Subject: digit map questions

From: "John A. Voelker" <[email-masked]>
Date: Wed, 17 Nov 1999 15:58:39 -0600

A colleague asked me to place on the list some questions he had concerning digit
maps (from  S7.1.13 of the h.248v12 draft):  Would appreciate any
clarifications.

John
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1. What is the correct operational model for the inter-digit timing
mechanism?
  - One timer for the entire digitmap whose timeout interval is changed
by an L or an S in the digitmap, or
  - Two timers that are reset following each digit and generate an "L"
or "S" when they expire?
The wording of rules 2 and 3 seems to imply the first, but then I'm
unclear on the use of "L" and "S" in the digitmap. Also, are there
situations where the conditions of both rules are true?
2. This question assumes the first of the models listed above.  If
several viable alternatives specify different inter-digit timeout
values, which one is used?  For example, a "4" is received when the
digitmap is:
    { [2-9]Lxxxxxx | [3-8]Sxxxxxx }
3. What does the "." character indicate?  It appears to perform the same
role as "*" in regular expressions, i.e. that it means 0 or more of the
immediately preceding digitPosition.
4. What are the semantic restrictions on syntactically correct
digitmaps?  For example, it doesn't seem valid to have more than one L
or S in an alternative.