可复用Garbling的注解

Notes on Reusable Garbling

Garbling是一个有着多重应用的密码原语,主要适用于权力受限的场景,比如安全多方计算(MPC)、属性加密(ABE)、函数加密(FE)、不可区分混淆(IO)等等.2013年以前的garbling方案都是一次性garbling,GKP+13和Agr17提出了可复用garbling.我们曾经指出,可复用garbling并没有获得新的应用场景,它仍然是一个一次性garbling.本文继续讨论可复用garbling的可用性和效率.本文指出以下两点:(1)即使可复用garbling被当作一次性garbling使用,也常常是不可用的,它只能用于两个基本场景中的基本场景二,不能用于基本场景一.比如,它不能用于安全多方计算(MPC).(2)即使可复用garbling被当作一次性garbling用于基本场景二,没有证据表明它比原来的一次性garbling效率更高.

Garbling is a cryptographic primitive with multiple applications.It is often used in scenarios where the authority is limited,e.g.,secure multiparty computation,attribute-based encryption,functional encryption,indistinguishable obfuscation,etc.All garbling schemes proposed before 2013 are one-time garbling.GKP+13 and Agr17 propose reusable garbling.The authors once pointed out that reusable garbling does not acquire new application scenarios,which means that it is still one-time garbling.This paper further discusses the validity of reusable garbling,which is concluded by the following two points.(1)Even if reusable garbling is used as one-time garbling,it is often invalid.Reusable garbling can only be applied in the second fundamental scenario out of two fundamental scenarios,and cannot be applied in the first fundamental scenario.E.g.,it cannot be applied in secure multiparty computation.(2)Even if reusable garbling is applied in the second fundamental scenario,there is no proof that it is more efficient than the previous one-time garbling.