Cisco Systems RJ-45-to-AUX manual Challenges, Today’s Trend

snmp−server	Modify SNMP parameters
spantree	Spanning tree subsystem
spantree−template	Set bridge template parameter
storm−control	Configure broadcast storm control parameters
switching−mode	Sets the switching mode
tacacs−server	Modify TACACS query parameters
tftp	Configure TFTP
uplink−fast	Enable Uplink fast
vlan	VLAN configuration
vlan−membership	VLAN membership server configuration
vtp	Global VTP configuration commands
SeansSwitch(config)#

Notice that as you progress through the modes on the Cisco IOS, more and more commands become available.

Tip	If your switch does not boot correctly, it may mean that you are in ROM Configuration mode,
	which is covered in Chapter 2.

The Challenges

Sending data effectively through the network is a challenge for network designers and administrators regardless of the LAN topology. The first data−processing environments consisted mostly of time−sharing networks that used mainframes and attached terminals. Communications between devices were proprietary and dependent on your equipment vendor. Both IBM’s System Network Architecture (SNA) and Digital’s network architecture implemented such environments.

In today’s networks, high−speed LANs and switched internetworks are universally used, owing largely to the fact that they operate at very high speeds and support such high−bandwidth applications as voice and video conferencing. Internetworking evolved as a solution to three key problems: isolated LANs, duplication of resources, and a lack of network management.

Implementing a functional internetwork is no simple task. You will face many challenges, especially in the areas of connectivity, reliability, network management, and flexibility. Each area is important in establishing an efficient and effective internetwork. The challenge when connecting various systems is to support communication between disparate technologies. Different sites, for example, may use different types of media, or they may operate at varying speeds.

Reliable service is an essential consideration and must be maintained in any internetwork. The entire organization sometimes depends on consistent, reliable access to network resources to function and to prosper. Network management must provide centralized support and troubleshooting capabilities. Configuration, security, performance, and other issues must be adequately addressed for the internetwork to function smoothly. Flexibility, the final concern, is necessary for network expansion and new applications and services, among other factors.

Today’s Trend

In today’s networks, the trend is to replace hubs and bridges with switches. This approach reduces the number of routers connecting the LAN segments while speeding the flow of data in the network. A smart network administrator uses switches to inexpensively increase network bandwidth and ease network administration.

A switch is a low−cost solution to provide more bandwidth, reduce collisions, filter traffic, and contain broadcasts. But, switches don’t solve all network routing problems. Routers provide a means of connecting

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