IP Telephony

Synonyms

Internet telephony

Definition

Internet telephony is the process of making telephone calls over the Internet.

Introduction

Internet telephony, also referred to as IP telephony (IPT), is the process of making telephone calls over the Internet, regardless of whether traditional telephones (POTS, GSM, ISDN, etc.), single use appliances, or audio-equipped personal computers are used in the calls. IPT is highly appealing for many reasons, the most important of which is the ease of implementing its services. Internet Telephony Service Providers (ITSP) can use a single IP-based infrastructure for providing traditional Internet, as well as Internet telephony access.

The Session Initiation Protocol (SIP)

The Session Initiation Protocol (SIP) is a signaling protocol for Internet Telephony. It is documented in (RFC3261, 2002) by the Internet Engineering Task Force (IETF), and is ideal for real-time multimedia communication signaling [1]. It is an end-to-end application layer signaling...