Avaya 555-245-600 manual Number of type t stations in Site

Call usage rates

The general formula that is used to determine the expanded intercom CUR entries in Table 31 is:

CUR generated by stations of type t in Site i	= fi t ⋅ fj t ⋅ (intercom CUR from Site i to Site j )
and terminated by stations of type t in Site j

where:

● “Type t” refers to IP or circuit-switched

	t		number of type t stations in Site i
●	fi	=	---------------------------------------------------------------------------------total number of stations in Site i
	t		number of type t stations in Site j
●	fj	=	---------------------------------------------------------------------------------total number of stations in Site j

Now that the intercom CURs have been determined, CURs that involve trunks will be addressed. First, because Communication Manager systems are rarely used to route PSTN traffic, all of the COI matrix entries that correspond to PSTN-PSTN traffic are zero. Next, Table 26 and Table 27 help us determine the entries that correspond to inbound and outbound PSTN traffic.

According to Table 26, the inbound PSTN usage that arrives on Site 1 trunks and terminates at Site 1 stations is 49 Erlangs. We have already determined that 63% of the stations in Site 1 are IP and 37% are circuit switched. Therefore, the Uniform Distribution model implies that 63% of the 49 Erlangs (that is, 30.9 Erlangs) is inbound to Site 1 IP stations, and 37% of the 49 Erlangs (that is, 18.1 Erlangs) is inbound to Site 1 circuit-switched stations. Similarly, the Uniform Distribution model and Table 27 together imply that 63% of the 49 Erlangs of Site 1 outbound PSTN usage (that is, 30.9 Erlangs) is outbound from Site 1 IP stations through Site 1 PSTN trunks, and 37% (that is, 18.1 Erlangs) is outbound from Site 1 circuit-switched stations through Site 1 PSTN trunks. Note that by an assumption in Example 2: Uniform Distribution model, Site 1 inbound and outbound traffic only terminates and originates at Site 1 stations. This completes the work for Site 1. Sites 2 and 3 are handled in a similar manner, and the resulting completed COI matrix for Example 4: Expanded COI matrices is provided in Table 32: Completed COI matrix for Example 4: Expanded COI matrices on page 196.

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