This is a Voice over Internet Protocol (VoIP) and streaming media service based on the Session Initiation Protocol (SIP) by which Internet telephony service providers (ITSPs) deliver telephone services and unified communications to customers equipped with SIP-based private branch exchange (IP-PBX) and Unified Communications facilities
ShoreTel Sky is the modern phone system for today’s agile, mobile and always-on company. While other cloud-communications companies have added business VoIP services as an afterthought, hosted VoIP is the heart of ShoreTel Sky.