Is the Internet Running Out of Addresses?

According to the Number Resource Organization that represents the five Regional Internet Registries, we are down to 10 percent cushion of the available IPv4 (Internet Protocol version 4) addresses.  These are the numerical addresses that are assigned to servers and web sites on the Internet.  My website,, for instance is at address

In IPv6 this would look like 2002:0:0:0:0:0:4ad0:52bf.

When I was in the telephone business, we went through this experience first with 800 numbers, which was solved by creating the 888, 877, and 866 toll free number prefixes.  Locally, we went through this in Minnesota, twice, first when St Paul was split off from the 612 area and into its own code 651, then again, when the metropolitan suburbs were split off into 763 and 952 area codes.

There is a solution to the problem of dwindling IPv4 addresses, that actually has been around for a while, but has just not been widely adopted, and that is the IPv6 addressing scheme.  The difference is monumental.  The current IPv4 system can realistically address about 4.3 billion machines.  Unfortunately, we are there.  IPv6, when fully implemented will be able to address 340,282,366,920,938,463,463,374,607,431,768,211,456 machines.  Not sure what that number even is, I got lost after 340 decillion, if that is really a number (million, billion, trillion, quadrillion, quintillion…..)  The TCP/IP Guide web site called it “over 300 trillion trillion trillion addresses.”  In any event, it should be enough for a very long time.

The problem is people like me – guys who know and are comfortable in the familiar 32 bit binary address space.  It is going to take a bit of learning to come to grips with addressing and networking in the newer 128 bit hexadecimal address space of IPv6.  For those of you who are normal, hexadecimal is base 16, and includes the digits 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, a, b, c, d, e, and f.   It’s tough to do base 16 calculations in your head. 

There are a couple of interesting articles on this subject that I have read.  One is from Tech Republic, and an older two-part series from the Internet Protocol Journal, The End of Eternity part one, and part two.  Not an easy read for the novice, but great for a deeper understanding of the problem, and the difficulties with mounting a solution.  For those in the profession who are looking for a free tutorial, there is The TCP/IP Guide web site.


About the Author:

I am a cybersecurity and IT instructor, cybersecurity analyst, pen-tester, trainer, and speaker. I am an owner of the WyzCo Group Inc. In addition to consulting on security products and services, I also conduct security audits, compliance audits, vulnerability assessments and penetration tests. I also teach Cybersecurity Awareness Training classes. I work as an information technology and cybersecurity instructor for several training and certification organizations. I have worked in corporate, military, government, and workforce development training environments I am a frequent speaker at professional conferences such as the Minnesota Bloggers Conference, Secure360 Security Conference in 2016, 2017, 2018, 2019, the (ISC)2 World Congress 2016, and the ISSA International Conference 2017, and many local community organizations, including Chambers of Commerce, SCORE, and several school districts. I have been blogging on cybersecurity since 2006 at

Add a Comment

This site uses Akismet to reduce spam. Learn how your comment data is processed.