Ключевые слова: background, business, button, cable, call, center, communication, communications, computer, conference, connection, contact, corporate, customer, digital, display, distance, element, equipment, global, headphone, headset, industry, internet, ip, keypad, landline, microphone, net, network, object, office, operator, over, phone, phones, protocol, receiver, screen, service, support, talking, tech, technical, technology, telemarketing, telephone, telephony, voice, voip,