For a DHS SBIR Phase I award, VOCAL (Verification of Caller Ascertained Logically), AnaVation built a prototype of the Do Not Spoof Service (DNSS), a modular, componentized solution for spoofed call detection and blocking and/or notification via multi-layered call and user authentication and validation. During Phase II we will focus on production-level development, such as improving and adding functionality, hardening code, refreshing the User Interface (UI) and User Experience (UX), testing and QA. This will result in delivering a production-ready minimum viable product (MVP) capable of deployment. The DNSS MVP will include five componentized services that will integrate across both mobile and VoIP systems and leverage applicable and operational best practices for the telephony industry to address multiple telephony spoofing challenges identified in Phase I research. The solution delivered at the end of Phase II will minimize the financial and security impact of spoofed calls.Our modified technical approach - as opposed to that of a single, take-all-or-nothing solution - will amplify DNSS's value and increase its commercial viability, and, most importantly, its impact in combating malicious spoofed calls. There are commercial applications for government organizations, telecommunications providers, industry organizations and caller-ID/call-blocking solutions providers. AnaVation has already received a Letter of Intent (LOI) from Nomorobo, one of the largest call-blocking services, indicating that it intends to integrate/consume one of DNSS's services once production-ready (Do Not Originate as a Service (DNOaaS)).