subnet mask

## Subnet Mask

Its dividing Network_OSI into smaller inner networks In decimals is the sereies of ones and zeros at the end(111111.11111.11111.0000) #alt-name /24 Classes Interdoamin Routing (CIDR)(‘slach notation’) In order to calculate this we sum up all the ones use cheat sheet >[!example]- >CIDRCalculation_visual.png >>[!tip]- Cheat sheet >> CheatSheetCIDR_visual.png

  • Each subnet is identified by a unique network address and a subnet mask, which is used to determine the range of IP addresses that belong to that subnet.
    • e.g.,255.255.255.0
      • Used by the local device in conjunction with IP to determnie what subnet its on
        • The subnet mask is not (ussualy transmited across the network)

Now we use VLSM instead of subnet classes

subnet construction >[!quote] defult gateway DHCP server