diff --git a/wsmancmd.py b/wsmancmd.py
index 323a204..e40861d 100755
--- a/wsmancmd.py
+++ b/wsmancmd.py
@@ -20,52 +20,110 @@
 
 from winrm import protocol
 
+AUTH_BASIC = "basic"
+AUTH_KERBEROS = "kerberos"
+AUTH_CERTIFICATE = "certificate"
+
+DEFAULT_PORT_HTTP = 5985
+DEFAULT_PORT_HTTPS = 5986
+
+CODEPAGE_UTF8 = 65001
 
 def print_usage():
-    print ("%s -U <url> -u <username> -p <password> <cmd> [cmd_args]" %
-           sys.argv[0])
+    print ("%s [-U <url>] [-H <host>] [-P <port>] [-s] "
+           "[-a <basic|kerberos|certificate>] "
+           "[-u <username>] [-p <password>] "
+           "[-c <client_cert_pem> -k <client_cert_cert_key_pem>] "
+           "<cmd> [cmd_args]" % sys.argv[0])
 
 
 def parse_args():
-
+    args_ok = False
+    auth = AUTH_BASIC
     username = None
     password = None
     url = None
+    host = None
+    port = None
+    use_ssl = False
     cmd = None
+    cert_pem = None
+    cert_key_pem = None
+    server_cert_validation = 'validate'
+    is_powershell_cmd = False
 
     try:
         show_usage = False
-        opts, args = getopt.getopt(sys.argv[1:], "hU:u:p:c:")
+        opts, args = getopt.getopt(sys.argv[1:], "hsU:H:P:u:p:c:k:v:a:",
+                                   "powershell")
         for opt, arg in opts:
             if opt == "-h":
                 show_usage = True
+            if opt == "-s":
+                use_ssl = True
+            if opt == "-H":
+                host = arg
+            if opt == "-P":
+                port = arg
             if opt == "-U":
                 url = arg
+            elif opt == "-a":
+                auth = arg
             elif opt == "-u":
                 username = arg
             elif opt == "-p":
                 password = arg
+            elif opt == "-c":
+                cert_pem = arg
+            elif opt == "-k":
+                cert_key_pem = arg
+            elif opt == "-v":
+                server_cert_validation = arg
+            elif opt == "--powershell":
+                is_powershell_cmd = True
 
         cmd = args
 
-        if show_usage or not (url and username and password and cmd):
+        if (show_usage or not
+                (cmd and
+                 (url and not host and not port and not use_ssl) or
+                  host and ((bool(port) ^ bool(use_ssl) or
+                            not port and not use_ssl)) and
+                 (auth == AUTH_BASIC and username and password or
+                  auth == AUTH_CERTIFICATE and cert_pem and cert_key_pem or
+                  auth == AUTH_KERBEROS))):
             print_usage()
+        else:
+            args_ok = True
 
     except getopt.GetoptError:
         print_usage()
 
-    return (url, username, password, cmd)
+    return (args_ok, url, host, use_ssl, port, auth, username, password,
+            cert_pem, cert_key_pem, server_cert_validation,
+            cmd, is_powershell_cmd)
 
 
-def run_wsman_cmd(url, username, password, cmd):
+def run_wsman_cmd(url, auth, username, password, cert_pem, cert_key_pem,
+                  server_cert_validation, cmd):
     protocol.Protocol.DEFAULT_TIMEOUT = "PT3600S"
 
+    if not auth:
+        auth = AUTH_BASIC
+
+    auth_transport_map = {AUTH_BASIC: 'plaintext',
+                          AUTH_KERBEROS: 'kerberos',
+                          AUTH_CERTIFICATE: 'ssl'}
+
     p = protocol.Protocol(endpoint=url,
-                          transport='plaintext',
+                          transport=auth_transport_map[auth],
                           username=username,
-                          password=password)
+                          password=password,
+                          cert_pem=cert_pem,
+                          cert_key_pem=cert_key_pem,
+                          server_cert_validation=server_cert_validation)
 
-    shell_id = p.open_shell()
+    shell_id = p.open_shell(codepage=CODEPAGE_UTF8)
 
     command_id = p.run_command(shell_id, cmd[0], cmd[1:])
     std_out, std_err, status_code = p.get_command_output(shell_id, command_id)
@@ -76,14 +134,41 @@ def run_wsman_cmd(url, username, password, cmd):
     return (std_out, std_err, status_code)
 
 
-def main():
-    exit_code = 0
-
-    url, username, password, cmd = parse_args()
-    if not (url and username and password and cmd):
-        exit_code = 1
+def get_url(url, host, use_ssl, port):
+    if url:
+        return url
     else:
-        std_out, std_err, exit_code = run_wsman_cmd(url, username, password,
+        if not port:
+            if use_ssl:
+                port = DEFAULT_PORT_HTTPS
+            else:
+                port = DEFAULT_PORT_HTTP
+
+        if use_ssl:
+            protocol = "https"
+        else:
+            protocol = "http"
+
+        return ("%(protocol)s://%(host)s:%(port)s/wsman" % locals())
+
+
+def main():
+    exit_code = 1
+
+    (args_ok, url, host, use_ssl, port, auth, username, password,
+     cert_pem, cert_key_pem, server_cert_validation,
+     cmd, is_powershell_cmd) = parse_args()
+    if args_ok:
+        url = get_url(url, host, use_ssl, port)
+
+        if is_powershell_cmd:
+            cmd = ["powershell.exe", "-ExecutionPolicy", "RemoteSigned",
+                   "-NonInteractive", "-Command"] + cmd
+
+        std_out, std_err, exit_code = run_wsman_cmd(url, auth, username,
+                                                    password, cert_pem,
+                                                    cert_key_pem,
+                                                    server_cert_validation,
                                                     cmd)
         sys.stdout.write(std_out)
         sys.stderr.write(std_err)