Gigabit Ethernet ports for GBIC Ethernet aggregation. It also has built−in support for Voice Over IP telephony, in addition to built−in support for up to 250 port−based VLANs and ISL VTP.

In addition, the 3500 series supports many of the features of the 1900 and 2900 series, such as DNS and DHCP. The series is offered in both Standard and Enterprise Editions. Table E.6 shows the features of the Catalyst 3500 series.

Table E.6: The Cisco Catalyst 3500 series key switching features.

Cisco Catalyst 3900 Series

The Catalyst 3900 and 3920 are low−cost solutions for Token Ring users to migrate from a shared−media hub to a switched environment. Like the 3500 series, the 3900 is a stackable switch with the ability to provide a variety of high−speed uplinks, network management, and support for multiple VLANs.

The Catalyst 3900 provides an ISL module for connections between wiring closets. This module consists of two ports, which can be either fiber or copper. Two feature cards can be used in the 3900. This link can provide up to 100Mbps uplink connectivity. Also supported is an ATM module that provides Token Ring users with ATM access to campus backbones. The module provides a single 155Mbps connection with a multimode fiber interface. In addition, optional four−port Token Ring modules can be added to the expansion ports in the Catalyst 3900. These cards allow for expansion of up to 28 Token Ring ports. Up to eight units can be stacked using the optional stack port module and the Catalyst Matrix, for a total of 224 Token Ring ports. The four−port fiber module supports IEEE 802.5J standard for ring−in/ring−out (RI/RO) and the fiber lobe attachment of end stations.

The Catalyst Switch Matrix is an eight−port interface that connects up to eight Catalyst 3900 series switches. A Cisco Catalyst 3900 has the ability to detect if it is connected to another Catalyst 3900 switch that is connected to a Catalyst Matrix. The connected Catalyst 3900 series switches then connect in the switch block to make a stack that logically appears to be one switch.

One of the great features of the Catalyst Matrix in the 3900 series is the switch’s ability to connect any combination of up to eight Catalyst 3900 switches or to remove any one switch without needing to have the power cycled or turned off. A Cisco Systems proprietary shielded cable (1 meter long, with a 50−pin connector at each end) is used to connect the switches participating in the switch stack. The cable uses cross−over wiring so either end can be used for either side of the connection. The cable plugs into a stack port I/O connector on the back of each Catalyst Matrix. The other end of the cable is plugged into a Catalyst stack port module interface card that is installed in an expansion slot on another Catalyst 3900 series switch.

The 3900 series supports three types of bridging:

∙Source Route Bridging (SRB)

∙Source Route Transparent Bridging (SRT)

∙Source Route Switched Bridging

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