User's Manual

Chapter 28 Product Specifications
P-2612HW Series User’s Guide
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Call forwarding With this feature, you can set the ZyXEL Device to forward calls to a
specified number, either unconditionally (always), when your number
is busy, or when you do not answer. You can also forward incoming
calls from one specified number to another.
Caller ID The ZyXEL Device supports caller ID, which allows you to see the
originating number of an incoming call (on a phone with a suitable
display).
REN A Ringer Equivalence Number (REN) is used to determine the number
of devices (like telephones or fax machines) that may be connected
to the telephone line. Your device has a REN of three, so it can
support three devices per telephone port.
Dynamic Jitter
Buffer
The built-in adaptive buffer helps to smooth out the variations in
delay (jitter) for voice traffic. This helps ensure good voice quality for
your conversations.
Multiple SIP
Accounts
You can simultaneously use multiple voice (SIP) accounts and assign
them to the telephone port.
Multiple Voice
Channels
Your device can simultaneously handle multiple voice channels
(telephone calls). Additionally you can answer an incoming phone call
on a VoIP account, even while someone else is using the account for a
phone call.
Voice Activity
Detection/Silence
Suppression
Voice Activity Detection (VAD) reduces the bandwidth that a call uses
by not transmitting when you are not speaking.
Comfort Noise
Generation
Your device generates background noise to fill moments of silence
when the other device in a call stops transmitting because the other
party is not speaking (as total silence could easily be mistaken for a
lost connection).
Echo Cancellation You device supports G.168, an ITU-T standard for eliminating the
echo caused by the sound of your voice reverberating in the
telephone receiver while you talk.
QoS (Quality of
Service)
Quality of Service (QoS) mechanisms help to provide better service
on a per-flow basis. Your device supports Type of Service (ToS)
tagging and Differentiated Services (DiffServ) tagging. This allows
the device to tag voice frames so they can be prioritized over the
network.
Table 166 Voice Features