Cisco Catalyst 4948 User Manual

Data Sheet

Cisco Catalyst 4948 Switch

1

High-Performance, Rack-Optimized Server Switching

Product Overview

The Cisco Catalyst® 4948 Switch is a wire-speed, low-latency, Layer 2 to 4, 1-rack-unit (1RU), fixed-configuration switch for rack-optimized server switching. Based on the proven Cisco® Catalyst 4500 Series hardware and software architecture, the Cisco Catalyst 4948 offers exceptional performance and reliability for low-density, multilayer aggregation of high-performance servers and workstations. High performance and scalability of intelligent network services is made possible with dedicated specialized resources known as ternary content addressable memory (TCAM). Ample TCAM resources (64,000 entries) enable high feature capacity, providing wire-speed routing and switching performance with concurrent provisioning of services such as quality of service (QoS) and security, and helping ensure scalability for today's network requirements with ample room for future growth.

The Cisco Catalyst 4948 offers 48 ports of wire-speed 10/100/1000BASE-T with four alternative wired ports that can accommodate optional 1000BASE-X Small Form-Factor Pluggable (SFP) optics.1 Exceptional reliability and serviceability are delivered with optional internal AC or DC 1+1 hot-swappable power supplies and a hot-swappable fan tray with redundant fans (Figures 1 and 2).

Figure 1. Cisco Catalyst 4948 Switch

Figure 2. Rear View of Cisco Catalyst 4948 with Dual Redundant Power Supplies and Removable Fan Tray

The Cisco Catalyst 4948 has 52 physical switching ports (48 10/100/1000 and 4 SFP) on the front panel. Up to 48 of these ports

can be active at one time in any combination.

Data Sheet

Features and Benefits

Wire-Speed Performance for 10/100/1000 Connectivity

The Cisco Catalyst 4948 delivers wire-speed throughput with low latency for data-intensive applications, using a 96Gbps switching fabric with a forwarding rate of 72 million packets per second (mpps) in hardware for Layer 2 to 4 traffic. Switching performance remains high regardless of the number of route entries or Layer 3 and 4 services enabled. Hardware-based Cisco Express Forwarding routing architecture enables increased scalability and performance.

Power Supply Redundancy for Nonstop Operation

The Cisco Catalyst 4948 provides reliability for critical applications, with 1+1 redundant hot-swappable internal AC or DC power supplies. The 1+1 power supply design provides A-to-B failover when power supplies are connected to different circuits. AC and DC power supplies can be mixed in the same unit for outstanding deployment flexibility. The Cisco Catalyst 4948 also has a hot-swappable fan tray with four redundant fans for additional serviceability and availability.

Wire-Speed Performance for 10/100/1000 Connectivity

The Cisco Catalyst 4948 delivers wire-speed throughput with low latency for data-intensive applications, using a 96Gbps switching fabric with a forwarding rate of 72 million packets per second (mpps) in hardware for Layer 2 to 4 traffic. Switching performance remains high regardless of the number of route entries or Layer 3 and 4 services enabled. Hardware-based Cisco Express Forwarding routing architecture enables increased scalability and performance.

Power Supply Redundancy for Nonstop Operation

The Cisco Catalyst 4948 provides reliability for critical applications, with 1+1 redundant hot-swappable internal AC or DC power supplies. The 1+1 power supply design provides A-to-B failover when power supplies are connected to different circuits. AC and DC power supplies can be mixed in the same unit for outstanding deployment flexibility. The Cisco Catalyst 4948 also has a hot-swappable fan tray with four redundant fans for additional serviceability and availability.

Comprehensive Management

The Cisco Catalyst 4948 includes a single, dedicated 10/100 console port and a single, dedicated 10/100 management port for offline disaster recovery. Remote in-band management is available with the Simple Network Management Protocol (SNMP), Telnet client, Bootstrap Protocol (BOOTP), and Trivial File Transfer Protocol (TFTP). Support for local or remote out-of-band management is delivered through a terminal or modem attached to the console interface. The management port helps enable the Cisco Catalyst 4948 to reload a new image from a TFTP server within seconds.

The Cisco Catalyst 4948 delivers a comprehensive set of management tools to provide the visibility and control required for server switching. Managed with CiscoWorks solutions and embedded CiscoWorks CiscoView, the Cisco Catalyst 4948 can be configured and managed to deliver device, VLAN, traffic, and policy management. These webbased management tools offer numerous services, including software deployment and quick isolation of error conditions.

Software Configuration Options

Table 1 summarizes the software configuration options for the Cisco Catalyst 4948.

Data Sheet

Software Image

Description

LAN Base image

Basic Layer 2 image

IP Base image

Standard Layer 3 image, including Routing Information Protocol Version 1 (RIPv1), RIPv2, static routes, and Enhanced Interior Gateway Routing Protocol (EIGRP) stub

Enterprise Services image

Enhanced Layer 3 image, including Open Shortest Path First (OSPF), Intermediate System–to–Intermediate System (IS-IS), EIGRP, Border Gateway Protocol (BGP), AppleTalk, and Internetwork Packet Exchange (IPX) software routing; also includes all IP Base image features

Feature and Description

Cisco Catalyst 4948

Cisco Catalyst 4948 10 Gigabit Ethernet

Cisco Catalyst 4900M

Switching capacity

96 Gbps

136 Gbps

320 Gbps

Throughput

72 mpps

102 mpps

●

250 mpps for IPv4

●

125 mpps for IPv6

IPv6 support

In software

In hardware

Height

1RU

2RU

Modular half-card slots

0 0 2

Maximum 10/100/1000 ports

48

40

Maximum 10 Gigabit Ethernet ports

0 2 24

Maximum Gigabit Ethernet (fiber) ports

4 0 32 (Cisco TwinGig Converter Module)

Cisco TwinGig Converter Module support

No

Yes (half-cards only)

Uplink optic type

4 SFP optics

2 X2 (10 Gigabit Ethernet) optics

8 X2 (10 Gigabit Ethernet) optics

Multilayer switching

IP Base and Enterprise Services options

Shared buffer

16 MB

CPU

266 MHz

666 MHz

1.3 GHz

Synchronous Dynamic RAM (SDRAM)

256 MB

512 MB

Active VLANs

4096

Multicast entries

●

28,000 (Layer 3)

●

16,000 (Layer 2)

●

28,000 (Layer 3)

●

16,000 (Layer 2)

●

56,000 for IPv4

●

28,000 for IPv6

Per-VLAN Spanning Tree (PVST) and VLAN IDs

4096

Spanning Tree Protocol instances

1500

3000

Switched Virtual Interfaces (SVIs)

2000

4000

Security and QoS hardware entries

32,000

128,000

MAC addresses

32,000

55,000

Switched Port Analyzer (SPAN)

2 ingress and 4 egress

8 ingress and 8 egress

USB port

No

Yes

Compact flash memory support

No

Yes

System reset button

No

Yes

Minimum software requirement

Cisco IOS® Software Release

12.2(20)EWA or later

Cisco IOS Software Release

12.2(25)EWA or later

Cisco IOS Software Release

12.2(40)XO or later

Table 1. Software Configuration Options for Cisco Catalyst 4948

Feature Comparison

Table 2 compares the features of the Cisco Catalyst 4948 Switch, Catalyst 4948 10 Gigabit Ethernet Switch, and Catalyst 4900M Switch.

Table 2. Cisco Catalyst 4900 Series Switches Model Comparison

Data Sheet

Features and Specifications at a Glance

Performance and Switching

●

96 Gbps nonblocking switch fabric

●

72 mpps Layer 2 forwarding (hardware)

●

72 mpps Layer 3 and 4 forwarding: IP routing and Cisco Express Forwarding (hardware)

●

Layer 2 to 4 hardware-based switch engine (application-specific integrated circuit [ASIC]-based)

●

Unicast and multicast routing entries: 32,000

●

Support for 4096 active VLANs and 4096 VLAN IDs per switch

●

Layer 2 multicast addresses: 16,384

●

MAC addresses: 32,768

●

Policers: 512 ingress and 512 egress

●

Access control list (ACL) and QoS entries: 32,000

●

Uplinks: 4 alternatively wired SFP ports with Cisco Gigabit EtherChannel support

●

Latency: 6 microseconds for 64-byte packets

●

SVIs: 2048

●

Spanning Tree Protocol instances: 1500

●

Internet Group Management Protocol (IGMP) snooping entries: 16,000

Layer 2 Features

●

Layer 2 hardware forwarding at 72 mpps

●

Layer 2 switch ports and VLAN trunks

●

IEEE 802.1Q VLAN encapsulation

●

Inter-Switch Link (ISL) VLAN encapsulation

●

Dynamic Trunking Protocol (DTP)

●

VLAN Trunking Protocol (VTP) and VTP domains

●

PVST+ and Per-VLAN Rapid Spanning Tree Protocol (PVRST)

●

Flexlink

●

Spanning Tree PortFast and PortFast Guard

●

Spanning Tree UplinkFast and BackboneFast

●

IEEE 802.1s

●

IEEE 802.1w

●

IEEE 802.3ad

●

Spanning Tree Root Guard

●

Cisco Discovery Protocol Version 1 and 2

●

IGMPv1, v2, and v3

●

Cisco EtherChannel technology, Cisco Fast EtherChannel technology, and Cisco Gigabit EtherChannel technology support

●

Port Aggregation Protocol (PAgP)

●

Link Aggregation Control Protocol (LACP)

●

Unidirectional Link Detection Protocol (UDLD) and aggressive UDLD on the SFP ports

Data Sheet

●

IEEE 802.1 Q-in-Q in hardware

●

Layer 2 protocol tunneling

●

Jumbo frames on all ports (up to 9216 bytes)

●

Baby giants (up to 1600 bytes)

●

Unidirectional Ethernet

●

Hardware-based storm control (formerly known as broadcast and multicast suppression)

●

Community private VLANs (PVLANs)

●

Forced 10/100 autonegotiation

●

Web Cache Communication Protocol (WCCP) Version 2 Layer 2 redirect

●

Private VLAN promiscuous trunk

●

Layer 2 promiscuous trunk over trunk port (L2PT)

●

Class-of-service (CoS) mutation

●

E-OAM 802.3ah and CFM: 802.1ag

Layer 3 Features

●

Jumbo frames on all ports (up to 9216 bytes)

●

Hardware-based IP Cisco Express Forwarding routing at 72 mpps

●

Static IP routing

●

IP routing protocols: EIGRP, OSPF, RIP, and RIPv2

●

BGPv4 and Multicast Border Gateway Protocol (MBGP)

●

Nonstop Forwarding (NSF) awareness

●

Hot Standby Router Protocol (HSRP) v1 and v2

●

Software routing of IPX and AppleTalk

●

IS-IS routing protocol

●

IGMPv1, v2, and v3

●

IGMP filtering on access and trunk ports

●

IP multicast routing protocols: Protocol Independent Multicast (PIM), Source-Specific Multicast (SSM), and Distance Vector Multicast Routing Protocol (DVMRP)

●

Auto rendezvous point (Auto-RP)

●

Distance Vector Multicast Routing Protocol (DVMRP)

●

Pragmatic General Multicast (PGM)

●

Cisco Group Management Protocol (GMP) server

●

Full Internet Control Message Protocol (ICMP) support

●

ICMP Router Discovery Protocol

●

Policy-based routing (PBR)

●

Virtual Route Forwarding lite (VRF-lite)

●

VRF-aware IP services

●

IPv6 software switching support

●

OSPF fast convergence

●

OSPF and EIGRP fast-convergence protection

Data Sheet

●

EIGRP stub

●

Virtual Router Redundancy Protocol (VRRP)

●

IP unnumbered for SVI

●

Nonstop Forwarding (NSF) awareness

●

WCCPv2

●

Gateway Load Balancing Protocol (GLBP)

High-Availability Features

●

1+1 hot-swappable AC or DC power supplies

●

Hot-swappable field-replaceable fan tray with redundant fans

●

HSRP v1 and v2

●

VRRP

●

Cisco IOS Embedded Event Manager (EEM)

●

Cisco Generic Online Diagnostics (GOLD)

●

Smart Call Home

Sophisticated QoS and Traffic Management

●

Per-port QoS configuration

●

Per-port and per-VLAN QoS

●

Support for four queues per port in hardware

●

Strict priority queuing

●

IP differentiated services code point (DSCP) and IP precedence

●

Classification and marking based on IP type of service (ToS) or DSCP

●

Classification and marking based on full Layer 3 and 4 headers (IP only)

●

Input and output policing based on Layer 3 and 4 headers (IP only)

●

Support for 512 policers on ingress and 512 policers on egress configured as aggregate or individual

●

Shaping and sharing output queue management

●

Dynamic Buffer Limiting (DBL) advanced congestion-avoidance feature

●

No performance penalty for granular QoS functions

●

Matched CoS for non-IPv4 traffic

Predictable Performance

●

96-Gbps switching fabric

●

Layer 2 hardware forwarding at 72 mpps

●

Layer 3 hardware-based IP Cisco Express Forwarding routing at 72 mpps

●

Layer 4 TCP and User Datagram Protocol (UDP) hardware-based filtering at 72 mpps

●

No performance penalty with advanced Layer 3 and 4 services enabled

●

Software-based learning at a sustained rate of 500 hosts per second

●

Support for 32,768 MAC addresses

●

Support for 32,000 entries in routing table (shared between unicast and multicast)

●

Support for 512 ingress policers and 512 egress policers