can i just configure a calling search space on the VM ports on my CUCM to do the same thing as configuring restriction tables on my Unity Connection servers?
to my mind they both achieve the same result, which is to stop calls being made by Unity Connection (ie users calling or forwarding to premuim or international numbers etc from within the Unity system).
If so, most people would find it easier to use the CSS on CUCM, as that is a more widely used and understood method of restricting calls.
Just a note here:
I typically go with what you and Rob described which is to set the restrictions for VM at the CUCM CSS level on the VM ports. However, that doesn't mean that the Restriction Tables are moot. For example, if you go with default restriction tables then most digit patterns users enter for transfers, notification devices, and so forth will be allowed - as in, Unity will be allow the digit string to be entered. However, any patterns that are allowed by Unity and trigger a voice port to initiate a call will then be subject to the restrictions of the CSS assigned to the VM ports. So, from a user perspective - they may think something is OK when it is not. This is more of an end user education issue but it's good to know.
If you find that you need to have different Classes of Restriction for individual users or Call Handlers then you would want to set the CSS for the VM ports to the least restrictive policy for any user or Call Handler. From there, you would use different Restriction Tables and assignments within Unity to apply custom restrictions to users/call handlers as needed.
You are most correct my friend
If the CSS that is assigned to the VM Ports is set at
a "Restrictive" level then the Restriction Tables are not
in play. These Tables can however, be leveraged
in other scenarios to offer dialing to certain numbers at
a very granular level while restricting other numbers.
Whenever you are working with efforts to mitigate any
possible "Toll Fraud" make sure to try some calling patterns
(Local,LD,International) to ensure that your methods are