Allows users tracking the condition of the other telephone or the subscriber, for example, there will appear a signal on the screen of the telephone device informing that the subscriber is on the line and is temporarily unavailable.
SysMaster Corporation is the largest VoIP billing and call routing solution company in the world with the most VoIP business platform installations. Utilizing SysMaster equipment providers deliver high-quality calling solutions for more than 100 million c
Allows users tracking the condition of the other telephone or the subscriber, for example, there will appear a signal on the screen of the telephone device informing that the subscriber is on the line and is temporarily unavailable.
