Aclara SGM1400 Series, Руководство пользователя

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58
S G M 1 4 0 0 S e r i e s S m a r t M e t e r U s e r M a n u a l – S M E T S 2
Prepayment Solution
Top-Ups
Credit top-ups are applied to a consumer account using a unique transaction
number (UTRN), sometimes referred to as a ‘token.’
UTRN (Token) Overview
The UTRN is constructed from the 19-digit Prepayment Token Decimal (PPTD)
appended with a further Check Digit, resulting in a 20-digit UTRN.
Prepayment Token Decimal (PPTD)
The Prepayment Token Decimal (PPTD) is a 19-digit decimal integer.
The most significant two digits of the PPTD are between 73 and 96, this being the
result of the addition of 7,394,156,990,786,306,048 (the K-Class 5 Offset) to the
decimal representation of the binary Prepayment Top-up Token (PTUT) to
distinguish it from other standard transfer specification (STS) defined tokens.
Prepayment Top-up Token (PTUT)
In binary form, the PTUT is an unsigned 64-bit integer (8 octets), constructed as
shown in the table below.
Class 5 Token
This format does not overlap with the framework provided by the existing STS
specification and indeed is a new domain of operation outside that of STS token
classes 0, 1, 2, and 3.
PTUT Format - Bit Assignments
PTUT Component Value Bits Note
PTUT Lead 0b000 63–61 Fixed value
PTUT Sub Class 0b0000 60–57 Fixed value
PTUT Truncated
Originator Counter
Bits 41-32 of the Originator
Counter
56–47 Used for anti-replay purposes
PTUT Value Class
0b00 if PTUT Value is to be
interpreted as multiples of 1/100
of currency unit
OR
0b01 if PTUT Value is to be
interpreted as multiples of
currency unit
46–45
If currency unit is set to GB pounds on
the ESME or GSME:
0b00 means PTUT Value will be
interpreted as GB pennies;
0b01 means PTUT Value will be
interpreted as GB pounds.
PTUT Value
The quantum of the PTUT
expressed as an unsigned binary
number of 13 bits in length, so
with leading binary zeros where
required
44–32
Thus, the maximum value is either:
£81.91 if PTUT Value Class = 0b00;
OR
£8,191.00 if PTUT Value Class = 0b01.
PTUT Supplier
MAC
See next slide 31–0