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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
OL-21521-01
Chapter 1 Overview
Network Configuration Examples
Figure 1-8 Catalyst 3560-X Switches in a Collapsed Backbone Configuration
Large Network Using Catalyst 3750-X and 3560-X Switches
Switches in the wiring closet have traditionally been only Layer 2 devices, but as network traffic profiles
evolve, switches in the wiring closet are increasingly employing multilayer services such as multicast
management and traffic classification. Figure 1-9 shows a configuration for a network that uses only
Catalyst 3750-X switch stacks in the wiring closets and two backbone switches, such as the
Catalyst 6500 switches, to aggregate up to ten wiring closets. Figure 1-10 shows a configuration for a
network that uses only Catalyst 3560-X switches in the wiring closets and two backbone switches, such
as the Catalyst 6500 switches, to aggregate up to ten wiring closets.
In the wiring closet, each switch stack or switch has IGMP snooping enabled to efficiently forward
multimedia and multicast traffic. QoS ACLs that either drop or mark nonconforming traffic based on
bandwidth limits are also configured on each switch stack or switch. VLAN maps provide intra-VLAN
security and prevent unauthorized users from accessing critical pieces of the network. QoS features can
limit bandwidth on a per-port or per-user basis. The switch ports are configured as either trusted or
untrusted. You can configure a trusted port to trust the CoS value, the DSCP value, or the IP precedence.
If you configure the port as untrusted, you can use an ACL to mark the frame in accordance with the
network policy.
Each switch stack or switch provides inter-VLAN routing. They provide proxy ARP services to get IP
and MAC address mapping, thereby removing this task from the routers and decreasing this type of
traffic on the WAN links. These switch stacks or switches also have redundant uplink connections to the
backbone switches, with each uplink port configured as a trusted routed uplink to provide faster
convergence in case of an uplink failure.
The routers and backbone switches have HSRP enabled for load-balancing and redundant connectivity
to guarantee mission-critical traffic.
Gigabit
servers
200860
Cisco 2600 or
3700 routers
Standalone
switches
Internet
Cisco IP
phones Workstations
running
Cisco SoftPhone
software
IP IP
Aironet wireless
access points