Back when the internet was created, IPv4 seemed sufficient. The 32-bit address space allows for 2^32 addresses, or 4,294,967,296 addresses. 4 billion is a large number, but in 2017, an estimated 8.4 billion devices were online. In 2020, experts estimated there would be 20.4 billion devices! (source: https://www.zdnet.com/article/iot-devices-will-outnumber-the-worlds-population-this-year-for-the-first-time/ (Links to an external site.) )

IPv6 tries to fix this problem, by providing 2^128 addresses. Remember, 2^33 would have doubled the number! IPv6 provides 340,282,366,920,938,463,463,374,607,431,768,211,456 possible addresses.

• How do you even say that number?? (Hint: I use wolfram alpha)
• IPv4 was created in 1980, making it just under 40 years old. How long do you think IPv6 will last before we run out of addresses?
• what new types of devices (that don't exist yet) will be online in the next 40 years?