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Export Grade Cryptography

What is export grade cryptography ? Since World War II, many countries including the U.S., U.K. and others, have regulated the export of cryptography in the interest of national security till 1992. Those countries used to believe that they had developed more advanced cryptographic solution than others and they wished to monitor the communication of other countries and hence restricted the advanced cryptographic solution to other nations, by their companies. Restriction had been eased down in 1992 and in 2000 but some are still there. Only those cryptography solutions which can be breaked by security agencies, were allowed to export and were known as Export Grade Cryptography. Ciphers itself are not of Export Grade as they properly follows algorithms. It is the use of cryptographic keys that are deliberately weekend so that security agencies can crack them as and when needed. The export-grade encryption had 512 bits, the maximum allowed under U.S. restrictions de

Server Name Indication (SNI)

TLS does not provide a mechanism for a client to tell a server the name of the server it is contacting. It may be desirable for clients to provide this information to facilitate secure connections to servers that host multiple 'virtual' servers at a single underlying network address. For taking care of this issue, SNI extension has been added into the TLS and published in RFC 6066 . Or to explain it in other words, Name-based virtual hosting allows multiple DNS hostnames to be hosted by a single server (usually a web server) on the same IP address. To achieve this the server uses a hostname presented by the client as part of the protocol (for HTTP the name is presented in the host header). However, when using HTTPS the TLS handshake happens before the server sees any HTTP headers. Therefore, it is not possible for the server to use the information in the HTTP host header to decide which certificate to present. SNI addresses this issue by having the client send the name of