© 2005 Cisco Systems, Inc. All rights reserved. INTRO v Module Summary The topology of a network describes the layout of the cabling and devices and also the paths used in data transmissions. There are both physical (bus, star, ring, and mesh) and logical topologies. Ethernet cables and segments can only span a limited physical distance, but there are devices, such as repeaters and hubs, that can be added to an Ethernet LAN to extend segments. Bridges and switches divide a LAN into multiple segments. However, switches operate at much higher speeds and support more advanced functionality, performing three major functions in segmenting an Ethernet network: forwarding, filtering, and flooding. There are a number of ways in which the performance benefits of switched Ethernet LANs can be enhanced, including microsegmentation and connectivity hierarchies; however, there is a potential for intentional or unintentional physical loops that can be solved by Spanning-Tree Protocol.

© 2005 Cisco Systems, Inc. All rights reserved. INTRO v2.13-2