See “Set” on page646 for more information about priority.
Cost Control Over Demand Circuits
Dial-on-demand circuits always appear to be in the Up state to the protocols. Most
protocols send out periodic routing information that could cause the router to dial
out each time the routing information is sent over dial-on-demand circuits. Tolimit
periodic routing updates, configure IP and OSI to use only static routes and disable
the routing protocols (RIP,OSPF) over the dial circuits. If you are using IPX,
configure static routes and services and disable the routing protocols (RIP,SAP)
over the dial circuits. Another option is to configure low-frequency RIP and SAP
update intervals, although this does not prevent RIP and SAP from broadcasting
routing information changes as they occur. Youshould also enable IPX Keepalive
filtering, which prevents keepalive and serialization packets from continually
activating the dial-on-demand link.
Caller ID and LIDS
If the ISDN service provides the ANI or CallerID (CLID) service by providing the
Calling Party Number (CPN) in the ISDN setup message, you can use it to match
up dial circuits to the appropriate caller. Otherwise, you must either use a
proprietary line identification protocol (LID) or provide circuits that are “ANY
INBOUND”.
The LID protocol uses the inbound destination in the dial circuit configuration and
LID received to match the calling dial circuit to the receiving dial circuit. The LID
protocol is a brief identification protocol initiated by the caller and answered by the
receiver. If the caller does not provide the LID message, the receiver may reject the
call, if any_inbound dial circuit is not configured. LID exchanges occur on the
B-channel.
When connecting to routes that do not support logical ids (LIDS), you can suppress
the LID exchange using the config option under the individual dial circuit.
config> set lid_used no
On the incoming side, if lid_used=no, the call is completed and the IBM 2210 does
not wait for the LID to come on the B_channel. Instead, the IBM 2210 tries to use
the callerID received. If there is no match on the callerID the IBM 2210 checks to
see if an any_inbound dail circuit is available. If no any_inbound circuit is available
the call is rejected.
On the outgoing side, PPP/FR selftest starts immediately, after B-Channel is
allocated.
ISDN Cause Codes
This ISDN implementation specifies a cause code that will stop the router from
attempting to establish a connection through an ISDN interface. If the application
retries, the router again attempts to establish a connection through this interface
and will succeed if the original problem has been corrected. If during the retry the
router encounters the same cause code, the application will not attempt further
connection processing through this interface.
Cause code interpretations:
Using ISDN
614 MRS V3.2 Software User’s Guide
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