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Catalyst 2950 Desktop Switch Software Configuration Guide
78-14982-01
Chapter 1      Overview
Network Configuration Examples
Bandwidth alone is not the only consideration when designing your network. As your network traffic 
profiles evolve, consider providing network services that can support applications such as voice and data 
integration and security. 
Table 1-3 describes some network demands and how you can meet those demands.
Figure 1-1 shows configuration examples of using the Catalyst switches to create these networks:
• Cost-effective wiring closet—A cost-effective way to connect many users to the wiring closet is to 
connect up to nine Catalyst 2900 XL, Catalyst 2950, Catalyst 3500 XL, and Catalyst 3550 switches 
through GigaStack GBIC connections. When you use a stack of Catalyst 2950G-48 switches, you 
can connect up to 432 users. To preserve switch connectivity if one switch in the stack fails, connect 
the bottom switch to the top switch to create a GigaStack loopback, and enable cross-stack 
UplinkFast on the cross-stack Gigabit uplinks.
Table 1-2 Increasing Network Performance
Network Demands Suggested Design Methods
Too many users on a single network segment 
and a growing number of users accessing the 
Internet
• Create smaller network segments so that fewer users share the 
bandwidth, and use VLANs and IP subnets to place the network 
resources in the same logical network as the users who access those 
resources most.
• Use full-duplex operation between the switch and its connected 
workstations.
• Increased power of new PCs, 
workstations, and servers
• High demand from networked 
applications (such as e-mail with large 
attached files) and from 
bandwidth-intensive applications (such 
as multimedia)
• Connect global resources—such as servers and routers to which network 
users require equal access—directly to the Fast Ethernet or Gigabit 
Ethernet switch ports so that they have their own Fast Ethernet or 
Gigabit Ethernet segment.
• Use the Fast EtherChannel or Gigabit EtherChannel feature between the 
switch and its connected servers and routers.
Table 1-3 Providing Network Services
Network Demands Suggested Design Methods
High demand for multimedia support
• Use IGMP and MVR to efficiently forward multicast traffic.
High demand for protecting mission-critical 
applications
• Use VLANs and protected ports to provide security and port isolation.
• Use VLAN trunks, cross-stack UplinkFast, and BackboneFast for 
traffic-load balancing on the uplink ports so that the uplink port with a 
lower relative port cost is selected to carry the VLAN traffic.
An evolving demand for IP telephony
• Use QoS to prioritize applications such as IP telephony during 
congestion and to help control both delay and jitter within the network. 
• Use switches that support at least two queues per port to prioritize voice 
and data traffic as either high- or low-priority, based on 802.1P/Q.
A growing demand for using existing 
infrastructure to transport data and voice from 
a home or office to the Internet or an intranet at 
higher speeds
• Use the Catalyst 2950 LRE switches to provide up to 15 Mb of IP 
connectivity over existing infrastructure (existing telephone lines).