Following the network giant, Microsoft and Mozilla, Apple on Wednesday announced that the latest operating system iOS 13 and macOS 10.15 (Catalina) also SHA-1 encryption algorithm is no longer supported. Apple released the latest iOS and web macOS requirements of the trust documents. All credentials certification authority (CA) TLS server certificates issued and must use the SHA-2 hash algorithm. Book release this fall of mobile and desktop operating system will no longer trust the signature SHA-1 certificates, which no longer support the use of HTTPS SHA-1 signature generator online. Not any upgrade to TLS server, the new iPhone and Mac computers SHA-2 when connecting these servers will appear online fail, app can not be performed, the page could not be loaded via Safari and other issues. 
This is the latest step in technology giants abandon SHA-1 algorithm. As early as 2017, the network giant will be associated with the implementation of collisions *** Dutch scholar, for the first time to crack SHA-1 calculation technology, proven safe before it is not enough, technology giants have already been released to suspend SHA-1 support program. Chrome and Mozilla Firefox Internet giant with effect from January 1, 2017 no longer in use, while Microsoft IE browser and Edge also in May 2017 to remove support for the SHA-1. Microsoft previously announced in July this year, Windows system will only support SHA-2 certificates, also requires that all older operating systems, including Windows 7 SP 1, Windows Server 2008 R2 SP1 / SP2 users must have the SHA-2 in July 2019 before support algorithms. It does not support the SHA-2 Windows system, in July this year after also not be able to download the update.
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