3.4 Network hardware
What is a NIC?
- a component that enables a computer to connect to a network
- it is assigned a MAC address at the point of manufacture
What is a router
- A device that forwards packets to their correct destinations in a network
What is the role of a router
- Receives packets from devices
- Finds the destination of packets using the IP address
- Forwards packets to the correct destination
- Assign private IP addresses to devices on LAN
- Finds the most efficient path to destination
- Maintains a table of MAC and IP addresses
- Can connect a LAN to an external network eg. internet
- Provides the LAN with a public IP address
MAC Address
- made up of 48 bits
- shown as 6 groups of two hexadecimal digits
- First half represents Manufacturer
- Second half represents Serial number
- Uniquely identifies a device on the network
- eg. 11:11:11:11:11:11
- MEDIA ACCESS CONTROL (only use if not referred by the question!)
IP Address
- consists of values between 0–255 / 0–FFF
- values are separated by full stops / colons
- it is a unique address
- can be static or dynamic
- can be public or private
- can be IPv4 / have four groups of digits
- can be IPv6 / have eight groups of digits
- in IPv6 :: can replace groups of zeros.
Static IP
- When a computer disconnects and rejoins a network
- ... the address does not change
- Address is assigned by the server/ISP
- A static public IP address is used primarily for hosting web pages or services on the internet.
Dynamic IP
- Each time the computer rejoins a network
- ... the address changes
- address is assigned by the network OS
- A dynamic public IP address is chosen from a pool of available addresses