In a non-Call-By-Call Service Selection environment, a trunk group must be preassigned and provisioned for each desired service (for example, MEGACOM telecommunications service, WATS, SDN, and so on). With this arrangement, each trunk group must be designed to accommodate the peak traffic load for the intended service application. Furthermore, the time when one service application encounters peak traffic may not coincide with when another service application encounters peak traffic. As an alternative, if multiple network services are accommodated with a single trunk group (referred to as a CBC Trunk Group), and that trunk group is provided with allocation and scheduling controls, significant trunking efficiencies may be realized by distributing the total traffic for all of the specified network services over the total number of available trunk members.

By implementing Usage Allocation Plans (UAPs) you can optimize, within certain limits, the CBC trunk group without involving any of the Inter-Exchange Carrier/Local Exchange Carrier (IXC/LEC) network services personnel. Each Usage Allocation Plan specifies the network services/features that may be accommodated with the trunk group. It also specifies the minimum number of reserved channels and maximum number of channels each service/feature may use at a given time.

The free pool concept is associated with UAP’s. Specifically, free pool refers to the number of trunks not reserved for a specific service/feature and free to be assigned to another service or feature. The free pool is calculated as:

Each UAP may be administered as fixed or scheduled. If fixed, a specified plan remains in effect continuously. If scheduled, two or three UAPs may be scheduled to vary both by day of week and time of day.

Before you analyze the Trunk Group CBC Measurements Report, you must know the intent of the strategy for each UAP. You should have (in hand) a completed copy of the CBC Trunk Group UAP and the associated Assignment Schedule, which are Pages 3 and 4 of the Trunk Group Administration screen. For more information, see Avaya Aura® Communication Manager Screen Reference.

For wideband calls that consume more than 64 kbps of bandwidth, the total usage consumed is reflected in the Total Usage field. (For example, the usage for a 384-kbps call is six times more than for a 64-kbps call.) However, these calls are counted only as a single call. The call counts that may be incremented due to wideband calls are: Total Seize, Incoming Seize, Overflow Trunk Group, Overflow Service/Feature, and Overflow Maximum Service/Feature. The %ATB and %Out Blk fields are also affected by wideband calls.