VOIP (Callmanager IP Phones) over half duplex wireless link

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Feb 17th, 2010
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I have a remote site that currently has about 30 IP Phones (7940, 7941, 7960, 7961, etc.) that I have call control and voice traffic going to/from our central site backhauled on a T1 Circuit.

I have a new wireless circuit available between these sites that is 25 Mbits but is only half duplex.  My quesiton is will I run into significant voice problems if I backhaul the voice traffice over this new half duplex wireless circuit?

Any thoughts?


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Overall Rating: 3 (3 ratings)
paolo bevilacqua Wed, 02/17/2010 - 11:22
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You should not have any problem.

Bandwith matters, not duplex.

Jonathan Schulenberg Wed, 02/17/2010 - 12:17
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Delay and jitter matter too. How much one-way delay does the wireless link introduce compared to your existing wired circuit? The recommended microphone-to-speaker delay is 150ms. Jitter above 40ms will also be noticable.

David Hailey Thu, 02/18/2010 - 00:05
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To be short and sweet, I'll say the following.  It's not optimal but it'll likely work.  For reference, I had a customer doing Voice over Satellite with multiple hops and retransmission points across the world and utlimately entering into an encrypted tunnel leveraging in Internet connection spanning about 10 states - the delay RTT was over 700 milliseconds.  It wasn't always pretty and there were problems, but it worked.

No guarantees on anything, but just some perspective.

HTH - if so, please rate.


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