1.2 Important Notice for Subscription and Installation
1.2.1 Port Requirements
Required Ports for Each Channel
When configuring a router with NAT enabled, you need to secure a certain number of ports for each SIP and
RTP/RTCP channel. For RTP/RTCP, the number of required ports is double the number of activated SIP CO
lines (Ch). For SIP signaling, the number of required ports is always one regardless of the number of activated
SIP CO lines (Ch).
<Example>
If 4 SIP CO line channels are activated, you need the following number of ports:
Protocol Type
Required Port
RTP
4
RTCP
4
SIP
1
Total
9
1.2.2 Firewall Requirements
If the VoIP network contains a firewall, you must configure the firewall to allow VoIP packets to pass through
certain ports of the ports listed below without being blocked by filtering. The ports for which you need to
configure the firewall may vary depending on the network conditions.
For more information, consult your network administrator.
[IP Packets to V-SIPGW16 Card]
Port
TCP/UDP
Default Port No.
SIP Client Port
UDP
35060
STUN Client Port
UDP
33478
NAT Voice (RTP) UDP Port
UDP
16000 to N
DNS (Client) Port
UDP
30053
[IP Packets from V-SIPGW16 Card]
Port
TCP/UDP
Default Port No.
SIP Server Port
UDP
5060
Registrar Server Port
UDP
5060
STUN Server Port
UDP
3478
Manual DNS Server Port
UDP
53
Document Version 2008-11
Programming Manual for Virtual SIP CO Line Card
7
1.2.2 Firewall Requirements