I have recently posted about my predictions for the Cloud over the next three to five years, how the Cloud can significantly improve public education, and about your coming Smart House. But there is a problem: we are literally running out of room in the Internet, a key component to Cloud Computing.
OK, we are not really running out of storage space, but we are running out of addresses. Like the Island of Manhattan, there are no more available street addresses – to hold more people and businesses you have to grow vertically, putting more stuff at the same postal address. Every node on the Internet is assigned a numeric Internet Protocol (IP) address. When you type in a web page name, called a uniform resource locator (URL), that name is translated to an IP address. Since 1981, the most widely used format of an IP address, called IPv4, is represented as a series of four numbers, each between 1 and 255 separated by periods. For those of you who care, this is equivalent to a 32-bit address in a computer. For example, my website URL “wrlapinsky.com” maps to IP address 188.8.131.52. In theory, there are almost 4.3 billion such addresses, however large blocks are reserved for special uses. Almost 300 million addresses are reserved for private networks and multicast addresses.
This IP address space is managed by the Internet Assigned Numbers Authority (IANA) globally and by five regional Internet registries (RIR). IANA ran out of numbers in January 2011. The Asia Pacific RIR ran out of numbers in April 2011. The remaining RIRs are projected to run out in a few years.
In 1990 only a small fraction of the hundreds of millions of households in the developed world had a high-speed Internet connection. By 2005, almost half did. As early as the mid-1990s, it was clear to some that IPv4 did not have enough addresses to support the projected growth.
Many companies started using a trick called NAT to essentially allow multiple organizations to re-use the same set of IP addresses. NAT (network address translation) allows, for example, a large company to have a single IP address that is visible to the outside world, but behind that single IP address to have a potentially large set of local IP addresses that are individually invisible to the outside world. This is like a company having a single phone number through which multiple external callers can reach multiple internal people through different extensions.
Another trick is to reuse IP addresses through Dynamic Host Configuration Protocol (DHCP). DHCP allows a device to ask for an IP address when it logs on, so a relative small set of IP numbers can support a much larger number of real devices, as long as the number of logged on devices does not exceed the number of available IP addresses. If you have a high speed Internet connection from Comcast, Verizon, or one of the hundreds of other ISPs (Internet Service Providers), they allow you to have a relatively small number of devices connected at the same time – for us it is six. We have more than six devices that could be connected to the Internet, but so far that restriction has not been a problem for us.
Other schemes involve having a multitude of “web sites” behind a single sometimes invisible web site. For example, WordPress hosts millions of blogs, including this one, using just a handful of IP addresses.
These schemes work for physically static places like office buildings and homes, although it does add a significant amount of administrative work to mange it and make it invisible to users. They do not work very well for moving devices like laptops, tablets, smart phones, and cars. This is especially true when those devices are physically moving more than a few hundred feet in the same connection session.
The solution is a new Internet protocol called IPv6.
Yes, there was an IPv5 but that designation was given to a special protocol created to support transmission of voice, video, and distributed simulation with a totally different philosophy about what a “connection” really was. In the IPv5 case, a connection had a relatively long life. In the IPv4 and IPv6 case, connections have a fairly short life, sometimes just a request and response.
You may remember that IPv4 is a 32-bit address. IPv6 is a 128-bit address, notated as eight groups of four hexadecimal digits separated by colons. For example, 2001:0db8:85a3:0042:0000:8a2e:0370:7334.
Hexadecimal is a base-sixteen numbering system. In the same way that binary uses only 0s and 1s to represent any number and decimal uses the ten digits 0 through 9 to represent any number, hexadecimal uses the ten digits plus “a” for 10, “b” for 11, “c” for 12, “d” for 13, “e” for 14 and “f” for 15. Just like the binary number 101 is 1 x 22 + 0 x 2 + 1 = 5, and the decimal number 234 is 2 x 102 + 2 x 10 + 4 = 234, the hexadecimal number 1c8 is 1 x 162 + 12 * 16 + 8 = 456.
The result is that IPv6 can support more than 3 followed by 38 zeros addresses, or enough addresses for every person on the planet to have 4 followed by 28 zeros devices. To put the number of devices per person in some perspective, it is about 6 billion times the number of grains of sand on all the beaches of the earth, at least according to one estimate. So the implementation of IPv6 should provide the address space for all of those Cloud-connected devices in your Smart House, car, school and workplace for the foreseeable future.
However, adoption of IPv6 has been very slow. By 2011, only about one quarter of computers were even IPv6 capable, and less than one percent of the top million websites were IPv6 accessible. Fortunately, the IANA exhaustion event is spurring increased adoption.
Fortunately, IPv4 and IPv6 messages can coexist through tunneling techniques that are invisible to most users. In fact for almost everybody, the transition will be invisible.
The last word:
Is your company or organization moving forward or in the way? Does you web site support IPv6? Is there a plan to get your servers and workstations upgraded to support IPv6? Does you network support organization have a plan to transition to IPv6?
If you want to participate in the coming explosion of devices in the Cloud, you need to be ready.
Keep your sense of humor.