Chapter 1. Switching Connectivity
This book is all about switches, which are network devices that provide local-area network (LAN) connectivity for end devices such as servers, PCs, and printers. This book focuses almost entirely on Ethernet switches, which have become the most popular Layer 2 devices in modern networks. Cisco has traditionally been famous for their router, which is a Layer 3 device. In the past decade or so, Cisco has heavily invested in producing market-leading LAN switches, and consequently now holds the number one position worldwide in terms of LAN switch sales. In the past few years, switches have also evolved from being just Layer 2 devices that understand only Layer 2 operations to intelligent devices that possess an understanding of the Layer 3/4 parameters that define different types of traffic possess the ability to act as a high-performance Layer 3 router on the LAN in some platforms (referred to as Layer 3 switching). Cisco's switch portfolio is comprised of the Cisco Catalyst product family, which provides traditional Layer 2 switches, Layer 2 switches that possess Layer 3/4 intelligence, and Layer 3 switches that combine switching and routing features.
In this chapter, you learn the basics of configuring a Cisco Catalyst switch. You learn how to identify the switch and prepare it for placement on the network so that it can be remotely managed via IP and provide LAN connectivity for devices. It is important that you have a firm grasp of the concepts presented in this chapter, because they provide the underlying foundation for the enabling of other switching features that are presented in subsequent chapters. The chapter begins by giving a brief product view of the various Cisco Catalyst switches and then delves straight into some practical scenarios, where you learn how to configure Cisco Catalyst switches and provide connectivity for end devices attached to the LAN. The following scenarios are presented in this chapter: