Abstract decentralized calling using VOIP

Аннотация

People in urban areas often use landline telephone services to make phone calls. These services are based on a Public Switched Telephone Network (PSTN). PSTN phone numbers are not mobile; a person cannot have the same telephone number when they move to a new location. This thesis describes a solution that addresses the limitation of non-mobile phone numbers and expensive long distance calling that exists in PSTNs using Voice Over Internet Protocol (VoIP). The solution presented in this paper demonstrates the integration of Session Initiation Protocol (SIP) with other available systems. This solution is available as a service that will be hosted on a residential router, which maintains its connection to the Internet and is implemented using Freeswitch soft-switch on a Pfsense router. This thesis covers calling scenarios between SIP and SIP-PSTN users. It will also discuss the various protocols involved in routing a call.