CIDR Prefix: /16
CIDR Prefix Reference Guide
A Class B default subnet mask block. Providing 65,536 addresses, it is highly popular for cloud VPC design backbones and large corporate WAN networks.
255.255.0.0
0.0.255.255
65,534
65,536
11111111.11111111.00000000.00000000
Class B Default
How to use this CIDR reference
1. Match Routing Limits: Check netmask binary allocations to determine subnet partition boundaries.
2. Size Host Tiers: Evaluate the usable hosts metrics to verify if the block matches host requirements.
3. Firewall Mapping: Use the wildcard mask values to write access control rules (ACLs) in networking equipment.
Understanding Prefix Networking Size
CIDR (Classless Inter-Domain Routing) prefixes represent the allocation size of subnetworks. The numeric prefix (/16) specifies the number of active routing identifier bits. The remaining host bits address connecting endpoints. Netmask and wildcard values are standard mappings required to write network forwarding tables, routing policies, and local system firewalls.