ZyXEL Communications ADSL VoIP IAD with 802.11g Wireless 2602HW Series - Manual (Page 140)

Prestige 2602HW Series User’s Guide
140 Chapter 10 Voice Screens
10.4 Quality of Service (QoS)
Quality of Service (QoS) refers to both a network's ability to deliver data with minimum delay,
and the networking methods used to provide bandwidth for real-time multimedia applications.
10.4.1 Type Of Service (ToS)
Network traffic can be classified by setting the ToS (Type Of Service) values at the data
source (for example, at the Prestige) so a server can decide the best method of delivery, that is
the least cost, fastest route and so on.
Min-SE When two SIP devices negotiate a SIP session, they must negotiate a common
expiration time for idle SIP sessions. This field sets the shortest expiration time that
the Prestige will accept. The Prestige checks the session expiration values of
incoming SIP INVITE requests against the minimum session expiration value that
you configure here. If the session expiration of an incoming INVITE request is less
than the value you configure here, the Prestige negotiates with the other SIP
device to increase the session expiration value to match the Prestige’s minimum
session expiration value.
RTP Port Range Real time Transport Protocol is used to handle voice data transfer. Use these fields
to configure the Prestige’s listening port range for RTP traffic. Leave these fields
set to the defaults if you were not given a range of RTP ports to use.
Preferred
Compression
Type
Use this field to select the type of voice coder/decoder (codec) that you want the
Prestige to use. G.711 provides higher voice quality than G.729 but requires
64kbps of bandwidth while G.729 only requires 8kbps.
Select G.711>G.729 if you want the Prestige to first attempt to use the G.711
codec and then the G.729 codec if the peer is not set up to use G.711.
Select G.711 only if you want the Prestige to only use the G.711 codec when
making VoIP calls. You will not be able to connect to a peer that is not set up to use
G.711.
Select G.729>G.711 if you want the Prestige to first attempt to use the G.729
codec and then the G.711 codec if the peer is not set up to use G.729.
Select G.729 only if you want the Prestige to only use the G.729 codec when
making VoIP calls. You will not be able to connect to a peer that is not set up to use
G.729.
DTMF Mode The Dual Tone Multi-Frequency (DTMF) mode sets how the Prestige handles the
tones that your telephone makes when you push its buttons. It is recommended
that you use the same mode that your VoIP service provider uses.
Select RFC 2833 to send the DTMF tones in RTP packets.
Select PCM (Pulse Code Modulation) to include the DTMF tones in the voice data
stream. This method works best when you are using a codec that does not use
compression (like G.711). Codecs that use compression (like G.729) could distort
the tones.
Select SIP INFO to send the DTMF tones in SIP messages.
Back Click Back to return to the previous screen.
Apply Click Apply to save your changes back to the Prestige.
Cancel Click Cancel to begin configuring this screen afresh.
Table 34 Voice Advanced Setup (continued)
LABEL DESCRIPTION