Which protocol is responsible for handling the actual transmission of packets in the Internet software layers?

The protocol responsible for handling the actual transmission of packets in the Internet software layers is the Transmission Control Protocol (TCP) or the Internet Protocol (IP). These protocols are part of the Internet protocol suite, commonly known as TCP/IP.

Here are the steps to understand this:

1. The Internet software layers, also known as the Internet protocol stack, is a set of protocols used for communication over the Internet. The layers are, from top to bottom: Application, Transport, Internet, and Network Interface.

2. The Application layer is where applications (like your web browser or email client) operate.

3. The Transport layer is where Transmission Control Protocol (TCP) operates. TCP is responsible for ensuring that data is reliably transmitted across the network. It does this by breaking down data into packets, transmitting them, and then reassembling them at the destination.

4. The Internet layer is where the Internet Protocol (IP) operates. IP is responsible for delivering packets from the source host to the destination host based on the IP addresses in the packet headers. It does not guarantee reliable transmission, but it does ensure that the packets are routed to the correct destination.

5. The Network Interface layer is responsible for transmitting data over the physical network.

So, in summary, the actual transmission of packets is handled by TCP at the Transport layer and IP at the Internet layer.