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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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