// Requests for nodes on the channel.
  public List<String> getJoinedNodeList(String channelName) {
    Log.d(TAG, TAGClass + "getJoinedNodeList()");
    // Request the channel interface for the specific channel name.
    IChordChannel channel = mChord.getJoinedChannel(channelName);
    if (null == channel) {
      Log.e(TAG, TAGClass + "getJoinedNodeList() : invalid channel instance-" + channelName);
      return null;
    }

    return channel.getJoinedNodeList();
  }