title: Reliable Multicast Library C++
body: <p><img src="https://i.stack.imgur.com/NaBeP.png" alt="enter image description here">                                                              </p>
  
  <p>I am aware of <a href="https://stackoverflow.com/questions/11992567/reliable-multicast-over-local-network">this</a> and <a href="https://stackoverflow.com/questions/31199565/methods-for-implementing-udp-multicast-reliable">this</a> stackoverflow questions which answers known methods to achieve "Reliable Multicast" but off-late I have come across some websites which mentions even routers should also be programmed to handle custom protocols which are designed over UDP, is that true?</p>
  
  <p>Basically I want to use Multicast for my application and I want don't want to impose any restriction of changing router for configuring custom protocol to handle UDP in reliable way , for example I was thinking for implementing/using PGM protocol over UDP to handle multicast but someone said that router should also have support for PGM which restricts me in providing solution since customers should change infrastructure for my solution which is unwarranted. </p>
  
  <p>Please let me know if there is any solution which I can implement to handle UDP packets in reliable way without any changes to network infrastructure.</p>
  
  <p>Thanks in advance. </p>
  
  <p>EDIT:</p>
  
  <p>I don't mean to say that I don't want to enable multicast in router, I would definitely enable multicast routing in router. When I read about PGM implementation some one said even router should be PGM capable which I thought is different router than commercially available routers in stores. Is my understanding wrong?  </p>