RFC 4366:Transport Layer Security (TLS) Extensions
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By the Client


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... "HostName" contains the fully qualified DNS hostname of the server, as understood by the client. The hostname is represented as a byte string using UTF-8 encoding [UTF8 ...


... unable to retrieve a certificate chain from the URL supplied by the client (see Section 3.3). This message MAY be fatal; for example, if client authentication is required by the server ...



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