public String renderSummary() {
    StringBuilder builder = new StringBuilder();
    builder.append("<fieldset>");
    builder.append("<legend>").append(proxy.getClass().getSimpleName()).append("</legend>");
    builder.append("listening on ").append(proxy.getRemoteHost());
    if (proxy.getTimeOut() > 0) {
      int inSec = proxy.getTimeOut() / 1000;
      builder.append("test session time out after ").append(inSec).append(" sec.");
    }

    builder
        .append("<br>Supports up to <b>")
        .append(proxy.getMaxNumberOfConcurrentTestSessions())
        .append("</b> concurrent tests from : </u><br>");

    for (TestSlot slot : proxy.getTestSlots()) {
      builder.append(
          slot.getCapabilities().containsKey(BROWSER)
              ? slot.getCapabilities().get(BROWSER)
              : slot.getCapabilities().get(APP));
      builder.append("protocol:" + slot.getProtocol() + "<br>");
      TestSession session = slot.getSession();
      builder.append(session == null ? "(free)" : "(busy, session " + session + ")");
      builder.append("<br>");
    }
    builder.append("</fieldset>");
    return builder.toString();
  }