Network segment
A portion of the machine network provides a local communication domain for connected control functions.
ISO 11783 FOUNDATION / PART 04
Network
layer
Part 4 addresses communication when ISO 11783 control functions are separated by network segments and an interconnection function must carry information between them.
01 / Identity & role
One machine can contain
more than one network segment.
ISO 11783-4:2011 is titled Network layer. The referenced publication is the second edition, issued in 2011.
Its role is to define the services needed when communicating control functions are not on the same immediate segment and network interconnection functions sit between them.
02 / The problem it solves
A larger machine network needs
controlled paths between segments.
Segmenting a network can separate traffic, physical areas, or machine domains, but it creates a new question: how does communication reach a control function beyond the local segment?
Part 4 provides a common architectural answer so interconnection devices can move appropriate communication without making higher-level applications understand every physical path.
03 / Position in the stack
Network reach sits above
local data transfer.
Part 4 builds on the physical and transfer foundation. It supports higher functions by extending communication context across defined network boundaries.
Application servicesMachine functions consume information without managing every segment path
Network layer · Part 4Interconnection functions support communication between network segments
Data link and transport · Part 3Information is framed and transferred on a segment
Physical layer · Part 2Each segment has a physical communication medium
04 / Key concepts
Segments, interconnection,
forwarding, and containment.
Interconnection function
A dedicated function links segments and decides how relevant communication crosses the boundary.
Cross-segment reach
Communication may need additional context and handling when source and destination are not local.
Traffic boundary
Interconnection can preserve necessary communication while avoiding an assumption that every frame belongs everywhere.
05 / Who implements it
Gateway responsibility belongs
to system architecture teams.
RoleDirect responsibilityKey question
Tractor OEMDesign and integrate segmented machine networksWhich control functions and traffic must cross each boundary?
Implement makerUnderstand whether required functions are local or reached through a tractor gatewayDoes the product rely on transparent cross-segment communication?
Terminal developerOperate correctly when working sets or services sit beyond a segment boundaryHow are discovery, transfer, and failure handled across the path?
FMIS developerUsually no direct gateway implementationWhich machine-side path must succeed before task data appears?
06 / Interactions
Part 4 connects local transfer
to identified participants.
LOCAL / P02-P03Segment communicationPhysical and data transfer work locally
BRIDGE / P04Network interconnectionDefined functions link network segments
JOIN / P05Managed participantsControl functions establish usable identity
SERVE / P06-P14Application featuresHigher services communicate across the architecture
07 / Boundaries
A network diagram does not
define gateway behavior.
This page is not ISO 11783-4.Use the licensed official publication for interconnection unit types, protocol behavior, requirements, and engineering decisions.
No routing or forwarding tables are reproduced.FieldCircuit omits protected diagrams, message handling rules, fields, tables, exceptions, and normative procedures.
A gateway can create hidden failure modes.Local communication may remain healthy while configuration, forwarding, load, startup order, or the remote segment prevents an end-to-end function.
08 / Evidence
Primary sources.
The official ISO catalog entry is the source for the publication identity and high-level network-layer scope. The architecture shown here is an original teaching abstraction.
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ISO 11783-4:2011 — Network layerInternational Organization for Standardization · Accessed 2026-07-11