Should a C/C++-developer be aware of the protocols IGMP and BGP to use multicast?

Question

Do I need to know about the protocols IGMP and BGP (one of PIM) when I write C/C++-code for multicast, or IGMP/BGP works fully automatically and transparently to me?

And is properly that for different IP-addresses of multicast groups different protocols build routes?

IGMP: 224.0.0.0 - 224.0.0.255
BGP: 224.0.1.0 - 238.255.255.255

And whad do I need to know about IGMP/BGP for using UDP-multicast?

At least for IGMP you need to take care about sending the join request, and another when you leave the multicast group. — πάντα ῥεῖ, Sep 11 '15 at 11:16

score 2 · Accepted Answer · answered Sep 11 '15 at 12:24

As far as IGMP goes, it's not something you need to worry about explicitly.

When you call setsockopt with either IP_ADD_MEMBERSHIP or IP_DROP_MEMBERSHIP (or MCAST_JOIN_GROUP or MCAST_LEAVE_GROUP, among others), the OS will automatically send out the appropriate IGMP messages in addition to setting the specified interface to accept / not accept packets from the given multicast group.

Should a C/C++-developer be aware of the protocols IGMP and BGP to use multicast?

1 Answers1