Echelon LNS - Manual (Page 46)

LNS Programmer's Guide 32
Applications access the services provided by the LNS Server using the LNS Object
Server. The LNS Object Server is a COM server that provides an interface, independent
of any specific programming language, to the LNS Server and the LNS database.
The LNS Object Server provides the resources to manage and record the configuration
information for any L ON W ORKS network within the following constraints:
• Up to 100 open networks per application when operating in server-independent
mode, and up to 50 open networks per application when operating in server-
dependent mode. The differences between the server-independent and server-
dependent modes are described later in this chapter in the LNS Clients section.
• Up to 10 remote LNS client applications, and an unlimited number of local
applications, per network. These applications may invoke services on the LNS
Server, provide their own subsystem-specific services, properties and events, as
well as act as application nodes in the network. Some applications can open more
than one network at the same time.
• Up to 1,000 channels.
• Up to 1,000 routers.
• Up to 32,385 application devices.
• There are up to 12,288 network variable selectors in each network. A network
variable's selector is a 14-bit number used to identify connected network
variables. All network variables in a given connection use the same network
variable selector. The LNS Server shares a network variable selector among
connections if the connections share one or more network variables. LNS can
intelligently reuse network variable selectors; thus, an LNS-managed network is
not limited to 12,288 connections.
• Up to 4,096 network variables on each host-based device, and up to 62 network
variables on each device hosted on a Neuron Chip or Smart Transceiver.
LNS Object Server Hierarchy
The LNS Object Server defines a set of objects, properties, methods and events that
represent the physical attributes of your network and their configurations. The objects
are grouped together in a hierarchical fashion, such that the ObjectServer object (i.e.
the object representing the LNS Object Server) is at the top of the hierarchy.
The ObjectServer object contains a collection of Network objects, each of which
represents a network defined in the global database that the LNS Object Server can
administer. Each Network object contains a System object representing the network’s
system, and each System object contains a set of Subsystem objects that represent
logical or physical partitions of that particular network. Each
Subsystem
object contains
a collection of
AppDevice
objects, which represent the application devices defined in that
subsystem, and
Router
objects, which represent the routers defined in that subsystem.
For example, you could set up a network to control a building with 3 floors. You could
define 3 subsystems within the network, so that you could logically group the devices and
routers on each floor separately. You could also set up additional subsystems
representing different rooms on each floor of the building, as your network design
requires.