ITPEC FE Morning April 2022 Question 34

Broadcast Address Calculation — find the broadcast address from CIDR notation.

Given 192.168.128.0/26:

• •Prefix length = 26 → host bits = 32 - 26 = 6
• •Block size = 2^6 = 64
• •Broadcast = 0 + 64 - 1 = 63
• •Result = 192.168.128.63

Why not others:
- (b) 192.168.128.127 — broadcast for /25 (block size 128)
- (c) 192.168.128.252 — not a valid broadcast for any standard subnet
- (d) 192.168.128.255 — broadcast for /24 (block size 256)

Key rule: Broadcast = network address + 2^(32 − prefix) − 1. All host bits set to 1.

AI-generated — may contain errors