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Catalyst 3750-X and 3560-X Switch Software Configuration Guide
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Chapter 1 Overview Network Configuration Examples
Multidwelling Network Using Catalyst 3750-X Switches
A growing segment of residential and commercial customers are requiring high-speed access to Ethernet
metropolitan-area networks (MANs). Figure 1-11 shows a configuration for a Gigabit Ethernet MAN
ring using multilayer switch stacks as aggregation switches in the mini-point-of-presence (POP)
location. These switches are connected through 1000BASE-X SFP module ports.
The resident switches can be Catalyst 3750-X switches, providing customers with high-speed
connections to the MAN. The Catalyst 2950 LRE switch can also be used as a residential switch for
customers requiring connectivity through existing phone lines. The Catalyst 2950 LRE switch can then
connect to another residential switch or to a Catalyst 3750 aggregation switch. For more information
about the Catalyst Long-Reach Ethernet (LRE) switches, see the documentation sets specific to these
switches for LRE information.
All ports on the residential Catalyst 3750-X switches (and Catalyst 2950 LRE switches if they are
included) are configured as IEEE 802.1Q trunks with protected port and STP root guard features
enabled. The protected port feature provides security and isolation between ports on the switch, ensuring
that subscribers cannot view packets destined for other subscribers. STP root guard prevents
unauthorized devices from becoming the STP root switch. All ports have IGMP snooping or CGMP
enabled for multicast traffic management. ACLs on the uplink ports to the aggregating Catalyst 3750
multilayer switches provide security and bandwidth management.
The aggregating switches and routers provide services such as those described in the examples in the
“Small to Medium-Sized Network Using Catalyst 3750-X and 3560-X Switches” section on page 1-26
and the “Large Network Using Catalyst 3750-X and 3560-X Switches” section on page 1-28.