Providing Network Services Unit . 5 Providing Network Services Prepared By: Shamsa Alhassouni
Lesson Objectives: Understand what happens when using a domain name Understand how clients and servers interact Understand how web pages are requested Understand what happens when using a domain name
How do clients and servers interact
All these services rely on Client and server interaction What are the routine services you use over networks Update social media status Send and receive Emails Online shopping Online Booking All these services rely on Client and server interaction
How client and severs interact One of the most common way to organize LAN is Client/Server Topology in which many clients will be connected to one end source. A server : is a high end computer running software application (web server) that provides services for the other hosts connected to the network Services includes: Logins and security File and printer sharing Security and management Internet access Web sites and email services Downloading of applications and music
Prepared By: Shamsa Alhassouni How client and severs interact There are different types of servers providing the different services Types of Servers Prepared By: Shamsa Alhassouni
Request A Web Page
Request a website : www.google.ae Clients running web browser software Request web page Request a website : www.google.ae Server responds carrying a Function: sending the requested document back to the client Clients running web browser software
Request web page Server Farm A web server : is usually in a part of the network with other servers called a server farm, or within a data center. A data center can take up one room or more floors, or an entire building. Data centers very expensive to build and keep. For this reason, only large organizations use privately built data centers to house their data and provide services to users
Serving up Webpage
Prepared By: Shamsa Alhassouni Serving up web pages when requesting a web page Uniform Resource Locator (URL) identifies the following: Protocol used (HTTP) Domain name Location of the resource on the server. Protocol Domain Name Folder Name File Name Prepared By: Shamsa Alhassouni
Prepared By: Shamsa Alhassouni Domain Name Service DNS : is a protocol for how computers exchange data on the internet and private networks This is known as the TCP/IP protocol suite. Its main job is to turn the domain name into IP address , its like a phone book. Prepared By: Shamsa Alhassouni
What happens when using a domain name 3. Root Servers Don’t Know 2. ISP Server Cashe memory 1 DNS Cache of client Request Request Request Don’t Know Request 4. TLD Servers Stores domain address information Domain Available IP Address is 74.125.44.25 4. Authoritative Name Servers Knows everything about domains including IP addresses Prepared By: Shamsa Alhassouni
Book Activity P-190 1 2 4 3