ZyXEL Communications LTE5121, User Manual

Page: 169 / 234

Chapter 17 VoIP
LTE-5121 User’s Guide
169
Start Port
End Port
Enter the listening port number(s) for RTP traffic, if your VoIP service provider
gave you this information. Otherwise, keep the default values.
To enter one port number, enter the port number in the Start Port and End
Port fields.
To enter a range of ports,
• enter the port number at the beginning of the range in the Start Port field.
• enter the port number at the end of the range in the End Port field.
DTMF Mode Control how the LTE Device handles the tones that your telephone makes when
you push its buttons. You should use the same mode your VoIP service provider
uses.
RFC2833 - send the DTMF tones in RTP packets.
PCM - send 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.726) can distort the tones.
SIP INFO - send the DTMF tones in SIP messages.
Transport Type
Transport Type Select the transport layer protocol UDP or TCP (usually UDP) used for SIP.
FAX Option This field controls how the LTE Device handles fax messages.
G711 Fax
Passthrough Select this if the LTE Device should use G.711 to send fax messages. The peer
devices must also use G.711.
T38 Fax Relay Select this if the LTE Device should send fax messages as UDP or TCP/IP packets
through IP networks. This provides better quality, but it may have inter-
operability problems. The peer devices must also use T.38.
Outbound Proxy
Enable Select this if your VoIP service provider has a SIP outbound server to handle
voice calls. This allows the LTE Device to work with any type of NAT router and
eliminates the need for STUN or a SIP ALG. Turn off any SIP ALG on a NAT router
in front of the LTE Device to keep it from re-translating the IP address (since this
is already handled by the outbound proxy server).
Server Address Enter the IP address or domain name of the SIP outbound proxy server.
Server Port Enter the SIP outbound proxy server’s listening port, if your VoIP service
provider gave you one. Otherwise, keep the default value.
QoS Tag
SIP TOS Priority
Setting Enter the DSCP (DiffServ Code Point) number for SIP message transmissions.
The LTE Device creates Class of Service (CoS) priority tags with this number to
SIP traffic that it transmits.
RTP TOS Priority
Setting Enter the DSCP (DiffServ Code Point) number for RTP voice transmissions. The
LTE Device creates Class of Service (CoS) priority tags with this number to RTP
traffic that it transmits.
Timer Setting
Expiration
Duration Enter the number of seconds your SIP account is registered with the SIP register
server before it is deleted. The LTE Device automatically tries to re-register your
SIP account when one-half of this time has passed. (The SIP register server
might have a different expiration.)
Register Re-send
timer Enter the number of seconds the LTE Device waits before it tries again to register
the SIP account, if the first try failed or if there is no response.
Session Expires Enter the number of seconds the LTE Device lets a SIP session remain idle
(without traffic) before it automatically disconnects the session.
Table 69
VoIP > SIP > SIP Service Provider (continued)
LABEL DESCRIPTION