Users Manual
https://www.peplink.com 227 Copyright @ 2021 Peplink
Some Internet services need to be specially handled in a multi-WAN environment. The Peplink Balance
can handle these services such that Internet applications do not notice it is behind a multi-WAN router.
Settings for service passthrough support are available here.
Service Passthrough Support
SIP
Session initiation protocol, aka SIP, is a voice-over-IP protocol. The Peplink Balance can
act as a SIP application layer gateway (ALG) which binds connections for the same SIP
session to the same WAN connection and translate IP address in the SIP packets correctly
in NAT mode. Such passthrough support is always enabled and there are two modes for
selection: Standard Mode and Compatibility Mode.
If your SIP server’s signal port number is non-standard, you can check the box Define
custom signal ports and input the port numbers to the text boxes.
H.323
With this option enabled, protocols that provide audio-visual communication sessions will
be defined on any packet network and passthrough the Balance.
FTP
FTP sessions consist of two TCP connections; one for control and one for data. In a multi-
WAN situation, they must be routed to the same WAN connection. Otherwise, problems
will arise in transferring files. By default, the Peplink Balance monitors TCP control
connections on port 21 for any FTP connections and binds TCP connections of the same
FTP session to the same WAN.
If you have an FTP server listening on a port number other than 21, you can check Define
custom control ports and enter the port numbers in the text boxes.
TFTP
The Peplink Balance monitors outgoing TFTP connections and routes any incoming TFTP
data packets back to the client. Select Enable if you want to enable TFTP passthrough
support.
IPsec NAT-T
This field is for enabling the support of IPsec NAT-T passthrough. UDP ports 500, 4500,
and 10000 are monitored by default.
You may add more custom data ports that your IPsec system uses by checking Define
custom ports. If the VPN contains IPsec site-to-site VPN traffic, check Route IPsec Site-
to-Site VPN and choose the WAN connection to route the traffic to.
13.14.5
NTPServer
Peplink routers can now serve as a local NTP server. Upon start up, it is now able to provide connected
devices with the accurate time, precise UTC from either an external NTP server or via GPS and ensuring
that connected devices always receive the correct time.
NTP Server setting can be found via: Network>Misc. Settings>NTP Server