In data communications, which statement correctly describes protocol converters and how they are typically deployed in practical networks?

Introduction:
Protocol converters are devices or software systems that translate between two dissimilar protocols so that otherwise incompatible endpoints can interoperate. They often appear at network edges, industrial automation boundaries, or between legacy and modern systems, ensuring signaling, framing, timing, and semantics are correctly mapped.

Given Data / Assumptions:

• Two endpoints use different link, network, or application protocols.
• Both directions of traffic must be understood by the far side.
• Goals include functional compatibility, not bandwidth aggregation.

Concept / Approach:
Unlike multiplexers (including TDMs) that combine multiple similar streams onto one link, protocol converters translate format and procedure from protocol A to protocol B and back. In many deployments, translation is needed in both directions so that requests and responses remain intelligible, which is why they are commonly operated in pairs or as bidirectional units with symmetric logic.

Step-by-Step Solution:
1) Identify that the problem is incompatibility, not channel scarcity.2) Choose conversion (A↔B) rather than multiplexing (many A→one A).3) Provide bidirectional conversion so that both sides can initiate and respond.4) Deploy as a pair or a single bidirectional converter to ensure full-duplex interoperability.

Verification / Alternative check:
Industrial gateways (e.g., Modbus↔PROFINET), telephony/media gateways (SIP↔H.323), or serial↔IP protocol bridges all rely on two-way translation logic, confirming the need for paired or bidirectional operation.

Why Other Options Are Wrong:

• Same as multiplexers/TDMs: multiplexing aggregates streams; it does not translate procedures or semantics.
• Not operated in pairs: one-way conversion would break request/response flows.
• None of the above: incorrect because one option is correct.

Common Pitfalls:
Confusing bandwidth aggregation (multiplexing) with protocol translation, or assuming one-way conversion is sufficient for interactive systems.

Final Answer:
Protocol converters are usually operated in pairs to translate in both directions