Yealink VC110, Administrator'S Manual

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Administrator‘s Guide for Yealink VC110 Video Conferencing Endpoint
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Check whether the far site rejects your call.

Check whether the firewall blocks the inbound traffics from the other site.

Check whether the far site has already up to maximum call-in limitation.

If the near site is forced to use encryption, ensure that the far site enables
encryption too. For more information on call encryption, refer to
Secure Real-Time
Transport Protocol on page 215 and H.235 on page 218 .

Ensure that the far site supports the same call protocol as the near site.

Ensure that at least one call protocol is enabled on both sites. For more information,
refer to
Configuring SIP Settings on page 111 and Configuring H.323 Settings on
page 115 .

Ensure that the network is connected correctly.

Ensure that the network is configured correctly. For more information, refer to
Configuring LAN Properties on page 56 .

Ping the IP address of the far site. Contact your system administrator if it fails. For
more information, refer to
Using Diagnostic Methods on page 238 .

Check whether the network is available.

Check whether the LAN property is configured correctly. For more information on
LAN property configuration, refer to
Configuring LAN Properties on page 56 .

Check whether the endpoint has enabled the hide IP address feature. For more
information on disabling the hide IP address feature, refer to
Hide IP Address on
page 153 .

Check whether the endpoint has configured firewall and NAT correctly. For more
information on, refer to
Configuring the Endpoint for Use with a Firewall or NAT on
page 87 .

Check whether the network is available and the LED indicator on the left of the
Internet port illuminates green.

Try to use the low speed connection to check whether packets are lost. Deficient
bandwidth is an important reason for packet loss.

Check the configuration of the network speed and duplex mode on the endpoint,
switch and router.