Network: 21.0.0.4/31
Addresses: 2 (2¹)
First IP: 21.0.0.4 (4.0.0.21.in-addr.arpa)
Last IP: 21.0.0.5 (5.0.0.21.in-addr.arpa)

/8 Operated By: DDN-RVN

• 21.0.0.0/8
• 20.0.0.0/8
• 22.0.0.0/8
• 21.0.0.4/30
• 21.0.0.4/32
• 21.0.0.5/32

• 0.0.0.0/0
• 1.0.0.0/8
• 127.0.0.1
• 30.0.0.0/8
• 192.168.0.0/16