1. Unit 5: Providing Network Services
G10-Term1-2017/2018
Unit 5: Providing Network Services
How clients access internet services
how client and severs interact
Request web page
What happens when use a domain name
T. Shaikhah Sulaiman
Dibba Alfujairah Secondary School

2. how client and severs interact
server stores data and responds to requests for data or files such as web pages.
A server stores data to be used by other computers on a network. A server could be a specialized machine or it can be a normal PC running server software.
Client-server is the most common way to organize a LAN.
The server typically looks after:
• Logins and security
• File handling
• Printing
• Internet access

3. Request web page Web servers
There are millions of servers connected to the internet. They provide services such as web sites, , financial transactions, music downloads, etc
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, one or more floors, or an entire building. Data centers are typically very expensive to build and keep. For this reason, only large organizations use privately built data centers to house their data and provide

4. Serving web page

5. Serving web page

6. DNS
Domain Name System
DNS is a protocol for how computers exchange data
This is known as the TCP/IP protocol suite.
Translate the domain name to its IP address

7. 3- ROOT 1-DNS local cash 4-TLD 2- ISP 5-Get IP
What happens when use a domain name
3- ROOT
1-DNS local cash
4-TLD
2- ISP
5-Get IP

8. your computer looks is its local DNS cache,
DNS servers don’t have the answer,
2- computer queries (contacts) your ISP DNS servers.
DNS servers don’t have the answer,
3- they query the root name servers. A name server is a computer that answers questions about domain names, such as IP addresses. The thirteen root name servers
They don’t know the answer, but they can direct your query to someone that knows where to find it.
DNS servers don’t have the answer,
4- The TLD nameservers
directs your query to the nameservers responsible for this specific domain.
These authoritative nameservers are responsible for knowing all the information about a specific domain.
5- The server gets the IP address from the authoritative nameservers and stores the record in its local memory. If anyone else requests the host record for, the ISP servers will already have the answer

9. https://www.youtube.com/watch?v=mpQZVYPuDGU DNS
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