nd data on the links between the host and the customer. VoIP hosting providers include the manufacturers of IP PBXs listed above, as well as telephone companies and cable providers such as AT&T, Verizon, and Comcast Business. Communications Platform as a Service- Solutions for Communications Problems CPaaS companies develop software solutions related to voice telephony to often-complex communications issues. For example, Twilio, a communications software developer located in San Francisco, developed communications software that ride-hailing provider Uber uses for messaging and calls between its drivers and people that need rides. It additionally developed the messaging software used by Facebook's WhatsApp. www.TechnicalPDF.com Most CPaaS solutions are located in the cloud. Genband, Mitel, SAP, and Vonage with its acquisition of Nexmo are other CPaaS providers. Contact Centers-Efficiencies for Incoming and Outgoing Communications Contact centers are groups of agents that handle incoming customer service calls, text messages, chat, web queries, and outgoing sales, credit, and collections calls. Contact centers consist of software that is used to manage incoming and outgoing communications with agents, particularly when there are more calls, text messages, chat sessions, and e-mail than there are people to always respond to them immediately. Importantly, contact centers provide statistics on utilization of agents, telecommunications lines, and numbers of e-mail, text, and chat sessions. The main theory behind grouping agents into "pools" is that large groups of agents can handle more calls than the same number of agents organized into small groups, without overflow of calls between groups. This is analogous to the practice by the United States Post Office of using one long line for postal clerks rather than an individual line for each clerk. With one line for all postal workers, a clerk will be available more quickly from the pool and the same number of clerks will help more people within a given amount of time than