IEEE 802.5 (Token Ring): networks may look like a star physically (with a Multi-Station Access Unit), but they actually operate as which logical topology?

Introduction:
Some LAN technologies separate physical wiring layouts from how frames flow logically. IBM Token Ring (IEEE 802.5) famously used star-wired hubs while still enforcing token-passing ring behavior at the data link layer. Understanding this distinction helps decode exam questions and real-world diagrams.

Given Data / Assumptions:

• Technology: IEEE 802.5 (Token Ring).
• Physical layout often used an MAU (Multi-Station Access Unit) with star cabling.
• Question asks for the operational or logical topology.

Concept / Approach:
Token Ring relies on a circulating token that grants transmit permission in a strict sequence. Even when cabling radiates from a central MAU (star-like), the MAU internally connects ports in a closed loop so the token travels ring-wise. Hence, the logical topology is a ring regardless of the outward star appearance.

Step-by-Step Solution:
1) Identify that Token Ring uses token passing with ordered station access.2) Recognize MAU behavior: it wiring-loops stations to form a ring internally.3) Conclude that frames circulate around a ring path.4) Select “Ring” as the logical topology.

Verification / Alternative check:
Vendor documentation for MAUs shows lobe connections forming an internal loop; bypass relays maintain the ring when a station is disconnected.

Why Other Options Are Wrong:

• Linear bus: single shared backbone; not token passing on a loop.
• Modified star / Hybrid hub: describe physical cabling, not logical frame flow.
• Modified ring: distractor; 802.5 is a standard ring logically.

Common Pitfalls:
Equating the physical star cabling with the logical topology; many technologies (e.g., Wi-Fi mesh, Ethernet switching) also decouple these layers.

Final Answer:
Ring