SO_REUSEADDR: The best explanation I have ever read on this is at this StackOverflow thread.
SO_EXCLUSIVEADDRUSE: Stops another socket forceably binding to this port
SO_BINDTODEVICE: Bind this socket to a particular device like "l;eth0"
SO_BROADCAST: When enabled, datagram sockets are allowed to send packets to a broadcast address.
IP_MULTICAST_IF and IP_ADD_MEMBERSHIP: Useful when doing multicast transmission and reception. Use IP_MULTICAST_IF to specify a specific interface for a socket to use. Use IP_ADD_MEMBERSHIP ro register interest in a multicast group. [Ref].
Virtual LANs (VLANs)
- Article "VLAN Basic Concepts Explained with Examples"
"Not member": This port is not a member of the VLAN.
"Tagged": The packets have already a VLAN-tag, i.e. they are tagged by the network device connected to this port.
"Untagged": The packets at this port have no VLAN-tags, so the incoming packets are tagged by the switch and the outgoing packets are untagged by the switch.