Voice; Chapter 17 Voice; Overview; What You Can Do In This Chapter - ZyXEL Communications LTE Series User Manual

17.1 Overview

4G only supports all-IP-based packet-switched telephony services. When Voice service is enabled, the
Zyxel Device supports Circuit Switched FallBack (CSFB) to deliver/receive circuit-switched voice calls
and text messages via a 3G mobile network and then goes back to the 4G LTE network to transmit data
packets.
With the voice service, users do not need a SIP account and SIP server to make phone calls over the
Internet.

17.1.1 What You Can Do in this Chapter

These screens allow you to configure your Zyxel Device to make phone calls over the Internet and your
regular phone line, and to set up the phone you connect to the Zyxel Device.
• Use the Voice Mode screen to enable VoIP or VoLTE services on the Zyxel Device
page 210).
• Use the SIP Account screen to set up information about your SIP account, control which SIP accounts
the phones connected to the LTE Device use and configure audio settings such as volume levels for
the phones connected to the ZyXEL Device
• Use the SIP Service Provider screen to configure the SIP server information, and the numbers for
certain phone functions
• Use the Phone screen to change settings that depend on which region of the world the Zyxel Device
is in (Section 17.4 on page
• Use the Call Rule screen to set up shortcuts for dialing frequently-used (VoIP) phone numbers
17.5 on page
• Use the Call History screen to view a call history

17.2 Voice Mode

Use this screen to enable VoIP or VoLTE services on the Zyxel Device. To access this screen, click Voice >
Voice Mode.
(Section 17.3.3 on page
219).
219).
LTE Series User's Guide
C
H A P T E R
(Section 17.3.1 on page
215).
list(Section 17.6 on page
210
17

Voice

(Section 17.2 on
211).
220).
(Section