HowTo Work with proxy

Setting a proxy for your browser

Example for an HTTP and SSL proxy

$wd_host = 'http://localhost:4444/wd/hub';  
$capabilities = array(WebDriverCapabilityType::BROWSER_NAME => 'firefox',  
                      WebDriverCapabilityType::PROXY => array('proxyType' => 'manual',  
                      'httpProxy' => '127.0.0.1:2043', 'sslProxy' => '127.0.0.1:2043'));  
$driver = RemoteWebDriver::create($wd_host, $capabilities);

See https://code.google.com/p/selenium/wiki/DesiredCapabilities#Proxy_JSON_Object for more options.

To use a proxy with a basic authentication for Chrome/Chromium, you need tu use a plugin. Details https://github.com/RobinDev/Selenium-Chrome-HTTP-Private-Proxy