Practical_modern_SCADA_protocols_-_dnp3,_60870-5_and_Related_Systems

532 Index
distributed network protocol (DNP3) (Continued)
fundamental concepts:
enhance performance architecture, 76–7
functions of model layers, 77–8
OSI 7 layer model, 73–6
implementation rules/recommendations, 154
16- and 32-bit variations, 158
actions on slave device startup, 155
confirmation and retries, 157
counter roll-over, 158
data classes/events, 155
default variation, 155
error responses, 154
flags in objects, 158
fragments and frames, 156–7
freeze operations, 159
multiple objects, 157
operating binary outputs, 156
order of responses, 155
over-range analog objects, 158
time synchronization, 159
time-tagged binary input events, 159
unsolicited responses, 156
interoperability between devices, 153
confirming, 153–4
profile document, 153
interoperability/open standard, 67–8
key to data structure, 140–2
message transaction flow diagrams, 104
collision with unsolicited response, 108
confirmation timeouts, 106
effects of network delays, 107–8
multi-fragment response, 105
rules for unsolicited message transactions,
108–11
typical transaction, 105
object header, 118–19
field, 119–20
variation zero, 120
physical layer, 80–1
description, 81
full-duplex procedures, 83
half-duplex procedures, 82
procedures, 81–2
services provided, 81
topologies, 81
polling/communications options, 162–3
qualifier codes, 121–2
all-object mode, 125
index-size sub-field, 122–3
non-ranged mode, 125–7
object identifier mode, 127–8
point indexes, 128
range-absolute mode, 124
range-index mode, 123–4
reasons for using, 72
sub-set definitions:
function code quick reference, 147
implementation levels, 143–4
implementation table, 147–52
implementation tables, 144
qualified field, 146–7
qualified field quick reference, 146
summary of implementation, 144–6
system topology, 70–1
TCP/IP and UDP/IP:
carrying over a network, 168–9
general considerations, 164–6
Internet protocol suite, 166–7
link layer confirmations, 169
time synchronization, 169
time synchronization:
general method, 163–4
global, 164
transmission procedures:
confirmed send user data, 92–3
CRC error code, 96–8
main points, 90–1
request link status, 94–6
reset user process, 91–2
test, 92
unconfirmed send user data, 93–4
transport layer (pseudo-transport):
data unit, 98–9
description, 98
transport header, 99–100
understanding message structure, 78
application layer, 79
buildup, 78–9, 80
data link layer, 80
physical layer, 80
pseudo-transport layer, 80
water industry application, 374–90
DNP3/IEC 60870-5 comparison:
addressing, 308
application functions/data objects, 308–9
choice/winner, 311
complexity, 309–10
data link communications, 308
differences, 308
efficiency, 310
frame format, 308
general similarities, 307
interoperability, 309
security, 309
summary, 310