User`s guide

6238-A2-ZB20-10 6238 Wi-Fi Router with VOIP User’s Guide 63
• Preferred Codec— Select the voice encoder that you prefer. This does not
guarantee that this encoder will be used, but will be taken into consideration
when deciding which voice encoder to use. Each voice encoder varies by the
amount of compression on the voice.
• Packetisation Time (in milliseconds)— This is how often a packet should
be sent. This can increase or decrease the time duration between each packet
sent.
z VAD State (Voice Activity Detection)— Enabling this will control voice
information to be sent based on voice activity, which can reduce voice traffic.
z ECAN State— Echo Canceller— Enabling this feature will cancel out any
echo in the call.
• DTMF Relay State— Select between voice band and RFC 2833. RFC 2833
describes how to carry out DTMF signaling, other tone signals, and telephony
events in RTP packets.
• Fax Mode— Select between none or voice band data.
o None: Fax data is being processed as audio using an audio codec. If
the codec is not suitable for fax signal, then fax transmission will fail.
o Voice Band Data: Fax data is being sent processed as audio using an
audio codec, and if the codec is not suitable for fax signal, IAD will
automatically change to a suitable codec for fax transmission.
• SIP Re-register Timer (in seconds)— The amount of time before
registration is required again.
z Session Expire Timer (in seconds)— When a connected call session will be
dropped if the keep alive facility is down.
• Signaling / Voice TOS— Type of service for signaling and voice. A
signaling transmission is used for building a voice connection. Voice TOS is
used for voice transmission. Each call has two parts—first part involves the
signaling transmission when a call is made or received. The second part is
when the call is connected, it transfers voice in voice transmission.
• Inter / Critical Digit Timer (in seconds) — Inter-digit timer (IDT) is used as
timeout check between each digit dialed, while the critical digit timer (CDT)
is used for "almost completed" dialing to wait for more digits. Essentially,
CDT is the time that the device waits after the digits are dialed before it dials
the numbers.
z Do Not Disturb— This call-filtering feature prevents incoming calls from
coming through. Callers will hear a busy signal when you have the Do Not
Disturb featured enabled.
z Answer Only— This call-filtering feature disables the ability to make
outgoing calls. You can only accept incoming calls after you turn on this
feature.
z Pass “#” as Dialing Digit –if this is disabled, dial “#” to terminate the
dialing. When enabled, dial the “*” to terminate the dialing and then IP
dialing will be disabled.
• Prefix for Switch VOIP to PSTN— One of the ways that a phone number
can be dialed using PSTN (and not VoIP). It is the number prefix that you
must enter in order to switch from using VOIP to your regular phone (public
switched telephone network).