# MicroNugget: How to to Select Subnet Sizes for VLANs

## The Most Common Subnets Used

* /22 (255.255.252.0) - 1024 IPs / 1022 usable
* /23 (255.255.254.0) - 512 IPs / 510 usable
* /24 (255.255.255.0) - 256 IPs / 254 usable
* /29 (255.255.255.248) - 8 IPs / 6 usable
* /30 (255.255.255.252) - 4 IPs /2 usable
    * point-to-point WAN uplinks

HSRP / VRRP - Virtual IP Address

VLANs Sample

* VLAN 1 = unused (none)
* VLAN 10 = server/printer (/24)
* VLAN 20 = VOIP (/24)
* VLAN 30 = guest (/22)
* VLAN 40 = internal (/22)
* VLAN 40 flex (/24)