Version 4 UUID
What is a Universal Unique Identifier (UUID)? A universal unique identifier or, more commonly known as a UUID, is a 128-bit number that are assigned to each object for purposes of identifying them.
A common use case for this information is creating virtual private networks (VPNs) so you do not have to worry about users being able to identify which device belongs to what account because they do not know the internal IP address.
Another example would be computer files; most operating systems require you to include a unique identifier with every file so you can easily track down who owns it and copyright laws are enforced.
Malgo's UUID generator tool is a great resource online that allows you to create as many UUID's as you need.
History of UUIDs
Originally, Universally Unique Identifiers were referred to as MAC (Message Authentication Code) addresses or Message Authentication Codes. They are very famous now due to their use in encryption!
In 1997, University of California, Irvine researchers Daniel J. Weise, Prakash Narayanancutur, and Rob Virding coined the term “Universally unique identifier” or “UUID” for these numbers.
We can learn some important things about this new type of GUID from looking back at its history.
The first few years was spent figuring out how to create good random identifiers
It took several iterations before people could agree that 128 bits was enough length for an excellent UUID.
Now we have version 1 through version 3 of the UUID format!
Version 4 is the most recent update to the standard. It changes how the algorithm works to produce more entropy than past versions. This makes it harder to predict future UUIDs because there are more possible outcomes.
What are UUIDs?
Universal Unique Identifiers (or, even more simply, universal identifiers) are a way to identify objects. Technology uses this system all the time to assign unique identifiers for different types of items or users.
The term “uuid” is short for universally-unique identifier. Technically speaking, it is not an actual string of characters, but rather a complex formula that creates a very long string of numbers.
This method of identification was invented in 1997 by Jeffrey Gillette as part of his Ph.D research at Tufts University. Since then, it has become one of the most popular ways to create unique, cryptic identifiers.
Many technology companies now use the same format for their own internal IDs. Some use them for user accounts, others for computer hardware, and some for software too!
Why do we need new IDS?
There are several reasons why tech companies start looking into creating their own unique IDs. One of the biggest is security.
By having separate IDs, you can have different levels of access depending on what position someone holds within your company. This helps protect people from each other, and protects your business from fake employees or outsiders trying to gain access to important information.
Security also comes down to how hard it is to find these IDs. Because they are completely random, there are no pattern or sequence to look out for when searching for them.
Examples of UUIDs
Many computer programs require unique identifiers to work effectively. These include applications you use typically every day, like email clients, web browsers, and operating systems.
Software makes copies of these apps so they do not have a unique identifier that only one app has. If two different software packages share the same ID, your messages may get mixed up!
A universal unique identifier (UUID) is a good way to avoid this problem. A UUID is a long string of numbers and letters that are very difficult to predict. No matter how hard you try, it will always be a surprise!
There are many ways to create a UUID. Some use fancy math formulas, some just shuffle around bits of data, and others take help from an outside source. Here we will go over version 4 Unicode UUIDs, also known as V4 UUIDs.
Converting a UUID to hex
There are two ways to get the fully-formatted version of a UUID. The first is by using the -u option with the uuidtool program. This will give you the long form, which we discussed earlier.
The second way to obtain the formatted string is via the special value called ‘short’ or ‘hex format’. This was introduced in Mac OS X El Capitan and can be used as an alternative if you no longer have access to use the long form.
To create this short form, all you need to do is add the number 0 to the end of each part of the original UUID. These parts include the vendor (XX), product (YY), and variant (ZZ) fields.
This means that instead of getting 12345678-1234-567-89AB-CDEF012344556 you would get 2369c788-09ac-edb8-6543-a5026068686.
Converting a UUID to bytes
The two main components of a universal unique identifier are the namespace and the UUID itself. The Universal Naming Convention (or UNO) for a UUID is an eight-byte string where the first four bytes are a time value, a hash of the namespace, and then four more bits that are set either one or zero.
The last byte is typically left as 0’s but some variants use bit ones which we will go over later. There are several ways to convert a longer UUID into its component parts. This article will focus on converting from what are known as version 1 through 4 UUIDs to their respective components.
Version 1 UUID
A version one uuid consists of 122 random numbers separated by dashes in a base 16 number system. Each group of three numbers gets converted into hexadecimal representation using padding if necessary.