Devices on separate channels cannot communicate unless the channels are connected by a router or an i.LON 1000 server. This section describes how to create a router in a LonMaker network design. See Creating an i.LON 1000 Internet Server for instructions on that process.
A single router may be used to connect two channels, or you may use multiple routers, called redundant routers, between the same pair of channels. Redundant routers provide fault tolerance by providing more than one routing path from one channel to another. They are also required when all devices on a given channel may not be able to hear one another (referred to as an ear shot problem), for example on a radio frequency channel. For a router to function as a redundant router, the router must be configured to be a Configured router (this is the default).
Routers, like devices, are created in two steps: definition and commissioning. To create a router, follow these steps:
1. Create the channels you want to connect with the new router or make sure that they already exist somewhere in the drawing. The channels being connected do not have to be on the same page as the router.
2. Drag a Router shape from a LonMaker stencil to the drawing. The New Router Wizard appears.
3. Enter the following information:
Router Name The name of the router. This name must be unique within the network and may be up to 85 characters long.
Commission Device As when defining a device, you may choose to define and commission the router in the same step. If the LonMaker tool is not attached to the network, the Neuron ID can only be entered manually.
You can control the default setting for this field from the LonMaker menu by selecting Network Properties, clicking LonMaker Options tab, and then selecting Devices.
5. Enter the following information:
Xcvr Type Specifies the channel type for the channels listed in the Name list. Only channels with the specified channel type will be displayed. Some router shapes will limit the channel types you can select. Select All in the Xcvr Type to view all defined channels. The default setting is All.
Name Lists all of the channels for the specified channel type. Select the two channels you wish to link with the router. The same channel cannot be selected in both fields. If one or both of the channels you choose does not have a representation in this subsystem, a shape for it will automatically be added when the router definition is complete. 6. Click Next. The Specify Router Properties window appears:
7. Enter the appropriate information in the following fields:
Location Specifies the router’s location string. This information may be entered as an ASCII text string with up to 6 characters or as a hex string with up to 12 hex digits. It documents the router’s location within the network. This information is not used by the LonMaker tool, but may be useful for network recovery if you lose your LonMaker drawing and database. For example, you can put an abbreviation of the subsystem name or a subsystem number in Location. Ping Interval Specifies the ping interval for this router. The ping interval
determines how often a router is pinged by the LNS Server to ensure it is still in communication with the network. Set the ping interval based on the expected attachment of the router to the network. If you expect that the router will never move on the network, select Never. Set the interval to 15 minutes for a router you expect will move rarely, to 2 minutes for a router you expect will move fairly often, and to 1 minute for a router you expect will move very often. The default ping interval is Never.
Any errors detected by pinging a router are displayed on the router shape in the LonMaker drawing. See Using
Description Displays a brief description of the router. This field has no effect on network operation and may be used to provide additional documentation for as-built reports.
8. Click Next. The Advanced Router Properties window appears.
9. Enter the following information:
Router Name Specifies the name of the router. This field is read-only.
Router Type Specifies the router type. You can configure a router as one of the following types: • Configured router • Learning router • Repeater • Permanent repeater • Bridge • Permanent bridge
The default type is Configured, which is the recommended setting for optimal performance and reliability.
routing tables. Configured routers have their routing tables in non-volatile memory, and thus are retained after a reset. These tables control forwarding of subnet and group-addressed messages and are managed automatically by the LonMaker tool. The LonMaker tool is aware of the network topology, and sets up the subnet and group routing tables accordingly. A configured router is the recommended router type to use, since it allows the LonMaker tool to optimize network traffic and to automatically determine the channel to which each device is attached. Configured routers also support the use of redundant routers (multiple routers connecting the same pair of channels), which provide for redundant message paths and greater system reliability. A Learning Router, like a configured router, determines which packets to forward based on the subnet routing tables. A learning router always forwards all group-addressed messages. Whenever a router receives a packet with a destination address using a subnet ID, it uses the subnet ID to
determine whether to forward the packet. Learning routers have their routing tables in volatile memory, so after a reset the router forwards packets addressed to all subnets in the application domain. Whenever a learning router receives a packet from one of its channels, it uses the source subnet ID to learn the network topology. It sets the corresponding routing table entries to indicate that the subnet in question is to be found in the direction from which the packet was received.
A Repeater forwards all valid packets received on one channel to the other channel.
A Permanent Repeater behaves similarly, but its type cannot be changed after creation.
A Bridge forwards a valid packet received on one channel to the other channel if the packet is sent on a domain to which the bridge belongs. In a single domain network, a bridge functions essentially the same as a repeater. A Permanent Bridge behaves similarly, but its type cannot be changed after creation.
Authentication Indicates whether authentication is enabled for LonMaker communication with this router. Authentication can only be enabled for a router if
authentication is enabled for the LonMaker tool in the Authentication dialog of Network Properties.
Priority Indicates whether priority is used for this router on either or both of its channels, and whether the priority slot will be determined automatically or manually.
If you chose to Commission the Router now, the commissioning dialogs appear. 10. Click Finish to add the router shape to the LonMaker drawing.