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S_TIME(1)                                          OpenSSL                                         S_TIME(1)

       s_time - SSL/TLS performance timing program

       openssl s_time [-connect host:port] [-www page] [-cert filename] [-key filename] [-CApath directory]
       [-CAfile filename] [-reuse] [-new] [-verify depth] [-nbio] [-time seconds] [-ssl2] [-ssl3] [-bugs]
       [-cipher cipherlist]

       The s_client command implements a generic SSL/TLS client which connects to a remote host using
       SSL/TLS. It can request a page from the server and includes the time to transfer the payload data in
       its timing measurements. It measures the number of connections within a given timeframe, the amount
       of data transferred (if any), and calculates the average time spent for one connection.

       -connect host:port
           This specifies the host and optional port to connect to.

       -www page
           This specifies the page to GET from the server. A value of '/' gets the index.htm[l] page. If
           this parameter is not specified, then s_time will only perform the handshake to establish SSL
           connections but not transfer any payload data.

       -cert certname
           The certificate to use, if one is requested by the server. The default is not to use a
           certificate. The file is in PEM format.

       -key keyfile
           The private key to use. If not specified then the certificate file will be used. The file is in
           PEM format.

       -verify depth
           The verify depth to use. This specifies the maximum length of the server certificate chain and
           turns on server certificate verification.  Currently the verify operation continues after errors
           so all the problems with a certificate chain can be seen. As a side effect the connection will
           never fail due to a server certificate verify failure.

       -CApath directory
           The directory to use for server certificate verification. This directory must be in "hash
           format", see verify for more information. These are also used when building the client
           certificate chain.

       -CAfile file
           A file containing trusted certificates to use during server authentication and to use when
           attempting to build the client certificate chain.

           performs the timing test using a new session ID for each connection.  If neither -new nor -reuse
           are specified, they are both on by default and executed in sequence.

           performs the timing test using the same session ID; this can be used as a test that session
           caching is working. If neither -new nor -reuse are specified, they are both on by default and
           executed in sequence.

           turns on non-blocking I/O.

       -ssl2, -ssl3
           these options disable the use of certain SSL or TLS protocols. By default the initial handshake
           uses a method which should be compatible with all servers and permit them to use SSL v3, SSL v2
           or TLS as appropriate.  The timing program is not as rich in options to turn protocols on and off
           as the s_client(1) program and may not connect to all servers.

           Unfortunately there are a lot of ancient and broken servers in use which cannot handle this
           technique and will fail to connect. Some servers only work if TLS is turned off with the -ssl3
           option; others will only support SSL v2 and may need the -ssl2 option.

           there are several known bug in SSL and TLS implementations. Adding this option enables various

       -cipher cipherlist
           this allows the cipher list sent by the client to be modified. Although the server determines
           which cipher suite is used it should take the first supported cipher in the list sent by the
           client.  See the ciphers(1) command for more information.

       -time length
           specifies how long (in seconds) s_time should establish connections and optionally transfer
           payload data from a server. Server and client performance and the link speed determine how many
           connections s_time can establish.

       s_client can be used to measure the performance of an SSL connection.  To connect to an SSL HTTP
       server and get the default page the command

        openssl s_time -connect servername:443 -www / -CApath yourdir -CAfile yourfile.pem -cipher commoncipher [-ssl3]

       would typically be used (https uses port 443). 'commoncipher' is a cipher to which both client and
       server can agree, see the ciphers(1) command for details.

       If the handshake fails then there are several possible causes, if it is nothing obvious like no
       client certificate then the -bugs, -ssl2, -ssl3 options can be tried in case it is a buggy server. In
       particular you should play with these options before submitting a bug report to an OpenSSL mailing

       A frequent problem when attempting to get client certificates working is that a web client complains
       it has no certificates or gives an empty list to choose from. This is normally because the server is
       not sending the clients certificate authority in its "acceptable CA list" when it requests a
       certificate. By using s_client(1) the CA list can be viewed and checked. However some servers only
       request client authentication after a specific URL is requested. To obtain the list in this case it
       is necessary to use the -prexit option of s_client(1) and send an HTTP request for an appropriate

       If a certificate is specified on the command line using the -cert option it will not be used unless
       the server specifically requests a client certificate. Therefor merely including a client certificate
       on the command line is no guarantee that the certificate works.

       Because this program does not have all the options of the s_client(1) program to turn protocols on
       and off, you may not be able to measure the performance of all protocols with all servers.

       The -verify option should really exit if the server verification fails.

       s_client(1), s_server(1), ciphers(1)

50                                               2013-03-05                                        S_TIME(1)

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