Huawei EchoLife ET323, Руководство пользователя

Страница: 43 / 64

EchoLife ET523 IP Phone User Manual 4 Configuration Guide
38
Field Description
Local RTP port This parameter defines the local RTP-RTCP port pair used to
listen and transmit messages. It is the base RTP port for channel
0. When it is configured, channel 0 will take this port_value as
RTP port value, and por1 as the RTCP port value;
channel 1 will take por2 as the RTP port value and
por3 as the RTCP port value. The default value is
5004 .
Use Random
Port When this parameter is set to Yes , the 523 will force the random
generation of both the local SIP and RTP ports. This is usually
necessary when multiple ET523s are behind the same NAT.
The default value is
No .
Keep-alive
interval This parameter specifies how often the ET523 sends a blank
UDP packet to the SIP server in order to keep the “hole”on the
NAT router open. The default value is 20 seconds. The
minimum value is
10 .
Use NAT IP NAT IP address used in the SIP/SDP message. The default
setting is blank.
STUN Server IP address or Domain name of the STUN server. The STUN
resolution result will display in the STATUS page of the Web
configuration page. STUN NAT resolution does not work for
symmetric NAT. STUN is a client-server protocol. A VoIP
phone or software package may include a STUN client, which
will send a request to a STUN server. The server then reports
back to the STUN client what the public IP address of the NAT
router is, and what port is opened by the NAT to allow
incoming traffics back to the network.
Firmware
Upgrade and
Provisioning This radio button will enable the ET523 to download the
firmware or configuration files through either HTTP or local
TFTP server.