title: How to Send Packets Between Two IP Hosts on Different Subnets?
body: <p>Host 1：
  10.10.0.1</p>
  
  <p>Host 2：
  10.10.1.2</p>
  
  <p>Mask is both:
  255.255.255.0</p>
  
  <p>How to send a packet from Host 1 to Host 2?</p>