Vouching architecture

• Twice a day, each server requests a current voucher from each CA and will use it for the next 24 hours

• Client picks two acceptable candidate Vouching Authorities (either by random or based on region)

• Clients request vouchers from servers as part of the SSL/TLS protocol handshake

• Server certificate and voucher: From different CAs

• Clients verify voucher signature and freshness

• Clients compare own network view with voucher information