Setting the maximum protocol version
        is mainly useful for testing or if some component has issues working
        with a newer protocol.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="libpq-connect-krbsrvname" xreflabel="krbsrvname">
      <term><literal>krbsrvname</literal></term>
      <listitem>
       <para>
        Kerberos service name to use when authenticating with GSSAPI.
        This must match the service name specified in the server
        configuration for Kerberos authentication to succeed. (See also
        <xref linkend="gssapi-auth"/>.)
        The default value is normally <literal>postgres</literal>,
        but that can be changed when
        building <productname>PostgreSQL</productname> via
        the <option>--with-krb-srvnam</option> option
        of <application>configure</application>.
        In most environments, this parameter never needs to be changed.
        Some Kerberos implementations might require a different service name,
        such as Microsoft Active Directory which requires the service name
        to be in upper case (<literal>POSTGRES</literal>).
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="libpq-connect-gsslib" xreflabel="gsslib">
      <term><literal>gsslib</literal></term>
      <listitem>
       <para>
        GSS library to use for GSSAPI authentication.
        Currently this is disregarded except on Windows builds that include
        both GSSAPI and SSPI support.  In that case, set
        this to <literal>gssapi</literal> to cause libpq to use the GSSAPI
        library for authentication instead of the default SSPI.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="libpq-connect-gssdelegation" xreflabel="gssdelegation">
      <term><literal>gssdelegation</literal></term>
      <listitem>
       <para>
        Forward (delegate) GSS credentials to the server.  The default is
        <literal>0</literal> which means credentials will not be forwarded
        to the server.  Set this to <literal>1</literal> to have credentials
        forwarded when possible.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="libpq-connect-scram-client-key" xreflabel="scram_client_key">
      <term><literal>scram_client_key</literal></term>
      <listitem>
       <para>
        The base64-encoded SCRAM client key.  This can be used by foreign-data
        wrappers or similar middleware to enable pass-through SCRAM
        authentication. See <xref
        linkend="postgres-fdw-options-connection-management"/> for one such
        implementation.  It is not meant to be specified directly by users or
        client applications.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="libpq-connect-scram-server-key" xreflabel="scram_server_key">
      <term><literal>scram_server_key</literal></term>
      <listitem>
       <para>
        The base64-encoded SCRAM server key.  This can be used by foreign-data
        wrappers or similar middleware to enable pass-through SCRAM
        authentication. See <xref
        linkend="postgres-fdw-options-connection-management"/> for one such
        implementation.  It is not meant to be specified directly by users or
        client applications.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="libpq-connect-service" xreflabel="service">
      <term><literal>service</literal></term>
      <listitem>
       <para>
        Service name to use for additional parameters.  It specifies a service
        name in <filename>pg_service.conf</filename> that holds additional connection parameters.
        This allows applications to specify only a service name so connection parameters
        can be centrally maintained. See <xref linkend="libpq-pgservice"/>.
       </para>
      </listitem>
     </varlistentry>

     <varlistentry id="libpq-connect-target-session-attrs" xreflabel="target_session_attrs">