I forwarded the question to the internet-history mailing list and Craig Partridge, chief scientist at BBN, said: Here's the relevant text from the RFC: 1. Private Address Space Sign up or log in Sign up using Google.
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Podcast Do polyglots have an edge when it comes to mastering programming Featured on Meta. Now live: A fully responsive profile. Related Hot Network Questions. Question feed. Server Fault works best with JavaScript enabled. The fact that there will be more than 24 billion internet-connected devices installed around the world by would be a huge surprise to the people behind Internet Protocol version 4 IPv4 , which is bits in size and contains 4,,, IPv4 addresses.
To address the shortage of IPv4 addresses, a method of remapping one IP address space into another was proposed. Network address translation NAT makes it possible to use a single public IP address for an entire private network. The Internet Engineering Task Force IETF , an open standards organization, which develops and promotes voluntary internet standards, dedicated several IPv4 ranges for private networks: bit block As you can see, the In most cases, this IP address is used by home broadband routers as their default address.
Yes, even routers have an IP address, called router IP address. In fact, routers that double as modems often have two IP address: one public and one private. The public IP address can be reached from the internet, while the private IP address is accessible only to devices that are connected to the same local network as the router. This IP address is not unique, any multiple routers can share it without any issues.
As you can see, the A router with a public IP address sends and receives data to and from the internet. The router then uses a private IP address for communication with devices in the local network, which are also assigned private IP addresses. Private IP addresses have become especially important with the emergence of the Internet of Things. When you use a network analyzer such as NetSpot visualize, manage, troubleshoot, audit, plan, and deploy wireless networks, you can expect to see anywhere from a few to several dozen wireless networks.
In reality, each network you find likely contains many different internet-connected devices that all share the same public IP address. All public IP addresses are completely unique. That means that each public IP address is directly assigned to just one device. With private IP addresses, things are slightly different. Because there can be an infinite number of private networks, there can also be an infinite number of devices with the same private IP address.
For example:. According to RFC If a suitable subnetting scheme can be designed and is supported by the equipment concerned, it is advisable to use the bit block class A network of private address space and make an addressing plan with a good growth path. If subnetting is a problem, the bit block class C networks , or the bit block class B networks of private address space can be used.
I'm not sure exactly what kind of "problems" with subnetting the authors were thinking of. Perhaps some pre-CIDR hardware didn't support Class A networks due to memory constraints though you would think it's the number of hosts, not the number of potential hosts, that matters.
This may have been useful for large organisations that wanted to run private subnets on pre-CIDR hardware. Please use I used to think that answering historical questions was a good idea, but I would like to avoid doing this on a regular basis, due to bad help vampire experiences. It doesn't seem necessary in this case. Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group.
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