Number Portability Databases (NPDB) play a pivotal role in modern telecommunications by facilitating the seamless transfer of phone numbers between service providers. However, traditional NPDB systems face significant challenges, including centralization, high costs, and security vulnerabilities. This paper proposes a novel approach leveraging blockchain technology through the ENUMER system. ENUMER, designed initially to enhance ENUM operations, demonstrates a unique suitability for NPDB tasks due to its decentralized architecture, enhanced security, and cost efficiency. Our study involved testing ENUMER on standard hardware to ensure results stem from architectural advantages rather than high-performance equipment. The findings reveal sub-millisecond retrieval times and rapid record updates, showcasing ENUMER’s potential to outperform traditional NPDB systems. Although direct comparison data from existing NPDBs is scarce, our results suggest that ENUMER can serve as both an immediate solution and a foundation for future NPDB developments. For example, integrating public key infrastructure for caller ID verification could further enhance its functionality. This research highlights ENUMER’s capability to address current NPDB limitations and offers a promising direction for future improvements in telecom infrastructure.

This paper presents a method for mitigating unwanted communications such as spam, robocalls, and DoS attacks, proposing a proactive approach based on creating financial accountability for message originators through electronic postage stamps utilizing blockchain technology. The concept involves each email or message being accompanied by an unpublished blockchain transaction that destroys a small amount of the originator’s coins, termed an ”electronic postage stamp.” If a message is deemed unwanted, the recipient can publish the stamp transaction on the blockchain, leading to the destruction of associated coins and penalizing the originator. The SpamBat system, an MVP (Minimum Viable Product) implementation of this method, is introduced, detailing the processes for generating, transmitting, and redeeming these stamps. The paper also explores potential application areas across email, telephony, and network traffic, emphasizing the system’s independence from any organizational entity or centralized services, enhancing its resilience and reliability compared to current network service-based solutions. Limitations and challenges in implementation are discussed, alongside prospects for further development and enhancement within the context of modern digital security and data protection requirements. Thus, SpamBat represents a significant advancement in securing users against various forms of digital intrusion.