One of the primary advantages of VoIP over Telstra ISDN services is its scalability. Traditional ISDN systems often require businesses to purchase additional lines as they expand, leading to unnecessary expenses and logistical challenges. In contrast, VoIP systems can effortlessly accommodate growth, allowing organizations to add or remove users with ease. This scalability is particularly beneficial for businesses with fluctuating communication needs or those undergoing rapid expansion.Furthermore, VoIP offers a wealth of features and functionalities that are simply not possible with traditional ISDN services.