User Manual

Network architecture
LonWorks architecture (ALN)
14
CM110664en_07 197 | 353
Key
R Repeater, e.g., LonWorks physical repeater
B Bridge, e.g., L-Switch (Loytec)
RT Router, e.g., LonWoks router
GW Gateway, e.g., PXC..., RXZ03.1
See
LonWorks networks Checklist (CA110335).
A trunk holds all devices that can communicate with each other directly or via
repeater, bridge or router. The term trunk is specific to the Desigo system. One
trunk corresponds to one LonWorks project. Trunks can be connected via
gateways.
A trunk can be divided into segments. The segments are connected by a router.
If there are no routers, the trunk comprises only one segment.
The physical segment is the communication medium. LonWorks devices are
connected to the physical segment. One segment can be divided by bridges or
repeaters into several segments. The number of devices per physical segment
is limited.
System devices
The gateway links trunks. It operates on the application layer of the ISO/OSI
layer model. The following LonWorks gateways are available:
The RXZ03.1 point coupler provides a fixed number and type of LonTalk
network variables (NV). Each side of the point coupler belongs to a trunk or
LonWorks project. The point coupler can be used to implement time-critical
connections between two trunks. The point coupler integrates third-party
devices that have been engineered with a different tool.
Loytec L-Proxy and Sysmic XFM-LL are freely programmable point couplers.
The XFM-LL device may be used, when depicted like a standard third-party
device (configuration via its own tool).
The PXX-L.. extension modules let you connect LonWorks devices to the
PXC..D modular series.
The LonWorks router operates on the network layer of the LonWorks protocol.
It filters data packets based on their subnet ID or group ID. Subnets or groups
must never be defined across a router, that is, the subnet IDs and group IDs at
each end of the router must never be the same. Routers are used where there
is heavy local network traffic. They allow the unloading of unaffected devices
from the network traffic. In Desigo there are no large LonWorks networks, as
the FLN is divided into trunks. Routers are only required in exception cases.
Trunk
Segment
Physical segment
Gateway
Router