What are the components of an IP address?

An IP address consists of two primary components: the host portion and the network portion. The network portion identifies the specific network a device belongs to, while the host portion identifies the specific device within that network. This separation is crucial for routing traffic on the internet, as routers utilize the network portion to forward packets to the correct destination network, and then the host portion helps to deliver the packet to the correct device within that network.

The other options refer to concepts that, while related to networking, do not accurately describe the fundamental components of an IP address as defined by the Internet Protocol. For example, the network identifier and subnet mask relate to how networks are structured and managed but do not break down the IP address itself into its core components. Similarly, modem IDs and router addresses are not part of the IP address structure, and IP blocks and hostnames refer to broader concepts of addressing and naming in networking rather than the composition of an IP address. Thus, the distinction between the host and network portions is essential for understanding how IP addresses function in the context of networking and internet connectivity.