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FLUTTER UUID GENERATOR MAC

So the uuid1() method is not useful in data-sensitive applications.

FLUTTER UUID GENERATOR MAC

The major drawback of the uuid1() method is that this way includes the use of the MAC address of the computer, and hence can compromise privacy, even though it provides uniqueness. The administered MAC addresses guaranteed to be globally unique if the getnode() function fails to get the MAC address it returns the random 48-bit number with a multicast bit as recommended in the RFC 4122. If a machine has more than one network universally administered, then the MAC addresses are returned instead of over locally administered MAC addresses. The uuid.getnode() method is used to get the MAC address of the network interface. We can apply the node and clock sequence to function explicitly. Generate unique ID for Host using node and clock sequence Now, we can use this id anywhere in our application or use in cryptography to further strengthen the encryption. You can see that we have generated the random id. Print("The random id using uuid1() is : ") Otherwise, a random 14-bit sequence number is chosen.

If clock_seq is given, it used as the sequence number.

If a node not given, then the uuid.getnode() function is used to obtain the Universally administered MAC addresses of a current host.

The node is the hardware address, which is the 48-bit positive integer.

The node and clock_seq are optional arguments.Syntax uuid.uuid1(node=None, clock_seq=None) Parameters Python UUID module provides uuid1() method that generates the random id using the MAC address and time component. UUID.SafeUUID : SafeUUID.unknown Generate Random IDs using UUID.uuid1() Print('UUID.clock_seq : ', UUID.clock_seq) Print('UUID.clock_seq_low : ', UUID.clock_seq_low) Print('UUID.clock_seq_hi_variant: ', UUID.clock_seq_hi_variant) Print('UUID.time_hi_version : ', UUID.time_hi_version) Let’s extract and print the above information for uuid.uuid1().

clock_seq_hi_variant : Next 8 bits of id.

time_hi_version: The next 16 bits of id.

variant: It is a variant determining the internal layout of UUID.

version: It is the version number of UUID.

hex: Returns the random id as 32 character hexadecimal string.

int: Returns id in the form of a 128-bit integer.

bytes: Returns id in the form of 16-byte string.

UUID4 uses the pseudo-random number generators to generate UUID.

The UUID 3 uses MD5 hashing, and UUID 5 uses the SHA-1 hashing.

UUID3 and UUID5 use cryptographic hashing and application-provided text strings to generate UUID.

The uuid1 version uses the IEEE 802 MAC addresses.

UUID1 generates UUID using a Host MAC address, serial(sequence) number, and the current time.

Python UUID module provides the following versions of UUIDs. UUID generated using the uuid module is immutable. And the total number of ways to generate r UUIDs is n^r since each of the r UUIDs has n different possibilities.Hence using the Python UUID module, you can generate versions 1, 3, 4, and 5 UUIDs. The first UUID can be any of n possibilities, the second can be any of the n except the first ( n-1), the third can be any except for the first two ( n-2), and so on. The number of ways to have no duplicates is n * ( n-1) * ( n-2) * …( n-( r-1)). if r > n, then there must be some duplicates. Right away, we know that if the number of UUIDs generated exceeds the space of possible UUIDs, i.e. In the version 4, variant 1 type of UUID, 6 bits are fixed and the remaining 122 bits are randomly generated, for a total of 2¹²² possible UUIDs.

32 hexadecimals x log2(16) bits/hexadecimal = 128 bits in a UUID. Each character can be a digit 0 through 9, or letter a through f. The 32 characters of a UUID are hexadecimals, or base-16 representation. Let’s calculate the probability, p, that there are no duplicates among a set of r UUIDs. If UUIDs are generated randomly, then there must be some chance that a sequence is generated more than once, especially as we generate more and more. Each one is unique across space and time. There are several ways to generate them, including methods based on time, MAC addresses, hashes, and random numbers, but they make the same promise: no two are identical. UUIDs are handy for giving entities their own special names, for example, in a database. It looks like a 32-character sequence of letters and numbers separated by dashes. UUID stands for universally unique identifier.