Encoded / Decoded
Initially I was confused on how the card was encoded. What I misunderstood at first was that the terminology encoded does not mean encrypted. Encryption is something completely different, such as applying a key to scramble and unscramble information, whereas with encoding, a piece of an encoded string is easily converted to something legible, let me explain:
The binary string, 011010101111010100001110101110, is 448611246in decimal format. Now, if you take a piece of that binary string, say bit 10 to bit 19 (or 1101010000), and convert to decimal format, you would get 848. The number 448611246 could mean absolutely nothing, whereas 848 could be a relevant number, such as the badge number.
The bits from a (0-9): 427
The bits from b (10-19): 848
The bits from c (20-29): 942
Review the first link from hidcorp.com to get a better understanding.
Xerox Proximity Card Reader
Xerox has a fairly new product that allows one to use current facility HID cards as an authentication method for scanning to email, et cetera. As stated above, HID cards when scanned will produce a binary number, which will contain encoded information typically pertaining to card # (badge #), facility #, et cetera.
The card reader, by Equitrax, integrates with the Xerox Secure Access application allowing users to authenticate for scan to email with a HID badge. The Xerox Secure Access application is the middleware between the Equitrax card reader and your specific directory service, such as Active Directory or eDirectory.
Card Reader Problem, HID Card Reads as Base 8
Unfortunately, the Xerox card reader or the Xerox Secure Access software produces a base 8 representation of the HID binary number.
Using the HID decoding as specified in your card access system or as specified by HID will not work correctly as the offsets now relate to a base 8 versus a base 2 (binary) number, effectively shortening the number length. The binary number, 011010101111010100001110101110, is 3257241656 in base8, going from 30 digits to 10 digits.
Currently, the only resolution I have found for this problem is use the full base8 output of the HID card and associate that number with the specific network user account.
Understanding Card Data Formats: http://www.hidcorp.com/pdfs/undrstndg_card_data_formats.pdf
Format and Facility (Site) Code explained: http://www.identisource.net/format_and_facility_codes_expl.cfm
The Standard 26 bit Format: http://www.identisource.net/26_bit_format_layout.cfm