NPCI

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The Network Protocol Control Information is the first part of a Network Protocol Data Unit.

The structure of the NPCI is variable and controlled by the NPCI Control Octet

NPDU
NPDU
NPCI Octets Meaning Notes
1 Version (Always 0x01)
1 NPCI Control Octet Establishes if NSDU is a Network Layer Message or APDU
2 DNET Only present if DNET, DADR, Hopcount present flag set in NPCI Control Octet
1 DLEN Only present if DNET, DADR, Hopcount present flag set in NPCI Control Octet
Variable DADR Only present if DNET, DADR, Hopcount present flag set in NPCI Control Octet
2 SNET Only present if SNET, SADR present flag set in NPCI Control Octet
1 SLEN Only present if SNET, SADR present flag set in NPCI Control Octet
Variable SADR Only present if SNET, SADR present flag set in NPCI Control Octet. Is the 4 byte IP address and port number in BACnet/IP. (6 bytes total)
1 Hop Count Only present if DNET, DADR, Hopcount present flag set in NPCI Control Octet
NSDU Variable, either an APDU or a Network Message


See the specification clause 6.2 Network Layer PDU Structure



Keyword List
APDU BBMD BVLC BVLL DADR DNET Encoding I-Am LSAP MAC NPCI NPDU NSAP NSDU SA SADR SNET

Device Profiles

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Glossary



Keyword List
APDU BBMD BVLC BVLL DADR DNET Encoding I-Am LSAP MAC NPCI NPDU NSAP NSDU SA SADR SNET

Device Profiles

Edit this box.

Glossary