Call usage rates
Issue 3.4.1 June 2005
157
First consider the 32 Erlangs of intercom CUR between Site 1 stations (
Table 24: Intercom COI
matrix for the Uniform Distribution model in Example 2: Uniform Distribution model
on
page 153). Site 1 (Atlanta) has a total of 1755 stations, 1107 of which are IP stations, and 648 of
which are circuit-switched stations. So, 63% of the stations in Site 1 are IP, and 37% are circuit
switched. Therefore, 63% of Site 1 intercom calls are generated by IP stations, and 63% of
those calls are terminated by IP stations. Since 63% of 63% is 39.7%, 39.7% of Site 1 intercom
calls are IP station to IP station. Similarly, 37% of the Site 1 intercom calls that are generated by
IP stations are terminated by circuit-switched stations. Since 37% of 63% is 23.3%, 23.3% of
Site 1 intercom calls are IP station to circuit-switched station.
Also, 37% of Site 1 intercom calls are generated by circuit-switched stations, and 63% of those
calls are terminated by IP stations. Since 63% of 37% is 23.3%, 23.3% of Site 1 intercom calls
are circuit-switched station to IP station. Finally, 37% of the Site 1 intercom calls that are
generated by circuit-switched stations are terminated by circuit-switched stations. Since 37% of
37% is 13.7%, 13.7% of Site 1 intercom calls are circuit-switched station to circuit-switched
station.
So, since 39.7% of Site 1 intercom calls are IP station to IP station, IP station to IP station call
usage is 39.7% of the 32 Erlangs of overall Site 1 intercom CUR, or 12.7 Erlangs. Similarly, both
the Site 1 IP station to circuit-switched station CUR and the Site 1 circuit-switched station to IP
station CUR are equal to 23.3% of 32 Erlangs, or 7.5 Erlangs. Finally, the Site 1 circuit-switched
station to circuit-switched station CUR is 13.7% of 32 Erlangs, or 4.4 Erlangs.
A similar process is used to break down the 12 Erlangs of intercom CUR into its components.
There are a total of 648 stations in Site 2 (Atlanta), 450 of which are IP stations, and 198 of
which are circuit-switched stations. So, 69% of the stations in Site 2 are IP, and 31% are
circuit-switched. We have already determined that 63% of intercom calls that are generated in
Site 1 are generated by IP stations. Similarly, 69% of intercom calls that are terminated in Site 2
are terminated by IP stations. Since 69% of 63% is 43.5%, 43.5% of Site 1 to Site 2 intercom
calls are IP station to IP station. Also, 31% of intercom calls that are terminated in Site 2 are
terminated by circuit-switched stations. Since 31% of 63% is 19.5%, 19.5% of Site 1 to Site 2
intercom calls are IP station to circuit-switched station.
Table 26: Endpoints in a three-site system
Endpoints
Atlanta
Boston
Cleveland
IP stations
1107
(1080 IP
Tele 27
Road Warriors)
450
(450 IP
Telephones)
270
(270 IP
Telephones)
Circuit-switched
stations
648
(540 DCP stations
+ 108 analog
stations)
198
(180 DCP stations
+ 18 analog
stations)
36
(36 analog stations)
PSTN trunks
120 (DS0) PSTN
Trunks
(5 T1 facilities)
48 (DS0) PSTN
Trunks
(2 T1 facilities)
24 (DS0) PSTN
Trunks
(1 T1 facility)
Summary of Contents for Application Solutions
Page 1: ...Avaya Application Solutions IP Telephony Deployment Guide 555 245 600 Issue 3 4 1 June 2005 ...
Page 20: ...About This Book 20 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 21: ...Issue 3 4 1 June 2005 21 Section 1 Avaya Application Solutions product guide ...
Page 22: ...22 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 106: ...Call processing 106 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 124: ...Avaya LAN switching products 124 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 139: ...Issue 3 4 1 June 2005 139 Section 2 Deploying IP Telephony ...
Page 140: ...140 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 186: ...Traffic engineering 186 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 204: ...Security 204 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 228: ...Avaya Integrated Management 228 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 274: ...Reliability and Recovery 274 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 275: ...Issue 3 4 1 June 2005 275 Section 3 Getting the IP network ready for telephony ...
Page 276: ...276 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 356: ...Network recovery 356 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 366: ...Network assessment offer 366 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 367: ...Issue 3 4 1 June 2005 367 Appendixes ...
Page 368: ...Appendixes 368 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 394: ...Access list 394 Avaya Application Solutions IP Telephony Deployment Guide ...
Page 414: ...DHCP TFTP 414 Avaya Application Solutions IP Telephony Deployment Guide ...