Bridge validator co-hosting
A cross-chain & bridge factor in the v1.7.0 rubric. Measured per protocol on a s cadence.
Methodology how we score #
**What this measures** This factor checks whether bridge validators share ASN (Autonomous System Number), data-centre operator, or cloud custodian — indicating that multiple validators could be taken offline or compromised by a single infrastructure event. Assessment combines bridge documentation with OSINT on validator operator infrastructure. This factor applies only to bridge-touching protocols; non-bridge protocols show this factor as N/A.
**Why it matters** Physical and infrastructure co-location transforms a nominally independent validator set into a correlated failure group. A 7-of-10 bridge with all validators hosted on the same AWS region effectively has a single infrastructure point of failure — a region outage or targeted attack against that provider can simultaneously compromise the quorum. The T-01 evidence base links co-hosting patterns to approximately 3 protocols in the hack database, including bridge incidents where signer-set compromise was facilitated by shared infrastructure. Harmony Bridge validators reportedly shared operational infrastructure that reduced the effective independence of its 2-of-5 threshold.
**Green / Yellow / Red** Green is scored when validators use diverse cloud providers, geographic regions, and independent node operators with documented independence. Yellow is scored when some validators share a cloud provider or region but no single provider controls a quorum. Red is scored when validators sharing a single provider or region constitute a quorum, or when all validators are operated by the same entity.
**Common gray cases** Gray is applied when validator infrastructure cannot be determined from public documentation and OSINT cannot confidently identify hosting relationships.
**Notable historical examples** No cross-hacked incidents are currently linked in the database for this factor.
Measurement what to look for #
Determine whether validators share ASN or data-center/custodian per on-chain and OSINT inference.