In TCP/IP networking, which item explicitly identifies both the network portion (network ID) and the host portion (host ID) assigned to a computer for end-to-end communication on an IP network?

Introduction:
Every device on an Internet Protocol (IP) network needs a way to be uniquely identified so it can send and receive packets. Conceptually, an IP address contains two parts: a network identifier that tells routers which logical network a host belongs to, and a host identifier that distinguishes the specific device within that network. Understanding which configuration element conveys these two identifiers is a fundamental networking skill and frequently appears in certification and interview questions.

Given Data / Assumptions:

• A host participates in an IPv4 network using standard TCP/IP settings.
• Common settings include IP address, subnet mask, and default gateway.
• We are asked which item specifies the network and host address of the computer.

Concept / Approach:
The IP address assigned to a host encodes both the network ID and the host ID. Historically, classful addressing implied fixed boundaries, but in modern Classless Inter-Domain Routing (CIDR), the network/host split is determined by a prefix length (or mask). While the subnet mask (or prefix) tells where the boundary lies, the actual values of the network and host portions are carried in the IP address itself. The default gateway is merely the next-hop router used for off-subnet traffic and does not encode the host’s identity.

Step-by-Step Solution:
1) Identify the items: IP address, subnet mask, default gateway.2) Recognize that the IP address is a 32-bit value whose high-order bits (per mask) denote network ID and remaining bits denote host ID.3) Note that the subnet mask is a boundary indicator, not an address; it does not by itself identify a host.4) Conclude that the IP address uniquely specifies both the network and host identifiers for the machine.

Verification / Alternative check:
Given an IP (e.g., 192.168.10.34) and a mask (/24), routers compute the network ID (192.168.10.0) by applying the mask to the IP address and infer the host ID (.34) from the remaining bits. This confirms that the IP address carries both values.

Why Other Options Are Wrong:

• The TCP address: no such configuration parameter exists; TCP is a transport-layer protocol.
• The subnet mask: identifies the split position but not the host’s numeric identity.
• The default gateway: a routing next-hop, not an identity descriptor.
• None of the above: incorrect because the IP address is the right choice.

Common Pitfalls:
Students sometimes choose the subnet mask because it “determines” the split. Remember: the mask defines boundaries; the address carries the actual network and host values.

Final Answer:
The IP address