An ITU standard which defines a method for how to encode 32k data on a 64k ISDN B-channel. Used for instance with the PIAFS wireless data protocol. The encoding works by setting the lowest nibble of a byte to F, making it insignificant to the receiver (whom must understand the data to be decoded using I.460). Consider the following example:

BF AD DF 3F 1F 3F 3F 7F DF 0F 0F DF

Would come out as:

BAD 31337 D00D

After being decoded as I.460 data.

However: please take note that if you implement an i.460 receiver the bottommost nibble of the byte does not indicate the sync position of the data! Things may be shifted from what you would expect. Take for example this simple example:

12 34
Encodes as:

1F 2F 3F 4F

It may also encode as:

2F 4F 6F 8F the topmost nibble may be shifted by n-positions (in this case 1 position). To illustrate futher:

0001 1111 (1F) may encode as 0010 1111 (2F) as the topmost nibble is shifted one to the left.

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