GAL-2 Operational Source Isolation Demonstration: A General-Purpose Mac Client Adopting a GAL-2-Corrected Local SNTP Feed

This evidence package documents a controlled two-Mac operational source isolation demonstration using GAL-2. A Bridge Mac ran the August 2025 pre-AWS protected local GAL-2 core and served an SNTP-compatible local time feed derived from GAL-2-corrected time. A Client Mac was configured to use the Bridge Mac as its macOS Network Time source instead of Apple public time. After reconfiguration, read-only SNTP diagnostics showed that the Client Mac system clock aligned near the GAL-2 Bridge while Apple public time remained approximately 11 seconds ahead of the Client Mac. A 30-minute adoption monitor sampled both Apple public time and the GAL-2 Bridge every 5 minutes. Across 6/6 paired samples, the Client Mac remained aligned near the GAL-2 Bridge and not near Apple public time. Primary claim: A general-purpose Mac client adopted a local GAL-2-corrected SNTP feed as its macOS Network Time source instead of directly consuming Apple public time. Key results: - Bridge Mac IP: 192.168.14.171- Client Mac IP: 192.168.14.174- Client Mac was changed from time.apple.com to 192.168.14.171- Bridge served SNTP-compatible responses derived from GAL-2 local core output- Observed GAL-2 correction: gal2_corrected = epoch - 11 seconds- Client system clock aligned near the GAL-2 Bridge- Apple public time remained approximately 11.0 to 11.2 seconds ahead of the Client Mac- 30-minute adoption monitor result: PASS- 6/6 paired samples aligned near GAL-2 Bridge- 0/6 paired samples aligned near Apple public time Boundary: This demonstration does not claim physical oscillator control. This demonstration does not claim metrological replacement of UTC. This demonstration does not claim that the observed -11 second correction is universally correct. This demonstration does not claim production readiness, enterprise scale, or compatibility with all absolute-time-sensitive systems. This demonstration supports operational source isolation and sustained adoption of a GAL-2-corrected local SNTP feed by a general-purpose Mac client. Final master archive SHA256: 4f3ccc944cc909a1e1a8af58f4118406d9939e44f256d4a07fec5ef3b6af291b Project website: https://gal-2.com This record is published for research evidence, timestamping, citation, and technical review. Publication of this evidence package does not grant rights to reproduce, commercialize, reverse engineer, derive, sublicense, or implement GAL-2 core technology, protected formulas, trade secrets, trademarks, or proprietary system architecture.