mirror of
https://github.com/logos-blockchain/research.git
synced 2026-08-09 04:33:15 +00:00
64 lines
2.9 KiB
Python
64 lines
2.9 KiB
Python
|
"""Protocol constants and epoch/window geometry.
|
|||
|
|
|
|||
|
|
All slot geometry derives from the pair ``(k, f)`` so a scaled-down ``k`` (used for
|
|||
|
|
parameter sweeps) automatically shrinks the epoch and measurement window. See
|
|||
|
|
``cryptarchia-v1-protocol.md`` and ``cryptarchia-total-stake-inference.md``.
|
|||
|
|
"""
|
|||
|
|
|
|||
|
|
from __future__ import annotations
|
|||
|
|
|
|||
|
|
# --- True protocol values (full scale) -------------------------------------
|
|||
|
|
K_TRUE = 2160 # security parameter (blocks)
|
|||
|
|
F = 1.0 / 30.0 # slot activation coefficient (default; configurable per run)
|
|||
|
|
W_DEFAULT = 300 # uncle reference window w_u (slots)
|
|||
|
|
BETA_DEFAULT = 1.0 # TSI learning rate
|
|||
|
|
SLOT_SECONDS = 1 # slot length (seconds) — so 1 slot == 1 s
|
|||
|
|
|
|||
|
|
|
|||
|
|
# --- Real-world inter-node network latency (per gossip link) ---------------
|
|||
|
|
# A slot is SLOT_SECONDS = 1 s, so measured internet latencies (tens–hundreds of ms) are
|
|||
|
|
# FRACTIONS of a slot. The values below are one-way, application-level latencies between two
|
|||
|
|
# directly-peered nodes, bucketed by the geographic relationship of the peers — in a globally
|
|||
|
|
# distributed node set a random peer is usually on another continent. (≈ RTT/2 from public
|
|||
|
|
# latency measurements plus a little gossip processing/serialization overhead.) A block
|
|||
|
|
# gossip-floods over the peering graph, so its end-to-end delay to a far node is the sum of
|
|||
|
|
# a few such per-link latencies along the fastest path (Dijkstra) — see topology.py.
|
|||
|
|
GEO_LATENCY_BANDS_SLOTS = (
|
|||
|
|
0.015, # metro / same country (~15 ms one-way)
|
|||
|
|
0.040, # same continent, e.g. EU↔EU (~40 ms)
|
|||
|
|
0.090, # transatlantic, e.g. EU↔US-East (~90 ms)
|
|||
|
|
0.200, # antipodal, e.g. EU↔AU / EU↔JP (~200 ms)
|
|||
|
|
)
|
|||
|
|
# Share of random peer links falling in each band for a globally distributed node set
|
|||
|
|
# (NA/EU/Asia-weighted). Most peer pairs are cross-continent, hence the long-latency mass.
|
|||
|
|
GEO_LATENCY_WEIGHTS = (0.15, 0.35, 0.35, 0.15)
|
|||
|
|
# Mean one-way latency of a random global peer link under the mixture above (~0.078 slot,
|
|||
|
|
# i.e. ~78 ms). Used to rescale the "geo" link-latency distribution to a requested mean.
|
|||
|
|
GEO_LATENCY_MEAN_SLOTS = sum(
|
|||
|
|
b * w for b, w in zip(GEO_LATENCY_BANDS_SLOTS, GEO_LATENCY_WEIGHTS, strict=True)
|
|||
|
|
)
|
|||
|
|
|
|||
|
|
|
|||
|
|
def floor_k_over_f(k: int, f: float = F) -> int:
|
|||
|
|
"""``floor(k / f)`` — the base quantum of the epoch schedule."""
|
|||
|
|
return int(k / f)
|
|||
|
|
|
|||
|
|
|
|||
|
|
def epoch_len(k: int, f: float = F) -> int:
|
|||
|
|
"""Epoch length in slots: ``10 * floor(k/f)``."""
|
|||
|
|
return 10 * floor_k_over_f(k, f)
|
|||
|
|
|
|||
|
|
|
|||
|
|
def period_T(k: int, f: float = F) -> int:
|
|||
|
|
"""TSI measurement window length ``T`` in slots: ``6 * floor(k/f)``.
|
|||
|
|
|
|||
|
|
This is the first ``6*floor(k/f)`` slots of the (previous) epoch over which the
|
|||
|
|
block density is measured.
|
|||
|
|
"""
|
|||
|
|
return 6 * floor_k_over_f(k, f)
|
|||
|
|
|
|||
|
|
|
|||
|
|
def expected_blocks_in_window(k: int, f: float = F) -> float:
|
|||
|
|
"""Expected honest-chain block count in the measurement window at equilibrium."""
|
|||
|
|
return period_T(k, f) * f
|