Repeaters vs hubs vs bridges vs switches

Hubs vs switches

Hubs and switches are both networking devices that connect multiple devices in a LAN, but they operate very differently at the data link layer (Layer 2) of the OSI model. Switches are vastly superior to hubs in speed, efficiency, and security—and are considered "intelligent devices" when compared to hubs. Hubs are obsolete in modern networks due to their broadcast nature and shared bandwidth limitations.

Hubs vs Switches: Key Differences

Feature	Hub (Layer 1)	Switch (Layer 2)
Function	Multi-port repeater (broadcasts to all ports)	Multi-port bridge (intelligent forwarding)
Traffic Handling	Broadcasts all incoming data to all ports (flooding)	Forwards traffic only to the destination port using MAC addresses
Collision Domain	Single collision domain (all devices share bandwidth)	Per-port collision domain (isolates traffic, full-duplex possible)
Bandwidth Usage	Shared bandwidth (e.g., 10Mbps hub divides bandwidth among all ports)	Dedicated bandwidth per port (e.g., 100Mbps per port)
MAC Address Learning	No (does not track devices)	Yes (maintains a MAC address table for forwarding decisions)
Ports	4–12 ports (multi-port repeater)	4–48+ ports (scalable)
Performance	Slower (due to collisions and unnecessary traffic)	Faster (efficient forwarding, no unnecessary broadcasts)
Security	Less secure (all devices see all traffic)	More secure (isolates traffic between ports)
Use Case	Obsolete (used in early networks)	Modern standard (used in all current networks)

What Can Switches Do That Hubs Cannot?

1. MAC Address Learning & Forwarding – Switches maintain a MAC address table to send frames only to the correct port, while hubs blindly broadcast.

2. Full-Duplex Communication – Switches allow simultaneous two-way communication (send & receive at the same time), whereas hubs operate in half-duplex (collisions occur).

3. Collision Avoidance – Switches eliminate collisions via per-port segmentation, unlike hubs, which suffer from CSMA/CD (Carrier Sense Multiple Access with Collision Detection).

4. VLAN Support – Switches can segment networks into VLANs (Virtual LANs), while hubs cannot.

5. Traffic Optimization – Switches reduce unnecessary traffic, improving efficiency, whereas hubs waste bandwidth.

Repeaters vs hubs vs bridges vs switches

Bridges were an early improvement over hubs but were later replaced by switches, which offer more ports, faster forwarding, and better scalability.

Repeaters vs Hubs vs Bridges vs Switches: Key Differences

Feature	Repeater (L1)	Hub (L1)	Bridge (L2)	Switch (L2, Advanced)
Function	Regenerates signals (extends cable reach)	Multi-port repeater (broadcasts to all ports)	Connects two network segments (filters by MAC)	Multi-port bridge (intelligent forwarding)
Traffic Handling	No filtering (boosts signal only)	Broadcasts to all ports (no intelligence)	Forwards based on MAC table (2 ports only)	Forwards based on full MAC table (per-port)
Collision Domain	Extends collision domain (no isolation)	Single collision domain (all ports share bandwidth)	Splits collision domains (two segments)	Per-port collision domain (full-duplex possible)
Bandwidth Usage	No improvement (just extends signal)	Shared (e.g., 10Mbps divided among all ports)	Reduces unnecessary traffic (basic filtering)	Dedicated per port (e.g., 100Mbps per port)
MAC Learning	No (dumb signal booster)	No (dumb device)	Yes (basic MAC table for two ports)	Yes (full MAC table for all ports)
Ports	2 ports (in/out)	4–12 ports (multi-port repeater)	2 ports (links two hubs/segments)	4–48+ ports (scalable)
Performance	No speed improvement (just extends range)	Slow (collisions, broadcasts)	Moderate (reduces collisions but limited ports)	Fast (no collisions, optimized forwarding)
Security	None (raw signal passthrough)	None (all traffic visible to all devices)	Basic filtering (isolates segments)	Better isolation (per-port forwarding, VLAN support)
Use Case	Extending cable runs (e.g., Ethernet, fiber)	Obsolete (historical use)	Legacy segmentation (older networks)	Modern standard (all Ethernet networks)

Key Notes

1. Repeaters extend signals but do nothing for traffic efficiency.

2. Hubs are just multi-port repeaters—they flood all traffic, creating congestion.

3. Bridges sit between hubs and switches in terms of functionality; improve on hubs by splitting collision domains but are limited to 2 ports.

4. Switches are scalable, high-performance bridges with per-port forwarding (full MAC tables, dedicated bandwidth, VLANs, high port density).