Large Network Using Catalyst 3560 Switches - Cisco WS-C3560-48PS-S Software Configuration Manual

Network Configuration Examples
Cisco CallManager controls call processing, routing, and IP phone features and configuration. Users
with workstations running Cisco SoftPhone software can place, receive, and control calls from their PCs.
Using Cisco IP Phones, Cisco CallManager software, and Cisco SoftPhone software integrates telephony
and IP networks, and the IP network supports both voice and data.
With the multilayer switches providing inter-VLAN routing and other network services, the routers
focus on firewall services, Network Address Translation (NAT) services, voice-over-IP (VoIP) gateway
services, and WAN and Internet access.
Figure 1-1

Large Network Using Catalyst 3560 Switches

Switches in the wiring closet have traditionally been Layer 2-only devices, but as network traffic profiles
evolve, switches in the wiring closet are increasingly employing multilayer services such as multicast
management and traffic classification.
Catalyst 3560 multilayer 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 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. 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 provides inter-VLAN routing. They provide proxy ARP services to determine IP and MAC
address mapping, thereby removing this task from the routers and decreasing this type of traffic on the
WAN links. These 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.
Catalyst 3560 Switch Software Configuration Guide
1-14
Catalyst 3560 Switches in a Collapsed Backbone Configuration
Internet
Cisco 2600 or
3700 routers
IP IP
Cisco IP
Workstations
phones
running
Cisco SoftPhone
software
Aironet wireless
access points
Figure 1-2 shows a configuration for a network only using
Chapter 1 Overview
Gigabit
servers
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