CS511-Web Engineering

Week 1

Topic 5-6

CS511-Week 1:Topic 5-6
CS511-Week 1:Topic 5-6


Topic 5:

Client-server model:
The web is  referred to as a client-server model of communications. There are two types of actors in the  client-server model: 
  1. clients 
  2. servers 
Server:
The server is a computer that is normally active 24/7, listening for requests from clients.
Client:
A client refers to a computer that sends requests to a server and receives responses in return.
Server Types: 
Different types of Severs such as,
  1. Web servers
  2. Application servers
  3. Database servers
  4. Mail servers
  5. Media servers
  6. Authentication servers

Web server:
A computer that handles HTTP requests is called a web server.
Application servers:
A computer designed to run and manage web applications is called an application server.
Database servers:
A computer that is dedicated to running a Database Management System (DBMS) is referred to as a database server.
Mail servers:
A mail server is a computer responsible for sending, receiving, and processing email messages.
Media servers:
A media server, which is also known as a streaming server, is a specialized type of server designed to serve requests for images and videos.
Authentication servers:
The primary security needs of web applications are commonly handled by an authentication server.
Server Farms:
Server farms aim to distribute incoming requests among groups of machines in order to avoid overwhelming a single web or data server.
Server Racks:
A server farm will consist of many server racks.
Data Centers:
A data center will contain:
  1. Computers
  2. Hard drives
  3. Sophisticated air conditioning systems
  4. Redundancy 
  5. Power Systems 
  6. Using batteries and 
  7. Generators
  8. Specialized fire suppression systems 
  9. Security personnel 
These are all part of a typical data center.

Assessment:

  • Normally, a web developer focuses on servers and their configurations. 

  1. True
  2. False

  • Suppose a webpage has a .htm or .html extension. It is most of the time.

    1. Training page
    2. Static page
    3. Dynamic page
    4. Moving page

Topic 6:

Internet from Home to ISP:
The broadband modem, also known as a cable modem or DSL modem, acts as a bridge between the network hardware located outside the home (typically controlled by a cable or phone company) and the network hardware within the home. The wireless router is often the most visible aspect of the Internet within a household. 

Neighborhood broadband cables are combined and linked to fiber optic cables via fiber connection boxes. 
These fiber optic cables eventually reach an ISP's head-end, which is a facility that may include a cable modem termination system (CMTS) or a digital subscriber line access multiplexer for DSL-based systems.

Routing Tables:
The flow of internet traffic is carried out mainly by routers. A router is a hardware device are responsible for forwarding data packets between networks. As a packet enters a router, it is analyzed to determine its destination address, and the router then directs the packet towards its intended destination. In order to make these decisions, routers rely on a routing table that helps them where a packet should be sent.

Assessment:

  • ________contents cannot change at run time.

    1. Office web page
    2. Dynamic web page
    3. Static web page
    4. X.25 web page

 The End😊