Cisco Catalyst 4000 Series Switches

Catalyst 4912G Dedicated Gigabit Ethernet Aggregator


Data Sheet

Catalyst 4912G Dedicated Gigabit Ethernet Aggregator


The Catalyst® 4912G is a 12-port dedicated Gigabit Ethernet switch featuring high-performance Layer 2 switching and intelligent Cisco IOS® network services for high-speed network aggregator. The Catalyst 4912G is the flagship product of the new Catalyst 4900 Series, which delivers fixed configuration enterprise platforms providing cost-effective, high-performance solutions for Gigabit networking. The Catalyst 4912G switch provides an advanced enterprise switching solution delivering low-cost, high-density gigabit aggregation with modular Gigabit Interface Converter (GBIC) modular protection. The Catalyst 4912G switch provides intelligent Cisco IOS network services, capable of enhancing LAN scalability, multicasting, security, management, and quality of service (QoS). The dedicated gigabit Catalyst 4912G leverages the same feature set with identical software code base and the same enterprise functionality as the Catalyst 5000 Family, delivering a consistent end-to-end solution.

The Catalyst 4000 Family benefits include:

  • Powerful wire-speed performance with 24 Gbps of dedicated bandwidth for nonblocking Gigabit Ethernet concentration

  • Consistent and mature Catalyst 5000 Family software compatibility

  • Future-proof bandwidth protection with broad Gigabit EtherChannel® availability

  • GBIC flexibility on fiber port interfaces covering a wide range of cabling distances

  • Redundant, hot-swappable external power supply (option) and other fault-tolerant features

The Catalyst 4900 Series fixed-configuration gigabit solutions extend and advance the rich Ethernet heritage pioneered by the popular Catalyst 2900 10/100 switches. The Catalyst 4912G leverages the powerful hardware switching fabric (ASICs) of the modular Catalyst 4000 switch Family, plus offers the low entry-cost benefit of a fixed configuration form factor. The Catalyst 4912G broadens the Cisco Gigabit product offering, underscoring a continued investment in expanding the scope of Gigabit Ethernet solutions and further reducing the price-per-port of leading Gigabit solutions (now under $1350 per port list).

The Cisco Catalyst solution, provides a greater breadth and depth of switching solutions than ever before to meet your entire network's needs.

Figure 1: Catalyst 4912G Dedicated Gigabit Switch

Introducing the Catalyst 4912G Gigabit Aggregator

  • Dedicated 12-port 1000-Mbps Gigabit Ethernet for nonblocking high-speed switching—the Catalyst 4912G is a fixed configuration Layer 2 Ethernet switch with 12 Gigabit Ethernet ports. It was designed to easily handle the most demanding network bandwidth situations with intelligent EtherChannel® technology that scales to 8 Gbps. The Catalyst 4912G supports a high-performance architecture with nonblocking 24 Gbps total capacity; more than 18 million pps throughput; 16,000 MAC addresses; and 1024 Virtual LANs (VLANs).

  • Flexible, full-Duplex gigabit uplinks—each Catalyst 4912G comes standard with 12 gigabit uplink ports that can be configured with a variety of different interfaces depending upon the customer's network requirements. Utilizing advanced GBIC technology, customers can choose either shortwave (1000BaseSX) or longwave (1000BaseLX/LH) gigabit interfaces depending on network configuration requirements. And if, in the future, the customer's gigabit interface requirement changes, they can easily (and inexpensively) change their GBICs. (Note that GBICs are sold separately from the Catalyst 4912G.)

  • Industry-leading intelligent Catalyst system software—the Catalyst 4912G supports the full set of features found in enterprise Catalyst system software. Not only does this ensure interoperability with other Catalyst switches (such as the Catalyst 4000, 5000, and 6000 families), but it provides the Catalyst 4912G with the most comprehensive set of Layer 2 features available in the industry. Major software feature categories supported by the Catalyst 4912G include:

    • Advanced scalability (such as Gigabit EtherChannel, Dynamic VLANs, 802.1Q Trunking)

    • Bandwidth management (QoS, protocol filtering, link load balancing)

    • Network resiliency (UplinkFast, PortFast, spanning tree)

    • Security (per-port security, authentication, IP permit lists)

    • Advanced management (embedded RMON, SNMP, CiscoView, and CiscoWorks2000)

  • Small form factor Breakthrough—the Catalyst 4912G form factor continues the trend of power in a small package. The switch comes with a small footprint that is only 1.5 rack units high. The chassis is the exact same size as the popular Catalyst 2948G 10/100/1000 Mbps switch for rack or stack deployment.

  • Built-in fault tolerance—the Catalyst 4912G supports a variety of fault-tolerant features including an available external redundant power supply (sold separately and compatible with the popular Catalyst 2948G switches), support of multiple load sharing trunks (Gigabit EtherChannel), multiple spanning trees, and fast convergence software tools like PortFast and UplinkFast. This wide range of hardware and software fault-tolerant tools enable the Catalyst 4912G to provide the platform resiliency and fault tolerance required in today's mission- critical enterprise networks.

  • Comprehensive Network Management of CiscoWorks2000—Catalyst 4912G products are managed by the powerful CiscoWorks2000 network management products (option). These management products are focused on the day-to-day network operations functions such as:

    • Checking on device availability and configuration changes

    • Provisioning of VLANs across multiple devices concurrently

    • The representation of Layer 2 networks both physically and logically


The Catalyst 4912G is a cost-effective, high-performance, feature-rich, dedicated Gigabit Ethernet switch ideally suited for customers requiring Layer 2 switching for up to 12  1000-Mbps connections and links that scale to 8 Gbps. This new Catalyst switch has a nonblocking 24-Gbps architecture enabling all ports to operate simultaneously at wire speed. All 12 gigabit uplinks support standard GBIC technology enabling the customer to select and change gigabit interfaces in the Catalyst 4912G quickly, easily, and inexpensively. All interfaces scale intelligently with EtherChannel support.

The Catalyst 4912G features a dedicated configuration of 12 modular Gigabit Ethernet uplink ports. Fully integrated into the Catalyst family of switches, the Catalyst 4912G uses the same Catalyst system software as the industry-leading Catalyst 5000/5500 platforms, ensuring complete interoperability with existing Catalyst switches. The combination of high port density, wire-speed performance, rich software feature set, and affordable cost per port makes the Catalyst 4912G an excellent choice for high-speed network implementations.

Technical Specifications Catalyst 4912G

Standard Network Protocols

  • Gigabit Ethernet: IEEE 802.3z, IEEE 802.3x

  • 1000BaseX (GBIC)

    • 1000BaseSX

    • 1000BaseLX/LH

    • 1000BaseZX

  • VLAN trunking tagging: IEEE 802.1Q

  • Spanning Tree Protocol: IEEE 802.1D1000BaseX (GBIC)

Network Management

  • CiscoWorks2000 Network Management Suite, Resource Manager Essentials includes:

    • Inventory manager

    • Change audit

    • Device configuration manager

    • Software image manager

    • Availability manager

    • Syslog analyzer

    • Cisco management connection

  • CiscoWorks2000 Network Management Suite, CiscoWorks for Switched Internetworks (CWSI) campus includes:

    • Network topology discovery and display services

    • VLAN provisioning and logical display representation

    • Traffic monitoring and performance assessment

    • End-station tracking with search utilities

    • ATM and LANE service configuration and performance monitoring

    • CiscoView graphical device management

    • Network topology integrity checking

  • Cisco Discovery Protocol

  • Cisco Virtual Trunking Protocol (VTP)

  • Simple Network Management Protocol (SNMP) agent V.1 (RFCs 1155-1157)

  • SNMPV.2c

  • Cisco workgroup Management Information Base (MIB)

  • Ethernet MIB (RFC 1643)

  • Ethernet repeater MIB (RFC 1516)

  • SNMP MIB II (RFC 1213)

  • Remote Monitoring (RMON) (RFC 1757)

  • Remote Monitoring (RMON II) (RFC 2021)

  • Interface table (RFC 1573)

  • Bridge MIB (RFC 1493)

  • SMT 7.3 (RFC 1285)

  • Switched port analyzer (SPAN)

  • Enhanced switched port analyzer (ESPAN)

  • Port snooping and connection steering

  • Text-based command-line interface based on the familiar Catalyst 5000 interface

  • Standard Cisco IOS security capabilities: passwords and TACACS+

  • Telnet, Trivial File Transfer Protocol (TFTP), and BOOTP for management access


  • Gigabit EtherChannel: all 1000 Mbps ports

  • PAgP: Yes

Year 2000

  • Year 2000 compliant: Yes

Memory Specifications

  • Buffering: 8-MB Shared

  • NVRAM: 512 KB

  • FLASH: 12 MB

  • SDRAM: 64 MB

Switching Specifications

  • MAC addresses: 16,000

  • Virtual LANs (VLANs): 1,024

  • Fabric: store and forward

  • Queues: dual queuing

Indicators and Interfaces

Catalyst 4912G Switch

  • System status: green (operational)/red (faulty)

  • Switch Utilization load: 1- to 100-percent aggregate switching usage

  • Console (RJ-45 female)

  • Reset (switch recessed protected)

  • 10BaseT management (RJ-45 female) data terminal equipment (DTE): green (good)/orange (disabled)/off
    (not connected)

  • 12-ports Gigabit Ethernet with GBIC slot interfaces

    • Status: green (operational)/red (faulty)

Power Supply

  • PS1:

    • Good: green

    • Fail: red

  • RPS:

    • Good: green

    • Connected: amber (standing by)

    • Fail: red

  • SNMP MIB supported

Chassis Physical Specifications

  • Dimensions (H x W x D): 2-3/4 x 17.5 x 15 in.

  • 1.5 rack units (RU) high

  • Maximum weight: 13.5 lb (6.12 kg)

  • Mounting: 19-in. rack-compatible (rack hardware included)

Power Requirements

  • Input Current: 2.0A max. @ 100VAC 60Hz

   1.0A max. @ 200VAC 50Hz
  • KVA Rating: 0.20 KVA

  • Output power: 120 watts per power supply

  • Heat dissipation: 189 W(640 BTUs per hour)

  • Power factor correction: yes

Environmental Conditions

  • Operating temperature: 32 to 104° F (0 to 40° C)

  • Storage temperature: -40 to 167° F (-40 to 75° C)

  • Relative humidity: 10% to 90%, noncondensing

  • Operating altitude: -60 to 4000 m

Regulatory Compliance

  • CE Marking

  • UL 1950

  • CSA-C22.2 no 950

  • EN 60950, EN 609825

  • IEC 825

  • IEC 950

  • TS001

  • AS/NZ 3260

  • FCC 15J Class A, ICES-003 Class A, EN55022 Class A, CISPR22 Class A, AS/NZ 3584 Class A, VCCI Class A with UTP cables

  • EN 55022 Class B, CISPR22 Class B, AS/NZ 3548 Class B, VCCI Class B and BSIM Class B with FTP (foil twisted pair) cables