IBM SC30-3681-08 manual Encryption enabled, will encrypt all transmitted data, Lmi

Con®guring Frame Relay Interfaces

congestion-monitor

Enables the congestion monitoring feature. This feature allows a circuit's information rate to vary in response to congestion between the minimum information rate and the line speed.

Note: The circuit monitoring feature overrides the congestion monitoring feature if there is a con¯ict when both are enabled. The default setting for this feature is enabled.

For additional information on congestion monitoring, see ªCongestion

Monitoringº on page 400.

dn-length-®eld

Supports inter-operation with implementations of DECnet Phase IV over Frame Relay that require a length ®eld to precede DECnet packets in Frame Relay frames. Enabling dn-length-®eld causes Frame Relay to insert a length ®eld into transmitted frames containing DECnet packets and to remove the length ®eld from received frames containing DECnet packets. This option is disabled by default. By default, Frame Relay will neither insert nor attempt to remove the length ®eld.

	Note: This option is presented as a con®guration option only when the
	router software contains the DECnet Phase IV protocol.
encryption
	Enables encryption on the interface. All VCs that are con®gured as
	encryption enabled, will encrypt all transmitted data.
lmi	Enables management activity.
	After issuing the enable lmi command, use the set lmi-typecommand to
	select the management mode for your Frame Relay interface. See
	ªEnabling Frame Relay PVC Managementº on page 403. The system
	defaults to ANSI T1.617 Annex D management.
	Use the enable lmi command to resume LMI management if you have
	previously disabled Frame Relay management.
	LMI only provides information about PVCs on an interface, so it does not
	need to be enabled if only SVCs are used unless it is required by the
	network. Q.922 determines the usability of all SVCs on an interface and is
	an indicator of the state of the interface itself. When both PVCs and SVCs
	are on an interface, LMI and Q.922 may be active at the same time.

lower-dtr

This parameter determines how the data terminal ready (DTR) signal is handled for leased serial-line interfaces that are disabled. It is not supported on Frame Relay dial circuit interfaces. If this parameter is set to ªdisabledº (the default), the DTR signal will remain raised when the interface is disabled.

When lower-dtr is enabled, DTR will be lowered when the interface is disabled. This behavior may be desirable in situations where the interface has been con®gured as an alternate link for WAN Reroute and the interface is connected to a dial-out modem which maintains its dial connection based on the state of the DTR signal.

If this feature is enabled and the interface is disabled, the DTR signal is low and the modem keeps the dial connection down. When the interface is enabled, due to a WAN Reroute backup scenario, DTR is raised and the

Chapter 31. Con®guring and Monitoring Frame Relay Interfaces 417