Ip and mac address

#1

i understood that mac address is the address that different devices have and its unique. i want to know:

  1. Can ip address of different system be same?
  2. Does ip address changes time to time?
  3. Can we change ip address ? And mac address too?
#2

No, the IP address is unique to a system. Every node in a network must have an unique ip address. Your can search more on “IP conflict” on net.

Yes, there are two types of addressing: Static(Not changing, predefined) and Dynamic (assigned by router using DHCP)

IP address can be changed when using static IP address. For Mac address changing, it is called Mac spoofing. Read this https://www.howtogeek.com/192173/how-and-why-to-change-your-mac-address-on-windows-linux-and-mac/