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How to Cheat at VoIP Security by Michael Gough, CISSP Thomas Porter CCNP, CCDA, CCS

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Chapter 2

The Hardware Infrastructure

Solutions in this chapter:

Introduction

Even after the introduction of VoIP, business telephony equipment has remained focused on two areas: (1) reducing the cost of Public Switched Telephone Network (PSTN) connectivity overall and (2) adding business communications feature-functionality. Since the first private branch exchange (PBX) was introduced in 1879, business customers have sought cost savings by reducing the number of physical lines or trunks that interconnect with the PSTN. Because most calls in a large organization remain within it, cost and security benefits accrue immediately by placing a telephone switch inside the organization. ...

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