Lucent Technologies Release 8.2 manual ExampleInternet Call Center, Problem, Solution

D Capacities and Performance

Number of C-LANsThe number of C-LAN circuit packs needed can be estimated as follows: needed

1Calculate the C-LAN socket carried load, for c sockets, CLc

2The number of C-LANs needed is:

#C-LANS = CLc/448 for infinite source, GOS of P001

#C-LANS = CLc/508 for “full availability.”

Assumptions

This formula assumes:

•508 is the maximum number of simultaneous TCP/UDP connections per C-LAN.

•448 is the average of Erlang B and Erlang C for GOS = P001 and 508 connections.

ExampleInternet Call Center

A DEFINITY call center with all incoming connections originating as H.323 DID endpoints on the Internet. The customer requires 10,000 Busy Hour Calls (BHCs) be carried, with a GOS of P001. The average call holding time is 100 seconds and the codec is G723.1.

Problem

Calculate the DEFINITY resources required — the number of C-LANs and the number of MedPros.

Solution

The average number of C-LAN sockets per call (c), for H.323 endpoints, is 2.

The number of audio streams per MedPro (a), for the G723.1 codec, is 22.

The endpoint carried load is:

10,000(calls) x 1(CCS holding time per call)/36(CCS per Erlang) = 277.8 Erlangs.

From the MedPro table, 15 MedPro boards are required (rounding up).

Since there are 2 sockets per call (for H.323 endpoints), the socket carried load is 2x277.8 = 555.6 Erlangs.

Using the C-LAN formula, 555.6/448 = 2 C-LAN boards are required (rounding up).

		Administration for Network Connectivity
412	CID: 77730	555-233-504 — Issue 1 — April 2000