Cisco 1601 - Router - EN, User Manual

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Configuring the ISDN Line B-5
Defining ISDN Service Profile Identifiers
Defining ISDN Service Profile Identifiers
An ISDN service provider, usually a telephone company, can offer a variety of services.
Many providers use service profile identifiers (SPIDs) to identify the device that is using
the ISDN service, similar to the way that the telephone company uses a telephone number
to identify your standard telephone service. If you use a service provider that requires
SPIDs, the provider assigns your ISDN device one or more SPIDs when you first subscribe
to the service. Providers use different numbering schemes, but a SPID is usually a
seven-digit telephone number, plus some optional numbers. The provider also assigns your
device one or two local directory numbers (LDNs), which function as the router telephone
numbers. The LDN is the number that a remote router dials to make a call to the router.
Note SPIDs have significance only at the local-access ISDN interface. The remote router
is assigned a SPID when the ISDN BRI services are ordered for that router.
When your ISDN device accesses the switch to initialize the connection, first it must send
any assigned SPID(s) to the service provider. Otherwise, your ISDN device cannot place or
receive calls. Use the isdn spid command to define the SPID and the LDN on the router for
both ISDN BRI B channels, as follows:
Router(config-if)# isdn spid1 spid-number [ldn]
Router(config-if)# isdn spid2 spid-number [ldn]
Note Although the LDN is usually optional, it might be required so that the router answers
calls made to the second directory number.