Problem Description : AC client takes a very long time for call control to come up. This is usually seen over WAN links.
Symptoms : CUCM Version : Any AC Client : Any Number of Call Parks - Huge Number Call Park Range 1xx means 100 Call Park Numbers
While querying CTI for the Monitored DNs, CTI responds with 100 DNs at a time, thus there are Z such request/responses, where Z = Total Number Of Call Park/100. After that we have about Zx100 LineOpenRequests. This operation is taking up the time. Unless all the parked lines are opened, call control cannot come up. Depending on network connectivity this time can vary. If you are on the LAN then it will take lesser time than if you were over a WAN.
This is the way how AC is designed. The design logic behind AC client to monitor all the parked lines before call control can come up is considering the fact that an attendant who is already logged in has parked a call and when a new attendant logs in, as soon as its call control comes up, the parked call can be shown in the park window of the newly logged in attendant.
