Avaya 555-245-600 manual Relationship Between Processing Occupancy and Bhcc Rate

Traffic engineering

occupancy is allocated on an as-needed basis, such as for periodic maintenance functions. However, if the overall server occupancy exceeds a particular threshold, SM operations are postponed until a quieter traffic period.

Usually, the relationship between the sum of static and CP occupancy, as a function of BHCC, is linear, with a positive y-intercept, as illustrated in Figure 69: Relationship Between Processing Occupancy and BHCC Rate on page 212. The slope of the line corresponds to the average processing cost per call, and the intercept corresponds to the idle (that is, no-load) occupancy. The average processing cost per call depends on the mix of calls that is being handled by the system, and how complex each type of call is. For general business calls, nearly all of the CP occupancy is associated with setting up and tearing down calls. The call processing that is required for maintaining the call once it has been established is negligible in comparison, regardless of how long the call lasts. In a call center, the additional cost of processing vectoring steps throughout the lifetime of a call must also be considered.

Figure 69: Relationship Between Processing Occupancy and BHCC Rate

Processing Occupancy (CP + Static)

Idle (No-Load)

Occupancy

BHCC Rate

To determine the anticipated processor occupancy that is associated with a particular configuration, the average processing cost per call must be determined based on the anticipated volume of each type of call, and the complexity of the various call types. This average cost per call implies the slope of the line in relating static and CP occupancy to the BHCC rate. The intercept of that line, which corresponds to the no-load occupancy, depends on several factors, including which Communication Manager platform is being used, how many endpoints are administered, and so on.

Communication Manager systems are designed to keep the sum of static and CP occupancy below a particular threshold. This is done to allow a suitable amount of processing time for system management functions.

So for a given configuration, the various types of calls to be supported are identified, and the processing cost for each call type (based upon the complexity of the call) must be assessed. That information can then be used to determine the average processing cost per call, based on the anticipated relative frequencies of the various call types. The slope of the line relating the sum of static and CP occupancy can then be determined from the average processing cost per call. The intercept of that line is determined by information such as the Communication Manager platform used, the number of endpoints administered, and so on.

212 Avaya Application Solutions IP Telephony Deployment Guide