Cisco 3750 - Catalyst EMI Switch User manual

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Data Sheet
Cisco Catalyst 3750 Series Switches
The Cisco Catalyst 3750 Series switches are an innovative product line that
improves LAN operating efficiency by combining industry-leading ease of use
and the highest resiliency available for stackable switches. This product series
represents the next generation in desktop switches, and features Cisco StackWise
™
technology, a 32-Gbps stack interconnect that allows customers to build a unified,
highly resilient switching system—one switch at a time.
Figure 1
Cisco Catalyst 3750 Series Switches for 10/100 and 10/100/1000 Access and Aggregation
Figure 2
Cisco Catalyst 3750-24PS and Cisco Catalyst 3750-48PS with IEEE 802.3af Power
Figure 3
Cisco Catalyst 3750G-16TD with a 10Gigabit Ethernet XENPAK Uplink

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For mid-sized organizations and enterprise branch offices, the Cisco Catalyst 3750 Series eases deployment of
converged applications and adapts to changing business needs by providing configuration flexibility, support for
converged network patterns, and automation of intelligent network-services configurations. In addition, the
Cisco Catalyst 3750 Series is optimized for high-density Gigabit Ethernet deployments and includes a diverse
range of switches that meet access, aggregation, or small-network backbone-connectivity requirements.
Configurations
• Cisco Catalyst 3750G-24TS—24 Ethernet 10/100/1000 ports and 4 SFP uplinks
• Cisco Catalyst 3750G-24T—24 Ethernet 10/100/1000 ports
• Cisco Catalyst 3750G-12S—12 Gigabit Ethernet SFP ports
• Cisco Catalyst 3750-48TS—48 Ethernet 10/100 ports and 4 SFP uplinks
• Cisco Catalyst 3750-24TS—24 Ethernet 10/100 ports and 2 small form-factor pluggable (SFP) uplinks
• Cisco Catalyst 3750-48PS—48 Ethernet 10/100 ports and 4 SFP uplinks with IEEE 802.3af and Cisco
pre-standard Power over Ethernet (PoE)
• Cisco Catalyst 3750-24PS—24 Ethernet 10/100 ports and 2 SFP uplinks with IEEE 802.3af and Cisco
pre-standard Power over Ethernet (PoE)
• Cisco Catalyst 3750G-16TD-16 Gigabit Ethernet 10/100/1000 ports and 1 10Gigabit Ethernet XENPAK uplink
Cisco Catalyst 3750 Series is available in the Standard Multilayer Software Image (SMI) or the Enhanced Multilayer
Software Image (EMI). The SMI feature set includes advanced quality of service (QoS), rate-limiting, access control
lists (ACLs), and basic static and routed information protocol (RIP) routing functionality. The EMI provides a richer
set of enterprise-class features including advanced hardware-based IP unicast and multicast routing.
Cisco StackWise Technology—A New Standard in Stackable Resiliency
Cisco StackWise technology is a premium stacking architecture optimized for Gigabit Ethernet. This technology
is designed to respond to additions, deletions, and redeployment while maintaining constant performance.
Cisco StackWise technology unites up to nine individual Cisco Catalyst 3750 switches into a single logical unit, using
special stack interconnect cables and stacking software. The stack behaves as a single switching unit that is managed
by a master switch elected from one of the member switches. The master switch automatically creates and updates
all the switching and optional routing tables. A working stack can accept new members or delete old ones without
service interruption.
Key Features and Benefits
Ease of Use—“Plug-and-Play” Configuration
A working stack is self-managing and self-configuring. When switches are added or removed, the master switch
automatically updates all the routing tables to reflect changes. Upgrades are applied universally and simultaneously
to all members of the stack.

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Scalability—Fast Ethernet to Gigabit Ethernet
The Cisco Catalyst 3750 Series stacks up to 9 switches as a single logical unit for a total of 468 Ethernet or Power
over Ethernet 10/100 ports or 252 Ethernet 10/100/1000 ports, or 9 10Gigabit Ethernet ports. Individual 10/100
and 10/100/1000 and 10Gigabit Ethernet units may be joined in any combination to evolve with network needs.
Mix-and-Match Switch Types—Pay as You Expand Your Network
Stacks can be created with any combination of Cisco Catalyst 3750 switches. Customers who need a mixture of
10/100, 10/100/1000 ports, Power over Ethernet, and wiring closet aggregation capability can incrementally develop
the access environment, paying only for what they need. When uplink capacity needs to be increased customers
can easily upgrade their bandwidth by adding a 10Gigabit Ethernet version to the stack and upgrade their one
Gigabit Ethernet links with 10Gigabit Ethernet on the existing fiber.
Availability—Non-Stop Performance at Layer 2 and Layer 3
The Cisco Catalyst 3750 Series increases availability for stackable switches. Each switch can operate both as master
controller and forwarding processor. Each switch in the stack can serve as a master, creating an 1:N availability
scheme for network control. In the unlikely event of a single unit failure, all other units continue to forward traffic
and maintain operation.
Smart Multicast—A New Level of Efficiency for Converged Networks
With Cisco StackWise technology, the Cisco Catalyst 3750 Series offers greater efficiency for multicast applications
such as video. Each data packet is put on to the backplane only once, which provides more effective support for more
data streams.
Superior Quality of Service—Across the Stack and at Wire Speed
The Cisco Catalyst 3750 Series offers Gigabit Ethernet speed with intelligent services that keep everything flowing
smoothly—even at ten times normal network speed. Industry-leading mechanisms for marking, classification, and
scheduling deliver best-in-class performance for data, voice, and video traffic—all at wire speed.
Security—Granular Control for the Access Environment
The Cisco Catalyst 3750 Series supports a comprehensive set of security features for connectivity and access control,
including ACLs, authentication, port-level security, and identity-based network services with 802.1x and extensions.
Single IP Management—Many Switches, One Address
Each Cisco Catalyst 3750 Series stack is managed as a single object and has a single IP address. Single IP management
is supported for activities such as fault detection, virtual LAN creation and modification, security, and QoS controls.
Jumbo Frames—Support for High-Demand Applications
The Cisco Catalyst 3750 Series supports jumbo frames on the 10/100/1000 configurations for advanced data and
video applications requiring very large frames.

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IPv6 Capable—Getting Ready for the Future
The Catalyst 3750 supports IPv6 routing in hardware for maximum performance. As network devices grow and
the need for larger addressing and higher security become necessary, the Catalyst 3750 will be ready to meet the
requirement.
Standard Power over Ethernet Support—Graceful Addition of IP Communications
The Catalyst 3750 Power over Ethernet (PoE) models support Cisco IP phones and Cisco Aironet wireless
LAN access points, as well as any IEEE 802.3af compliant end device. The Catalyst 3750 24-port version can support
24 simultaneous full powered PoE ports at 15.4 Watts for maximum powered device support. The 48-port version
can deliver the necessary power to support 24 ports at 15.4 W, 48 ports at 7.7 W, or any combination in-between.
10Gigabit Ethernet Support—Increase Uplink Bandwidth For Gigabit Ethernet Deployments
The Catalyst 3750 allows network managers to incrementally add 10GbE connectivity in their wiring closets or
GRID clusters, further enabling and enhancing Gigabit Ethernet networks. This provides investment protection to
customers who wish to utilize their existing fiber plant, add uplink bandwidth capacity to their switching stacks, and
who want to provide higher performance to applications and users.
Management Options
The Cisco Catalyst 3750 Series offers both a superior command-line interface (CLI) for detailed configuration
and Cisco Cluster Management Suite (CMS) Software, a Web-based tool for quick configuration based on pre-set
templates. In addition, CiscoWorks supports the Cisco Catalyst 3750 Series for network-wide management.
Figure 4
Cisco Catalyst 3750 Series Switches

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Product Specifications
Table 1 Product Features and Benefits
Feature Benefit
Ease of Use and Deployment • Auto-configuration of new stack units eliminates reconfiguration.
• Dynamic Host Configuration Protocol (DHCP) auto-configuration of multiple
switches through a boot server eases switch deployment.
• Automatic Cisco IOS Software version checking and updating helps ensure that
all stack members have the same software version.
• Automatic QoS (AutoQoS) simplifies QoS configuration in voice-over-IP (VoIP)
networks by issuing interface and global switch commands to detect Cisco IP
phones, classify traffic, and enable egress queue configuration.
• Master configuration management ensures that all switches are automatically
upgraded when the master switch receives a new software version.
• Auto-sensing on each non-SFP port detects the speed of the attached device and
automatically configures the port for 10-, 100-, or 1000-Mbps operation, easing
switch deployment in mixed 10, 100, and 1000BASE-T environments.
• Auto-negotiating on all ports automatically selects half- or full-duplex
transmission mode to optimize bandwidth.
• Dynamic Trunking Protocol (DTP) enables dynamic trunk configuration across all
switch ports.
• Port Aggregation Protocol (PAgP) automates the creation of Cisco Fast
EtherChannel groups or Gigabit EtherChannel groups to link to another switch,
router, or server.
• Link Aggregation Control Protocol (LACP) allows the creation of Ethernet
channeling with devices that conform to IEEE 802.3ad. This feature is similar to
Cisco EtherChannel technology and PAgP.
• DHCP Relay allows a DHCP relay agent to broadcast DHCP requests to the
network DHCP server.
• IEEE 802.3z-compliant 1000BASE-SX, 1000BASE-LX/LH, 1000BASE-ZX,
1000BASE-T and CWDM physical interface support through a field-replaceable
SFP module provides unprecedented flexibility in switch deployment.
• To help ensure that the switch can be quickly connected to the network and can
pass traffic with minimal user intervention, there is a default configuration
stored in Flash.
• Auto-MDIX (media-dependent interface cross-over) automatically adjusts
transmit and receive pairs if an incorrect cable type (cross-over or
straight-through) is installed.
Availability/Scalability
Superior Redundancy
for Fault Backup
• 1:N master redundancy allows each stack member to serve as a master,
providing the highest reliability for forwarding.
• Cisco CrossStack UplinkFast (CSUF) technology provides increased redundancy
and network resiliency through fast spanning-tree convergence (less than 2
seconds) across a switch stack with Cisco StackWise Technology.
• Cross-Stack EtherChannel provides the ability to configure Cisco EtherChannel
technology across different members of the stack for high resiliency.
• IEEE 802.1w Rapid Spanning Tree Protocol (RSTP) provides rapid spanning-tree
convergence independent of spanning-tree timers and benefit of distributed
processing.
• Stacked units behave as a single spanning-tree node.

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• Per VLAN Rapid Spanning Tree (PVRST+) allows rapid spanning-tree
reconvergence on a per-VLAN spanning-tree basis, without requiring the
implementation of spanning-tree instances.
• Cisco Hot Standby Router Protocol (HSRP) is supported to create redundant,
failsafe routing topologies.
• Command-switch redundancy enabled in Cisco CMS Software allows
designation of a backup command switch that takes over cluster management
functions if the primary command switch fails.
• UniDirectional Link Detection (UDLD) and Aggressive UDLD allow unidirectional
links caused by incorrect fiber-optic wiring or port faults to be detected and
disabled on fiber-optic interfaces.
• Switch port auto-recovery (errdisable) automatically attempts to re-enable a link
that is disabled due to a network error.
• Cisco Redundant Power System 675 (RPS 675) support provides superior
power-source redundancy for up to 6 Cisco networking devices, resulting in
improved fault tolerance and network uptime.
• Equal-cost routing for load balancing and redundancy.
• Bandwidth aggregation up to 16 Gbps through 10 Gigabit Etherchannel
technology, 8 Gbps through Gigabit EtherChannel technology, and up to
800 Mbps through Fast EtherChannel technology enhances fault tolerance
and offers higher-speed aggregated bandwidth between switches and to
routers and individual servers.
• Uplink bandwidth can be easily upgraded by adding a 10 Gigabit Ethernet
version to a wiring closet stack and replace the one Gigabit Ethernet uplinks
with 10 Gigabit Ethernet without having to change fiber pairs.
High-performance IP Routing • Cisco Express Forwarding hardware routing architecture delivers extremely
high-performance IP routing.
• Basic IP unicast routing protocols (static, Routing Information Protocol Version 1
[RIPv1], and RIPv2) are supported for small-network routing applications.
• IPv6 routing support in hardware for maximum performance in the future.
• Advanced IP unicast routing protocols (Open Shortest Path First [OSPF], Interior
Gateway Routing Protocol [IGRP], Enhanced IGRP [EIGRP], and Border Gateway
Protocol Version 4 [BGPv4]) are supported for load balancing and constructing
scalable LANs. Enhanced Multilayer Software Image (EMI) is required.
• Policy-based routing (PBR) allows superior control by enabling flow redirection
regardless of the routing protocol configured. EMI is required.
• Hot Standby Routing Protocol (HSRP) provides dynamic load balancing and
failover for routed links, up to 32 HSRP links supported per unit or stack.
• Inter-VLAN IP routing for full Layer 3 routing between 2 or more VLANs.
• Protocol-Independent Multicast (PIM) for IP multicast routing is supported,
including PIM sparse mode (PIM-SM), PIM dense mode (PIM-DM), and PIM
sparse-dense mode. EMI is required.
• Distance Vector Multicast Routing Protocol (DVMRP) tunneling interconnects 2
multicast-enabled networks across non-multicast networks. EMI is required.
• Fallback bridging forwards non-IP traffic between 2 or more VLANs. EMI
is required.
• Routing is enabled across the stack.
• 128 switch virtual interfaces (SVIs) are recommended. Maximum of 1000 are
supported. (depends on the number of routes and multicast entries). 468 routed
ports are supported per stack.
Table 1
Product Features and Benefits (Continued)
Feature Benefit

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Integrated Cisco IOS Software
Features for Bandwidth
Optimization
• Per-port broadcast, multicast, and unicast storm control prevents faulty end
stations from degrading overall systems performance.
• IEEE 802.1d Spanning Tree Protocol support for redundant backbone
connections and loop-free networks simplifies network configuration and
improves fault tolerance.
• PVST+ allows for Layer 2 load sharing on redundant links to efficiently utilize the
extra capacity inherent in a redundant design.
• IEEE 802.1s Multiple Spanning Tree Protocol (MSTP) allows a spanning-tree
instance per VLAN, enabling Layer 2 load sharing on redundant links.
• Equal-cost routing for Layer 3 load balancing and redundancy across the stack.
EMI is required.
• Local Proxy Address Resolution Protocol (ARP) works in conjunction with Private
VLAN Edge to minimize broadcasts and maximize available bandwidth.
• VLAN1 minimization allows VLAN1 to be disabled on any individual VLAN
trunk link.
• VLAN Trunking Protocol (VTP) pruning limits bandwidth consumption on VTP
trunks by flooding broadcast traffic only on trunk links required to reach the
destination devices.
• Internet Group Management Protocol (IGMP) snooping provides fast client joins
and leaves of multicast streams and limits bandwidth-intensive video traffic to
only the requestors.
• Multicast VLAN Registration (MVR) continuously sends multicast streams in a
multicast VLAN while isolating the streams from subscriber VLANs for
bandwidth and security reasons.
• Up to 12 EtherChannel groups are supported per stack.
Scalable Stacking • Cisco StackWise stacking creates a 32 Gbps backplane. Stacking does not require
user ports. Up to 9 units can be stacked together for a maximum of 468 10/100
ports, 252 10/100/1000 ports, 108 optical aggregation ports, 9 10 Gigabit Ethernet
ports,or any mix thereof.
QoS/Control
Advanced QoS • Cross-stack QoS allows QoS to be configured across the entire stack.
• 802.1p class of service (CoS) and Differentiated Services Code Point (DSCP) field
classification are provided, using marking and reclassification on a per-packet
basis by source and destination IP address, source and destination Media Access
Control (MAC) address, or Layer 4 Transmission Control Protocol/User Datagram
Protocol (TCP/UDP) port number.
• Cisco control-plane and data-plane QoS ACLs on all ports ensure proper marking
on a per-packet basis.
• 4 egress queues per port enable differentiated management of up to 4 traffic
types across the stack.
• Shaped Round Robin (SRR) scheduling ensures differential prioritization of
packet flows by intelligently servicing the ingress queues and egress queues.
• Weighted Tail Drop (WTD) provides congestion avoidance at the ingress and
egress queues before a disruption occurs.
• Strict priority queuing guarantees that the highest-priority packets are serviced
ahead of all other traffic.
• There is no performance penalty for highly granular QoS functionality.
Table 1
Product Features and Benefits (Continued)
Feature Benefit

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Granular Rate Limiting • Cisco Committed Information Rate (CIR) function guarantees bandwidth in
increments as low as 8 Kbps.
• Rate limiting is provided based on source and destination IP address, source and
destination MAC address, Layer 4 TCP/UDP information, or any combination of
these fields, using QoS ACLs (IP ACLs or MAC ACLs), class maps, and policy
maps.
• Asynchronous data flows upstream and downstream from the end station or
on the uplink are easily managed using ingress policing and egress shaping.
• Up to 64 aggregate or individual policers are available per Fast Ethernet or
Gigabit Ethernet port.
Security
Network-wide Security
Features
• IEEE 802.1x allows dynamic, port-based security, providing user authentication.
• IEEE 802.1x with VLAN assignment allows a dynamic VLAN assignment for a
specific user regardless of where the user is connected.
• IEEE 802.1x with voice VLAN permits an IP phone to access the voice VLAN
irrespective of the authorized or unauthorized state of the port.
• IEEE 802.1x and port security are provided to authenticate the port and manage
network access for all MAC addresses, including that of the client.
• IEEE 802.1x with an ACL assignment allows for specific identity-based security
policies regardless of where the user is connected.
• IEEE 802.1x with Guest VLAN allows guests without 802.1x clients to have
limited network access on the Guest VLAN.
• Cisco security VLAN ACLs (VACLs) on all VLANs prevent unauthorized data flows
to be bridged within VLANs.
• Cisco standard and extended IP security Router ACLs (RACLs) define security
policies on routed interfaces for control-plane and data-plane traffic.
• Port-based ACLs (PACLs) for Layer 2 interfaces allow security policies to be
applied on individual switch ports.
• Secure Shell (SSH) Protocol, Kerberos, and Simple Network Management
Protocol Version 3 (SNMPv3) provide network security by encrypting
administrator traffic during Telnet and SNMP sessions. SSH, Kerberos, and the
cryptographic version of SNMPv3 require a special cryptographic software
image due to U.S. export restrictions.
• Private VLAN Edge provides security and isolation between switch ports, which
helps ensure that users cannot snoop on other users’ traffic.
• Bidirectional data support on the Switched Port Analyzer (SPAN) port allows
Cisco Secure Intrusion Detection System (IDS) to take action when an intruder
is detected.
Table 1
Product Features and Benefits (Continued)
Feature Benefit

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• Terminal Access Controller Access Control System Plus (TACACS+) and Remote
Authentication Dial-In User Service (RADIUS) authentication enable centralized
control of the switch and restrict unauthorized users from altering the
configuration.
• MAC address notification allows administrators to be notified of users added to
or removed from the network.
• DHCP Snooping allows administrators to ensure consistent mapping of IP to
MAC addresses. This can be used to prevent attacks which attempt to poison
the DHCP binding database, and to rate-limit the amount of DHCP traffic enters
a switch port.
• Port security secures the access to an access or trunk port based on
MAC address.
• After a specific timeframe, the aging feature removes the MAC address from
the switch to allow another device to connect to the same port.
• Trusted boundary provides the ability to trust the QoS priority settings if an IP
phone is present and to disable the trust setting in the event that the IP phone
is removed, thereby preventing a malicious user from overriding prioritization
policies in the network.
• Multilevel security on console access prevents unauthorized users from altering
the switch configuration.
• The user-selectable address-learning mode simplifies configuration and
enhances security.
• Bridge Protocol Data Unit (BPDU) guard shuts down Spanning-Tree Protocol
PortFast-enabled interfaces when BPDUs are received to avoid accidental
topology loops.
• Spanning Tree Root Guard (STRG) prevents edge devices not in the network
administrator’s control from becoming Spanning Tree Protocol root nodes.
• IGMP filtering provides multicast authentication by filtering out non-subscribers
and limits the number of concurrent multicast streams available per port.
• Dynamic VLAN assignment is supported through implementation of VLAN
Membership Policy Server (VMPS) client functionality to provide flexibility
in assigning ports to VLANs. Dynamic VLAN enables the fast assignment of
IP addresses.
• Cisco CMS Software security wizards ease the deployment of security features
for restricting user access to a server as well as to a portion or all of the network.
• 1000 access control entries (ACEs) are supported.
Table 1
Product Features and Benefits (Continued)
Feature Benefit

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Manageability
Superior Manageability • Cisco IOS CLI support provides common user interface and command set with
all Cisco routers and Cisco Catalyst desktop switches.
• Service Assurance Agent support facilitates service-level management
throughout the LAN.
• Switching Database Manager templates for access, routing, and VLAN
deployment scenarios allow the administrator to easily maximize memory
allocation to the desired features based on deployment-specific requirements.
• VLAN trunks can be created from any port, using either standards-based 802.1Q
tagging or the Cisco Inter-Switch Link (ISL) VLAN architecture.
• Up to 1005 VLANs per switch or stack and up to 128 spanning-tree instances
per switch are supported.
• 4000 VLAN IDs are supported.
• Voice VLAN simplifies telephony installations by keeping voice traffic on a
separate VLAN for easier administration and troubleshooting.
• Cisco VLAN Trunking Protocol (VTP) supports dynamic VLANs and dynamic
trunk configuration across all switches.
• Cisco Group Management Protocol (CGMP) server functions enable a switch
to serve as the CGMP router for CGMP client switches. EMI is required.
• IGMP snooping provides fast client joins and leaves of multicast streams and
limits bandwidth-intensive video traffic to only the requestors.
• Remote Switch Port Analyzer (RSPAN) allows administrators to remotely
monitor ports in a Layer 2 switch network from any other switch in the same
network.
• For enhanced traffic management, monitoring, and analysis, the Embedded
Remote Monitoring (RMON) software agent supports 4 RMON groups (history,
statistics, alarms, and events).
• Layer 2 traceroute eases troubleshooting by identifying the physical path that
a packet takes from source to destination.
• All 9 RMON groups are supported through a SPAN port, which permits traffic
monitoring of a single port, a group of ports, or the entire stack from a single
network analyzer or RMON probe.
• Domain Name Services (DNS) provide IP address resolution with user-defined
device names.
• Trivial File Transfer Protocol (TFTP) reduces the cost of administering software
upgrades by downloading from a centralized location.
• Network Timing Protocol (NTP) provides an accurate and consistent timestamp
to all intranet switches.
• Multifunction LEDs per port for port status; half-duplex and full-duplex mode;
and 10BASE-T, 100BASE-TX, and 1000BASE-T indication as well as switch-level
status LEDs for system, redundant-power supply, and bandwidth utilization
provide a comprehensive and convenient visual management system.
• SPAN works across all the ports in a stack.
Table 1
Product Features and Benefits (Continued)
Feature Benefit