Migrating from on-prem SIP and Internal Extensions

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We are migrating to RC from an Avaya on-premise SIP phone system which featured internal extensions and requiring "9" to dial an outside line. While I know the dial 9 requirement is an antiquated feature it raised the question of how we would handle internal extension dialing. For example, we have a lot of extensions that begin with "8" and I could see a potential problem down the road if someone is trying to dial an actual outside number that happens to share it's first 3 or 4 digits with an internal extension... This is the case where the 9 prefix does come in handy.

I contacted RC support about this and they said the feature is not available to create prefixes but that it may become an added feature in the future.

I see one potential solution being that we add a "1" in front of each internal extensions, because there are no area codes that begin with 1, but I was hoping for input from anyone else who may have migrated from an old school phone system that required the 9 prefix on outbound calls
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Posted 2 years ago

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don't worry about that. it'll detect you're dialing an internal extension. I would caution against using any extension that has 911 in it, like 9110-9119, or 4911, 3911, etc, just in case people accidentally miss a number when dialing.
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John Salewski

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JD is giving good advice regarding staying clear of extensions with a 911 in them... we came from an old Nortel system where dialing out required a prefix.  Once over to RC, you can just dial your extension and wait 3 seconds (it'll call the extension) or you can dial and hit "send / ok / call / etc" without the wait.  Works quite nicely.
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Jeff Salisbury, Champion

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We moved off of a Cisco PBX that also used 9 to dial an outside line, and I had the same concerns that you do. Fortunately it hasn't been an issue. We did tell users during initial training to not pause during dialing an outside line, otherwise the system will think you are trying to dial an extension.
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Thank you all for the input.

We definitely do not and would not have any extensions with 911 in it, ours are 4 digits long and begin with either an 8 or a 1.

I wasn't aware of any of the features built into the RC platform like the autodetecting, or the fact you can dial and wait 3 seconds... I would hope most people would type out their outside call fast enough to avoid a potential conflict haha.
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I'd say it's less of a feature and more the case of RC implementing very basic behaviour to accept any phone number of any length, waiting a few seconds and then dial the number.

This has a few disadvantages. Firstly, a user calling an internal extension will have to wait a few seconds before the call is connection and secondly, if the user pauses whilst entering an external number  (can be an issue when entering long international numbers), the call will fail as the number is sent incomplete. User training can mitigate these issues but still frustrate our users!

These shortcomings are actually down to the way RC provision their IP phones (in particular the phone dial plan). To keep things simple, the phone accepts any number of any length, waits a few seconds then send the number to RC. RC don't provide an ability to customise these dial plans unless you use an unlocked or 3rd party phone.

In contrast, most on premise platforms would allow configuration of a dial plan which would specifically detail expected lengths of numbers for internal extensions, local number etc.

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Brad Giannini

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H_203RC we just did what you are proposing, we moved off an Avaya on-premise PBX with the same setup - dial 9 and everyone had 4 digit extensions.  As stated above, RingCentral doesn't care if your extensions are 4, 5, 6 digits or all three (we're currently using both 4 digit and 5 digit extensions).  I don't consider this a short coming because now I can add as many users as I want, Keep our old numbering plan for our legacy users and add infinitely more without having to have everyone change their extensions that they had in the legacy system.  

The pause while dialing only becomes an issue if you're dialing very slowly, pause, or get interrupted while the phone is off hook.  If the phone is on hook and you're dialing and pause, it'll wait until you go off hook or press "dial".  We only have about 1/3 of our users on hard phones, the rest are on soft phones so this isn't an issue for them, they are usually typing the other employee's name and dialing them directly or using the click to dial features that the soft phone offers.  Either way, it takes a little training, but the learning curve is very low.