Cisco 700 series, Installation Manual

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C H A P T E R
ISDN and Analog Telephone Devices 4-1
4
ISDN and Analog Telephone
Devices
This chapter describes how to connect an ISDN or analog telephone to a Cisco 700 series
router and how to configure the router to support that telephone. An ISDN telephone can
be connected to the ISDN S/T port of any Cisco 700 series router. An analog telephone can
be connected to a Cisco 765, Cisco 766, Cisco 775, or Cisco 776 router basic telephone
service port (also known as “plain old telephone service” or “POTS” port).
Note
During a voice call, if the remote party hangs up the receiver and your receiver
remains off-hook, you will hear a fast busy tone after 30 seconds.
Connecting an ISDN (Digital) Telephone
You can connect an ISDN telephone to any Cisco 700 series router with an S/T port. The
ISDN telephone communicates over the same ISDN line the router uses to send and receive
data. ISDN telephones are available in two basic models, self-powered (described in the
section “Connecting a Self-Powered Digital Telephone”) and with an independent power
supply (described in the section “Connecting a Digital Telephone with an External Power
Supply”).
Warning
This equipment contains a ring signal generator (ringer), which is a
source of hazardous voltage. Do not touch the RJ-11 (phone) port wires
(conductors), the conductors of a cable connected to the RJ-11 port, or the
associated circuit-board when the ringer is active. The ringer is activated
(indicated by a clicking sound) by an incoming call.