When doing IPC using TCP/IP sockets using the loopback address, do common networking stacks skip framing the message in lower-level PDUs?

Question

In some environments such as Java, it\'s natural to use TCP/IP sockets to pass messages between processes on the same host using the \'localhost\' address (127.0.0.1 in IPv4, or

Answer 1

Yes. When a packet/data to a Loopback address(127.x.x.x) is received, the IP layer of the TCP/IP uses the Loopback route to route the packet to itself.

Looback Route

Network Destination || Netmask || Gateway || Interface || Metric

127.0.0.0 |||||||||||||||||||||| 255.0.0.0 || 127.0.0.1|| 127.0.0.1 || 1

After routing it to itsef, at TCP/UDP layer with the help of protocol control blocks(per connection data structure) the corresponding socket and its owner process will be identified to deliver the packet/data.

Bottom line, All the tasks at Data Link layers and Physical layers(of OSI Model) will be avoided.