Which solution offers a more economical option than regular long-distance service for routing telephone calls over a data network?

The most economical option for routing telephone calls over a data network is VoIP services. VoIP, or Voice over Internet Protocol, allows voice communication to be transmitted over the internet or other IP-based networks. This technology leverages existing data network infrastructure, enabling significant cost savings compared to traditional long-distance services. VoIP services can reduce costs by avoiding the fees associated with circuit-switched telephony, allowing users to make calls over more affordable broadband connections.

Packet telephony is closely related to VoIP but does not necessarily imply the same breadth of application and compatibility with existing internet infrastructure. While packet telephony also handles voice in packet format, it typically requires specific setups and considerations. Therefore, VoIP is the more recognized and widely adopted solution among the options available, suitable for businesses and individuals looking to optimize their communication expenses efficiently.

On the other hand, DSS1 signaling and ISDN connections relate more to the structure and protocols involved in traditional telephony systems rather than offering a data-driven, cost-effective approach to voice communication over the internet. These technologies are generally more expensive and less flexible compared to using VoIP solutions.