Page tree
Skip to end of metadata
Go to start of metadata

What's up with ODA (offline data authentication) in the US Market?

Can I turn off ODA (SDA,DDA, or CDA) support for an Augusta?



Introduction:

CAPKs are used by the terminal to perform security related matters with the card. More specifically they are used to perform ODA (offline data authentication). So, the question has been posed... "Do I need to load CAPKs for a device deployed in the US (online only market)?" The answer depends on the terminal settings and processor requirements. If the terminal settings define the ODA (SDA, DDA or CDA) as supported (as is the case for ID TECH's Augusta and AugustaS products), and the processor requires successful ODA (when supported) to approve transactions, then yes, you WILL need to load CAPKs.

Some Facts:

  • Augusta supports ODA always. It cannot be turned off with the currently available Terminal Settings (link: Which Terminal Settings Am I Allowed to Change?)

  • Tag 95 has four bits relative to the subject (link:  What does TVR mean?)

    • Byte 1: 
      0------- Offline data authentication was not performed
      -0------ SDA failed
      --0----- ICC data missing
      ---0---- Card appears on terminal exception file
      ----0--- DDA failed
      -----0-- CDA failed
      ------0- SDA selected
      -------0 RFU
  • If either the card or the terminal do not support ODA, then Byte 1 bit 8 of tag 95 will be set (Offline data authentication was not performed). 
    • Note: Augusta supports ODA and most cards support ODA. But, some do not 
  • If the terminal and the card both support ODA then ODA will be attempted. If no CAPKs exist the it will fail. The result will be that either bit 7, bit 4 or bit 3 will be set.

Terminal Verification Results (Tag 95), byte 1, has results for Offline Data Authentication:

Bit 8:  Offline data authentication not performed
This is triggered to "1" if:
The Application Interchange Profile (tag 82), Byte 1, supported authentication methods does NOT HAVE A MATCHING SUPPORTED authentication method in Terminal Capabilities (Tag 9F33), byte 3.

If there is a MATCHING DATA AUTHENTICATION METHOD in ICC AIP Tag 82 and Terminal capabilities 9F33, then Offline Data Authentication WILL be performed, and Bit 8 of TVR (byte 1) will "0"

Bit 7:   Offline  static data authentication Failed
If both AIP (tag 82) byte 1, bit 8 and Term Cap. (tag 9F33) byte 3 bit8 support SDA, but the CAPK is not found on the terminal, or the CAPK found but invalid, SDA will FAIL and this bit will be "1".  The terminal decides which CAPK to use by the AID name (example A000000003) and the CAPK index (tag 8F) from the ICC.

Bit 4:   Offline  dynamic data authentication Failed
If both AIP (tag 82) byte 1, bit 7 and Term Cap. (tag 9F33) byte 3 bit7 support DDA, but the CAPK is not found on the terminal, or the CAPK found but invalid, or the dynamic data is incomplete or could not be collected, DDA will FAIL and this bit will be "1".  The terminal decides which CAPK to use by the AID name (example A000000003) and the CAPK index (tag 8F) from the ICC.

Bit 3:   Combined DDA/AC Generation Failed
If both AIP (tag 82) byte 1, bit 1 and Term Cap. (tag 9F33) byte 3 bit4 support CDA, but the CAPK is not found on the terminal, or the CAPK found but invalid, or the dynamic data is incomplete or could not be collected, or the AC could not be generated, CDA will FAIL and this bit will be "1".  The terminal decides which CAPK to use by the AID name (example A000000003) and the CAPK index (tag 8F) from the ICC.