Question About Octo Line DN's

Answered Question
Feb 5th, 2009
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I just upgraded to the latest IOS and I'm fooling around with the new Octo line DN feature.

After setting up an ephone as an octo line, I'm unable to setup a button with an overlay. It says that is it not supported.?

Is this true? If so, is there any work around?

I'm trying to put my main extension as well as an intercom externsion on the same button.

I.E: button 1o101,1101



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Marcos Hernandez Thu, 02/05/2009 - 08:50
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Correct Brian. Octo lines and overlays are mutually exclusive. Sometimes you can't bake your cake and eat it too :-)


jaydien1358 Thu, 02/05/2009 - 13:24
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I'm confused about what the advantage is then for an Octo line DN. I just thought of an Octo DN as 4 times as powerful as a Dual-Line DN. And you can do overlays with a dual line? So why wouldn't you be able to with an Octo as well?

What is the logic behind disabling it on the Octo Line?


Marcos Hernandez Thu, 02/05/2009 - 13:53
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There are some reasons why an octo line is better than overlaying dual line ephone-dn's:

1) First, the 8 channels of an octo line can be shared between different phones, whereas with dual lines the phone owns both channels (forcing the call to hunt to the next dn, effectively cutting the real call capacity in half).

2) When you do a shared line with octo line, you also get "Line in Use" indication. This doesn't happen with overlays.

3) You can assign the octo dn to as many phones as you want, even though you will have only 8 simultaneous calls (this should be more than enough for most SMB deployments).

4) If you need more simultenous call capacity in a "ring all" fashion, you can use call blast hunt groups.

5) Ephone dn's come at a premium (they are not infinite and limited by license capability). This means that if you start overlaying left and right, you might run ou of ephone dn slots.

6) Octo lines can be use for other things such as conferencing.

This doesn't mean that we should completely eliminate overlay dn's. For example, you still need them if you want to add a SPA525 to shared line, as this phone doesn't support octals yet. But in general, I think the need for overlays will decline given the amount of options in our toolkit.



jaydien1358 Fri, 02/06/2009 - 05:58
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Ok. I think I'm starting to get it. After reading over your response like 6 times. :)

So is it safe to assume that OctoLine DN's are only really appropriate if you have a phone with multiple buttons? 5 or more let's say. Other wise you can't really take advantage of the 8 channels because of not being able to use overlays.

Becasue I always thought of overlays as a way to overcome the limitation of, for example, a two button phone but still allowing access to more than just 2 DN's.



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