NETWORK CONNECTIVITY DEVICES: REPEATERS, HUBS, BRIDGES, SWITCHES & ROUTERS Michael Armand Danielle DiLuzio Ronnie Hedrick

Connectivity Devices Physical Layer Repeaters Hubs Data Link Layer Bridges Switches Network Layer Routers Overview

Repeaters Physical Layer of the OSI Model Simplest type of connectivity device which regenerates digital signals Extend a network inexpensively Limitations: Non-intelligent One input port and one output port Suited only to bus topologies Physical Layer

Hubs Physical Layer of the OSI Model Limitations: Non-intelligent connectivity device Lack of security Physical Layer

Poor Performance of Hub-Based LANs

The Rule

The Physical Layer: Repeaters vs. Hubs Simplest type of connectivity device Regenerates digital signals from one input port to one output port Not as common since they can only be used with bus topologies REPEATERS Connectivity device similar to Repeaters Regenerates digital signals to multiple ports – all devices attached HUBS

Bridges Data Link Layer of the OSI Model Establish connections using the MAC address of each device Reduce traffic on a LAN by dividing it into two segments Data Link Layer

Switches Data Link Layer of the OSI Model Intelligent connectivity device (i.e., has decision-making capability) Establish connections using the MAC address of each device Simultaneous data transfer is possible Figure 6-18 A switch on a small network Data Link Layer

The Data Link Layer: Bridges vs. Switches Connectivity device used to connect two networks only Has only two ports Uses software and is therefore slower than a switch Use MAC address BRIDGES Connectivity device used to connect multiple networks Has more than two ports & more configuration possibilities Use MAC address SWITCHES

Routers Network Layer of the OSI Model Allow one or more computers to connect with each other, other networked devices, or to other networks like the Internet Network Layer

SUMMARY