WS-C3750X-24P-L Cisco 24 Port PoE Switch

Exploring the Cisco WS-C3750X-24P-L Catalyst 3750-X Switch

The Cisco WS-C3750X-24P-L represents a cornerstone of modular, stackable switching for enterprise access and distribution layer deployments. As a member of the revered Cisco Catalyst 3750-X Series, this switch delivers robust performance, enhanced security, and operational continuity in a flexible, forward-thinking form factor. Designed for business-critical networks, it combines high-density Gigabit Ethernet PoE+ connectivity with the intelligence of Cisco IOS Software, making it an ideal solution for powering IP phones, wireless access points, and connected devices while providing a resilient network foundation.

Core Architecture and Stacking Technology

At its heart, the WS-C3750X-24P-L is built for scalability and simplified management. Its architecture is defined by the innovative Cisco StackWise Plus technology, a fundamental differentiator for the 3750-X series.

Cisco StackWise Plus: The Virtual Backplane

StackWise Plus creates a unified, logical switching unit from up to nine individual switches connected via high-speed stack cables. This technology provides a resilient, ring-based 64 Gbps stacking interconnect that functions as a single virtual backplane.

Unified Management and Operation

From an operational standpoint, the entire stack is managed as a single entity. Administrators configure one IP address, one set of routing tables, and one set of QoS policies for the entire stack, dramatically reducing management overhead.

Stateful Switchover and Hitless Failover

StackWise Plus enhances availability with stateful switchover capabilities. In a stack with redundant stack masters, control plane protocols and network state are continuously synchronized, allowing for sub-second failover without dropping user sessions—a critical feature for voice and real-time applications.

Modular Power and Fan Tray Design

Unlike fixed-configuration switches, the 3750X series employs a modular design for both power supplies and fan trays. The WS-C3750X-24P-L ships with one internal 715W AC power supply, but its chassis supports the addition of a second, hot-swappable power supply for full hardware redundancy.

Flexible Power Supply Options

The switch accepts Cisco's range of field-replaceable power supplies, including AC, DC, and high-voltage AC models. This allows organizations to standardize on a switch model and later tailor the power infrastructure to specific deployment environments, such as data centers with DC plant or international offices with different voltage standards.

Field-Replaceable Fan Tray

The front-accessible, hot-swappable fan tray ensures consistent and quiet cooling. Its field-replaceable nature minimizes downtime in case of a fan failure, as the unit can be replaced without powering down the switch or the entire stack.

Technical Specifications and Performance Details

The Cisco WS-C3750X-24P-L is engineered to deliver wire-speed performance across all ports while providing the power and intelligence needed for modern converged networks. Its specifications are tailored for demanding access layer roles.

Port Configuration and Power over Ethernet Capabilities

The "24P" designation signifies 24 Ethernet 10/100/1000 ports with full Power over Ethernet Plus (PoE+) support. Additionally, the switch includes four Small Form-Factor Pluggable (SFP) based Gigabit Ethernet uplinks for fiber or copper connectivity.

Comprehensive PoE+ Budget

With its 715W power supply, the switch provides a substantial PoE power budget. It supports the IEEE 802.3at PoE+ standard, delivering up to 30 watts per port. This is sufficient to power a wide array of devices, from standard VoIP phones and basic access points to more demanding equipment like PTZ cameras, video phones, and thin clients.

Intelligent Power Management

Cisco's Intelligent Power Management (IPM) features allow for granular control over power allocation. Administrators can set power priorities per port, ensuring critical devices remain powered during a budget shortfall. The switch also supports Cisco Universal Power over Ethernet (UPOE), enabling the use of specialized modules for higher power delivery.

Uplink Flexibility with Network Modules

The four built-in SFP uplink ports offer baseline connectivity. However, the switch's true flexibility comes from its optional uplink module slot. This slot can accommodate various Cisco pluggable modules.

10 Gigabit Ethernet Uplink Module

The C3KX-NM-10G module adds two 10 Gigabit Ethernet SFP+ uplinks, providing high-bandwidth connectivity to the network core or aggregation layer, future-proofing the investment and alleviating potential uplink bottlenecks.

1 Gigabit Fiber Uplink Module

Alternative modules offer additional Gigabit Ethernet fiber ports, providing flexibility for diverse cabling infrastructures and longer-distance connections.

Switching Capacity and Forwarding Rates

The switch boasts a robust switching fabric with a total bandwidth of 160 Gbps. It is capable of a forwarding rate of up to 101.2 Mpps (million packets per second), ensuring wire-speed, non-blocking performance across all 24 Gigabit Ethernet ports and the uplinks, even under full-duplex conditions.

Advanced Software Features and Security

Powered by Cisco's full-featured IOS Software, the WS-C3750X-24P-L is more than just a simple connectivity hub. It is an intelligent network node capable of advanced routing, security, and traffic management.

Comprehensive Security Suite

In today's threat landscape, access layer security is paramount. The Catalyst 3750-X incorporates a multi-layered security architecture.

Network Foundation Protection

This Cisco strategy hardens the switch itself against attacks. It includes control plane policing (CoPP) to protect the CPU, secure management access via SSHv2, SNMPv3, and role-based access control (RBAC).

TrustSec and Access Control

Cisco TrustSec technology provides identity-aware networking. Using 802.1X authentication, the switch can identify users and devices and assign them to appropriate VLANs and security policies (Security Group Tags - SGTs), enabling micro-segmentation and consistent policy enforcement across the network.

Dynamic ARP Inspection and IP Source Guard

These features protect against common Layer 2 attacks like ARP spoofing and IP address theft, ensuring traffic flows only from legitimate sources.

Advanced Quality of Service (QoS)

For converged networks carrying voice, video, and data, intelligent traffic handling is essential. The switch provides extensive QoS features.

Auto-QoS for Simplified Deployment

The Auto-QoS feature simplifies configuration by automatically detecting voice or video traffic (e.g., from a Cisco IP Phone) and applying optimized QoS settings, reducing complexity for administrators.

Layer 3 Routing Capabilities

The "IP Lite" or "IP Services" feature sets (depending on software image) provide dynamic routing functionality. The switch can perform inter-VLAN routing and run routing protocols like RIP, OSPF, and EIGRP for small to medium-sized networks, allowing it to function effectively in a collapsed core or distribution layer role.

Deployment Scenarios and Use Cases

The versatility of the Cisco WS-C3750X-24P-L makes it suitable for a wide range of enterprise environments, from corporate offices to educational campuses.

Enterprise Wiring Closet / Access Layer

This is its primary deployment scenario. In a typical office floor, the switch connects end-user devices, providing PoE to phones and wireless access points, enforcing security policies, and segregating traffic into VLANs. Its stacking capability allows a network closet to scale port density seamlessly.

Branch Office Aggregation

In a regional or branch office, a stack of 3750X switches can serve as the complete network infrastructure, handling both access and routing duties. The Layer 3 capabilities allow for local routing between departments and WAN connectivity back to the head office.

Mid-Sized Business Core

For small to mid-sized businesses, a stack of high-performance 3750X switches with 10G uplinks can form a resilient and capable network core, providing connectivity between access switches, servers, and the internet edge.

High-Density Wireless Deployment

In environments with dense Wi-Fi coverage, such as lecture halls or conference centers, the switch's high PoE+ budget and 10G uplink options are ideal for powering multiple, high-performance Cisco wireless access points and backhauling their traffic efficiently.