RFC 1597 Summary

RFC 1597 provides for a group of Internet Networks that will never be assigned. Furthermore, these addresses will not route through the Internet. This makes them the proper choice for use in a corporate Enterprise Network.

A Large Address Space

The networks defined in RFC 1597 represent enough "room" to accommodate the needs of any corporation, no matter how large. This excerpt from RFC 1597 lists the address ranges reserved.
        10.0.0.0        -   10.255.255.255
        172.16.0.0      -   172.31.255.255
        192.168.0.0     -   192.168.255.255
The first range is an entire "Class A Network" consisting of 2-to-the-24th-power addresses or around 16 million hosts once the required broadcast addresses are reserved. This is a very large space.

The next range can be thought of in several different ways. It is either 16 "Class B Networks" each containing 65 thousand host addresses, or a single 20-bit address space containing one million addresses. It can actually be split up in more combinations, but in any case, this also represents a lot of room.

The last range is the equivalent of 256 "Class C Networks" each capable of nearly 256 hosts. Because they are contiguous, they may be treated as larger networks, up to the maximum of 65 thousand addresses.

What Does This Mean?

The bottom line with this RFC is that no corporation that is not an Internet Service Provider will ever again need its own registered IP Addresses. Conversely, no corporation that needs to build an IP-based Enterprise Network will ever again be limited by the size of the registered network that they have.

This is ground breaking news! Savvy Network Designers are rejoicing worldwide!

What If I Need to Connect to the Outside?

In the footsteps of RFC 1597 came RFC 1631, which defined the minimum functionality of a new device, the Network Address Translater. Network Safety Corporation is proud to be a premier supplier of devices that comply with RFC 1631 and bring even more tools for the Network Designer. Our NetNAT and DialNAT products demonstrate our commitment to the Internet community in general, and to the designers of Enterprise Networks in particular.

This page was last modified on 23 September, 1995.


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