems Interconnection (OSI) model is only concerned with the physical characteristics of electrical or optical signaling techniques which includes the voltage of the electrical current used to transport the signal, the media type (Twisted Pair, Coaxial Cable, Optical Fiber etc), impedance characteristics, physical shape of the connector, Synchronization etc.
Layer 2 : Datalink Layer
The second layer of the seven layers of Open Systems Interconnection (OSI) network model is called the Datalink layer. The Data Link layer resides above the Physical layer and below the Network layer. Datalink layer is responsible for providing end-to-end validity of the data being transmitted. The Data Link Layer is logically divided into two sublayers, The Media Access Control (MAC) Sublayer and the Logical Link Control (LLC) Sublayer.
Layer 3: Network Layer
The third layer of the seven layers of Open Systems Interconnection (OSI) network model is the Network layer. The Network layer of the OSI model is responsible for managing logical addressing information in the packets and the delivery of those packets to the correct destination. Routers, which are special computers used to build the network, direct the data packet generated by Network Layer using information stored in a table known as routing table.
Layer 4 : Transport Layer
The fourth layer of the seven layers of Open Systems Interconnection (OSI) network model is the Transport layer. The Transport layer handles transport functions such as reliable or unreliable delivery of the data to the destination. On the sending computer, the transport layer is responsible for breaking the data into smaller packets, so that if any packet is lost during transmission, the missing packets will be sent again.
Layer 5 : Session Layer
Session layer is the fifth layer of seven layered Open Systems Interconnection (OSI) Model.The position of Session Layer of the Seven Layered Open Systems Interconnection (OSI) model is between Transport Layer and the Presentation Layer.The session layer is responsible for establishing, managing, and terminating connections between applications at each end of the communication.
In the connection establishment phase, the service and the rules (who transmits and when, how much data can be sent at a time etc.) for communication between the two devices are proposed. The participating devices must agree on the rules. Once the rules are established, the data transfer phase begins. Connection termination occurs when the session is complete, and communication ends gracefully.
Layer 6 : Presentation Layer
The position of Presentation Layer in seven layered Open Systems Interconnection (OSI) model is just below the Application Layer. When the presentation layer receives data from the application layer, to be sent over the network, it makes sure that the data is in the proper format. If it is not, the presentation layer converts the data to the proper format. On the other side of communication, when the presentation layer receives network data from the session layer, it makes sure that the data is in the proper format and once again converts it if it is not.
Layer 7 :Application Layer
The Application Layer the seventh layer in OSI network model. Application Layer is the top-most layer of the seven layered Open Systems Interconnection (OSI) network model. Real traffic data will be often generated from the Application Layer. This may be a web request generated from HTTP protocol, a command from telnet protocol, a file download request from FTP protocol etc.
ii) Client Side Code:-Software
that is downloaded from Web server to browser and then executes on the client.
Server Side Code : -Software that runs on the server,
not the client: Receives input from,URL parameters,HTML form data•Cookies,HTTP headers.
-Can access server-side databases,
e-mail servers, files, mainframes, etc.
-Dynamically builds a custom HTML
response for a client
Differences: -
Server Side Code :
-It is written in the .CS file for C# and .vb file for VB.Net.
-Server side code will always run on server side and create round trip on server in the response of request for any aspx page.
-These will consume the servers memory.
-server side code validate data to check whether sent data is correct or not.
Client Side Code :
-It is a scripting language (JavaScriptpt or vb script) that can be included in the HTML Page or can contain in the Source File either .vb or .cs .
-It runs on client's browser it does not create any round trip to the server.
e.g validation of controls dynamically hiding and displaying some of controls or there values etc.
-The reason why we do client side validations is to save the to and from time taken for the request to go to the server and the response to get back to the browser.
-Client side code validate the data before sending it to server.
iii)
Web Application:
-Web application or web app is any application software that runs in a web browser or is created in a browser-supported programming language (such as the combination of JavaScript, HTML and CSS) and relies on a common web browser to render the application.
Web Services:
-A programmable application component
accessible via standard Web protocols.
-Built on existing and emerging standards ( HTTP,
XML, SOAP, UDDI, WSDL)
-Server-based application which may be
accessed over the web via HTTP, but is meant
primarily for interaction with other programs.
