0.0.0.0/1
PublicClass A — /1 prefix — 2,147,483,646 usable hosts
Network address — the base address of the block (0.0.0.0). All devices in this subnet share this prefix. Cannot be assigned to a host.
Broadcast address — packets sent to 127.255.255.255 are delivered to every device in the subnet. Also reserved — not assignable.
Usable hosts — the 2,147,483,646 addresses between those two that you can assign to servers, VMs, or interfaces.
Subnet mask — 128.0.0.0 is the dotted-decimal equivalent of /1. Older tools and Cisco configs use this format instead of CIDR slash notation.
Full Details
| CIDR Notation | 0.0.0.0/1 |
| Network Address | 0.0.0.0 |
| Broadcast Address | 127.255.255.255 |
| Subnet Mask | 128.0.0.0 |
| Wildcard Mask | 127.255.255.255 |
| Prefix Length | /1 |
| IP Address Class | Class A |
| Total IP Addresses | 2,147,483,648 |
| Usable Host Addresses | 2,147,483,646 |
| First Usable IP | 0.0.0.1 |
| Last Usable IP | 127.255.255.254 |
| Network (Hex) | 0x00000000 |
| Broadcast (Hex) | 0x7FFFFFFF |
| Address Type | Public / Globally Routable |
Binary Representation
The first 1 bits (1s in the mask) identify the network. The remaining 31 bits identify hosts within the network.
Subnet Breakdown — splitting into /2
This /1 block can be divided into 2 /2 subnets.
| CIDR | Network | Broadcast | First Usable | Last Usable | Hosts |
|---|---|---|---|---|---|
| 0.0.0.0/2 | 0.0.0.0 | 63.255.255.255 | 0.0.0.1 | 63.255.255.254 | 1,073,741,822 |
| 64.0.0.0/2 | 64.0.0.0 | 127.255.255.255 | 64.0.0.1 | 127.255.255.254 | 1,073,741,822 |