FOC - B01

                     Computer network and hardware essentials

       Network Communication

Kilobit is used to measure the amount of data transferred per second. Kilobits per second is shortened to kb/s, Kbps or kbps (as opposed to Kbps which is Kilobytes per second). 

the lowercase b is commonly used to denote bits, and the other Uppercase B is used foe bytes

K stands for 1024 ....210(2 power 10)

k stands for 1000.....103(10 power 3)

1 kbps = 1000 bits per second

1 KBps = 1024 bytes per second

 

  • So an internet speeds of 512kb/s can never achieve  download speed of 512KB/s
  • formula to calculate the maximum download is [ download KB/s speed =( kb/s value*1000/8)/1024.

     Components of network


 Hardware Component

NIC= Network Interface card- is hardware components that physically connects computer and network 

 

network medium is a cable that plugs into the NIC and makes the connection between the computer and the rest of the network.

interconnecting device allows multiple devices to connect and communicate within the network


Software Component

Network and client servers

Network client servers e.g. Chrome web browser

Network server software e.g. Apache web 

Protocols

NIC driver




 

How 2 computers Communicate on a LAN

TCP/IP is most common protocol used on networks.

Logical address (IP address)=your name

Physical address (MAC address)=postal address


CIDR (classless inter domain routing) a single IP address can be used to designate to many unique IP address with CIDR

Broadcast IP address is an IP address that is used to send a message or packets to all the devices on a network.


Two computers Communicate on LAN 







  Network Terminology

Its a description of how devices can communicate with the network.



PANs

Personal Area Network is a group of network devices that allow communication between various connected devices.






LANs  

Local Area Network (LAN)-It is a group of network devices that allow communication between various connected devices.

  LAN has a short propagation delay than MAN as well as WAN.

 Which covers smaller areas such as colleges, schools , hospitals and so on.


MANs (Metropolitan area network)

A mans is a network that spans a large area, such as a town or city.


Internet

A world wide network which uses protocols such as TCP/Ip and http to transfer and view information.


Intranet

It is a private network which devices and servers are only available to those users connected to the internal network.

Extranet 

It  allows limited and controlled access to internal resources by outside users.


Public IP address vs Private IP address

IP address is a unique address that identifies a devices on the internet or local network.

The main differences between them is how far they reach, and what they're connected to.

The public IP address  is an IPv4 address that is reachable from the internet .

Private IP addresses are assigned to a devices by a router within the network.

Both the IPv4 and IPv6 specifications define private IP address ranges








Packet

It is a small segment of a larger message

It transfer data between networks. it has network address and logical address.           


Frames

It is the unit of data used in the link layer, which transfer data on a network. it has source and destination MAC address and physical address



Clints and Server

Client- server networks are computer networks that employ a dedicated computer to store data, manage/provide resources, and control user access(Server).

Server is also used in three ways such as

  • Server operating system
  • Server computer
  • Server software








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