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280 AUTOMATED FINGERPRINT IDENTIFICATION SYSTEMS
APPENDIX C—EFTS
ISSUES DOCUMENTED IN JULY 1997
Existing Scope of EFTS:
1. SRT “No Hit” Condition: There is no specification in the FBI-EFTS docu-
ment on how to return a No-Hit message in response to a Tenprint Image
Search (TPIS). Does one merely include the words “No Hit” in the 2.064
field (the mandatory field normally containing the candidate list)? In our
testing, we had pre-sent cards to all vendors, so that a No Hit condition
would not occur. Resolution: Still pending.
2. DAI Size Discrepancy: The EFTS lists contradictory size specifications
of the Destination Agency Identifier (DAI) and Originating Agency Iden-
tifier (ORI) found in Type-1 records. In the ANSI-NIST standard and the
EFTS, it says, “The size and data content of this field shall be defined by
the user and be in accordance with the receiving agency.” However, the
EFTS goes on to say, “This field shall be a ten-byte [or nine-byte respec-
tively] alphanumeric field.” So if this in fact is true, and since the DAI is
merely the other person’s ORI, what constitutes the extra byte? Resolution:
Still pending.
3. ORI/DAI Size Conflict with ANSI-NIST: The EFTS specifies a size for the
ORI and DAI, but the ANSI-NIST standard says that “the size and data
content of this field shall be defined by the user and be in accordance with
the receiving agency.” Which is correct? Resolution: Still pending.
4. Candidate Scores: Do we need another field in Type-2 Record for scores of
candidates? Currently, scores are not returned with the candidates. Reso-
lution: Still pending.
5. Score Meaning: Currently, all vendors have different methods and values
for scoring, e.g., a score of 1,000 with Vendor A may not have the same sig-
nificance as with Vendor B. Also, a score of 1,000 is not necessarily “twice
as good” as a score of 500. We need to further explore possible uniformity
and understanding of the scoring process. NOTE: This point is of interest
only if it’s decided to return the scores with the candidate lists. Resolution:
Still pending.
6. NTR Update: Nominal Transmitting Resolution (NTR) needs to be
updated. The Native Scanning Resolution (NSR) has a minimum value
defined, but there is no upward limit. On the other hand, the NTR is
limited to a maximum value of 20.47 pixels per millimeter (p/mm)
plus/minus .20p/mm (520 pixels per inch (p/in) plus/minus 5p/in) for
high resolution grayscale images, e.g., Type-4 records. The typical tenprint
scanner scans at 600p/in. Therefore, we are unable to take advantage of