Yealink VC110, Administrator'S Manual

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Administrator‘s Guide for Yealink VC110 Video Conferencing Endpoint
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Restricted Cone:
A restricted cone NAT is one where all requests from the same internal IP address and
port are mapped to the same external IP address and port. Unlike a full cone NAT, an
external host (with IP address X) can send a packet to the internal host only if the
internal host had previously sent a packet to IP address X.
Port Restricted Cone:
A port restricted cone NAT is like a restricted cone NAT, but the restriction includes port
numbers. Specifically, an external host can send a packet, with source IP address X and
source port P, to the internal host only if the internal host had previously sent a packet to
IP address X and port P.
Symmetric:
A symmetric NAT is one where all requests from the same internal IP address and port,
to a specific destination IP address and port, are mapped to the same external IP
address and port. If the same host sends a packet with the same source address and
port, but to a different destination, a different mapping is used. Furthermore, only the
external host that receives a packet can send a UDP packet back to the internal host.
The endpoint can send keep-alive packets to NAT device for keeping the
communication port open.
The Keep alive interval parameter on the endpoint is described below:
Parameter Description Configuration Method
Keep Alive
Interval
Configures the
keep-alive interval
(in seconds) that
the endpoint
sends to the NAT device to keep
the communication port open. So
that NAT can continue to function
for SIP account.
Default: 30
Web User Interface
To configure the keep-alive interval via web user interface:
1. Click on Account->SIP Account.