Traffic engineering
146 Avaya Application Solutions IP Telephony Deployment Guide
Additional design criteria
●
Each site is to have a suitable number of PSTN trunks (which terminate on PNs in Atlanta
and Boston, and on the G350 Media Gateways in Cleveland).
●
This is a general business application (for example, no Call Center agents), where the
average usage per station is assumed to be 0.11 Erlangs, and the average call duration is
assumed to be 200 seconds.
●
Each site consists of a single Network Region, and all three Network Regions are
interconnected in the sense of the IRCM matrix.
●
One-third of all calls are intercom calls (that is, calls between two stations), one-third are
inbound PSTN trunk calls, and one-third are outbound PSTN trunk calls.
Preliminary calculations
Based on the assumption of 0.11 Erlangs per station,
Table 20: Example 1 station usage by
endpoint type
shows the total station usage for each station category in the system.
Call usage rates
In the previous section, station usages and overall endpoint usages, including both stations and
trunks, were discussed. The overall endpoint usage is sometimes referred to as port usage rate
(PUR). The term station usage rate (SUR) applies when referring only to the stations. In
general, a traffic usage rate, when expressed in Erlangs, represents the average number of
busy servers in a given server group. So, SUR represents the average number of stations in a
particular group that are simultaneously in use, while PUR represents the average number of
endpoints, including stations and trunks, in a particular group that are simultaneously in use.
Table 20: Example 1 station usage by endpoint type
Endpoints
Atlanta
(Erlangs)
Boston
(Erlangs)
Cleveland
(Erlangs)
DCP Telephones
60
20
IP Telephones
120
50
30
Analog stations
12
2
Road Warriors
3
Analog stations administered
to G350 Media Gateways
4
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 ...