SSM-Clock Stamp – Worked Example (7.2)

Goal. A complete, by-hand construction of a single stamp line — all plain ASCII, deterministic, and ready to audit.

Inputs

  • UTC timestamp: iso_utc = "2025-10-13T10:53:57Z"
  • File bytes (ASCII): the 6-byte string hello\n

Step 1 — UTC to epoch seconds

  • Compute unix_seconds = seconds_since_1970_UTC(iso_utc) = 1760352837

Step 2 — Deterministic clock from UTC

  • Angle primitives:
    wrap360(x) = x - 360*floor(x/360)
  • Raw angle: (unix_seconds / 86400) * 360 = 163.48749999981374 + 360*k
  • Normalize: theta_deg = 163.48749999981374
  • Canonical print (binary64, half-even), default theta_prec = 5:
    theta_str = "163.48750"
  • Discrete sector: rasi_idx = floor(theta_deg / 30) = 5

Step 3 — File content hash

  • Select file algorithm (default): algo = sha256
  • Digest over exact bytes (streaming allowed):
    h_file = sha256(file_bytes)
  • For hello\n (68 65 6c 6c 6f 0a):
    h_str = "5891b5b522d5df086d0ff0b110fbd9d21bb4fc7163af34d08286a2e846f6be03"

Step 4 — Build the stamp core (ASCII, no spaces)

  • stamp_core = "SSMCLOCK1|" + iso_utc + "|" + rasi_idx + "|" + theta_str + "|" + h_str
  • Result:
    SSMCLOCK1|2025-10-13T10:53:57Z|5|163.48750|5891b5b522d5df086d0ff0b110fbd9d21bb4fc7163af34d08286a2e846f6be03

Step 5 — Append-only chain (first record)

  • Chain seed: chain_0 = "0"*64
  • Chain algorithm (default): chain_algo = sha256
  • Recurrence: chain_1 = sha256( ascii(chain_0 + "|" + stamp_core) )
  • Result:
    chain_str = "e5243368aaaf8168f02927dd69e02276bce15aa96e261d17bae5ba0e8d315801"

Step 6 — Final stamp line (emit one ASCII line)

  • Base form:
    SSMCLOCK1|2025-10-13T10:53:57Z|5|163.48750|5891b5b522d5df086d0ff0b110fbd9d21bb4fc7163af34d08286a2e846f6be03|e5243368aaaf8168f02927dd69e02276bce15aa96e261d17bae5ba0e8d315801
  • Optional tail (illustrative; non-breaking):
    SSMCLOCK1|2025-10-13T10:53:57Z|5|163.48750|5891b5b5...6be03|e5243368...15801|kv:algo=sha256;chain_algo=sha256;theta_prec=5;float=ieee75464;time_mode=derived_utc

Quick verification (by hand)

  • Hash check: recompute h' = sha256(file_bytes) → must equal h_str.
  • Clock check: recompute from iso_utc; require rasi'_idx = 5 and theta_str' = "163.48750".
  • Chain check (first row): with chain_0 = "0"*64, recompute sha256( ascii(chain_0 "|" stamp_core) ) → must equal chain_str.

Tiny variant (for contrast)

  • If the file were hello (no newline), the digest field would be:
    sha256("hello") = 2cf24dba5fb0a30e26e83b2ac5b9e29e1b161e5c1fa7425e73043362938b9824
    (All other steps unchanged if iso_utc stays the same.)

Navigation
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