WS-C3850-12X48U-E Cisco Catalyst Switch, 48 Ports

Enterprise-Grade Cisco Catalyst 3850 Managed Switch

The Cisco WS-C3850-12X48U-E is a powerful Layer 3 managed switch designed for modern enterprise networks that demand high performance, scalability, and advanced power delivery. Built on the trusted Catalyst 3850 series, this model delivers exceptional throughput, flexible port configurations, and full support for Unified Power over Ethernet (UPOE).

General Specifications

Manufacturer Details

• Brand: Cisco
• Model / Part Number: WS-C3850-12X48U-E
• Product Type: Manageable Switch

Port Configuration

This managed switch features a versatile mix of high-speed and UPOE-enabled interfaces, making it ideal for bandwidth-intensive environments.

• 12 ports supporting 100 Mbps / 1G / 2.5G / 5G / 10G Ethernet
• 36 Gigabit Ethernet UPOE ports
• 1 network module expansion slot

Performance and Switching Capacity

Throughput and Forwarding

• Switching Capacity: Up to 480 Gbps
• Forwarding Rate: Approximately 357.14 Mpps

Scalability and Networking Features

• MAC address table supports up to 32,000 entries
• Up to 4,000 VLAN IDs for advanced network segmentation
• Supports both Layer 2 switching and Layer 3 routing

Power, Stacking, and Reliability

Power Supply and Input

• Single 1100W power supply unit
• AC input voltage range: 100–240V
• Operating frequency: 50–60 Hz

Stacking Capability

The Cisco Catalyst 3850 series supports switch stacking, allowing multiple units to operate as a single logical switch. This enhances redundancy, simplifies management, and increases overall network capacity.

Ideal Use Cases

• Enterprise campus networks
• High-density access layer deployments
• Organizations requiring UPOE for advanced devices
• Scalable environments needing robust Layer 3 switching

Deep Dive: Model WS-C3850-12X48U-E Specifications & Architecture

This model is a 1-Rack-Unit (1RU) managed switch that forms the backbone of modern, scalable networks. Its "12X48U" designation reveals its core hardware configuration: it boasts a total of 48 Ethernet ports, all of which support Cisco's Universal Power over Ethernet (UPoE), alongside 12 additional ports that are dedicated SFP/SFP+ slots for high-speed uplinks or stacking connections. The "-E" suffix signifies it is part of the "Essentials" tier in Cisco's licensing model, providing a robust set of Layer 3 routing and security features suitable for most enterprise deployments.

Hardware Components and Performance

At its heart, the Catalyst 3850 utilizes a programmable ASIC known as the "Unified Access Data Plane" (UADP), which enables feature parity between wired and wireless traffic and allows for future feature enhancements via software updates. The switch is equipped with a single, integrated power supply unit (PSU) in its base configuration, which is a critical consideration for power budgeting. The true power of this model lies in its UPoE capabilities on all 48 RJ-45 ports, each capable of delivering up to 60 watts of power per port (IEEE 802.3bt Class 4), with a total system power budget that supports simultaneous full UPoE across a significant portion of the ports. This makes it an ideal aggregation point for power-hungry devices like next-generation wireless access points (such as Cisco's 802.11ac Wave 2 and Wi-Fi 6 APs), PTZ cameras, thin clients, and building automation controllers.

Port Configuration Breakdown

48 x 10/100/1000BASE-T RJ-45 Ports: All ports support data rates of 10Mbps, 100Mbps, and 1Gbps. Crucially, each port is UPoE+ capable, providing up to 60W of power.
4 x 1G/10G SFP+ Uplink Ports: These four ports (often the first four of the twelve) support both 1 Gigabit and 10 Gigabit SFPs, providing flexible and high-bandwidth uplinks to the network core or to servers.
8 x Additional SFP Ports: The remaining eight slots support 1 Gigabit SFP modules. These can be used for additional fiber uplinks, or more importantly, for StackWise-480 connections.

Key Technologies and Features

The Cisco Catalyst 3850-12X48U-E is more than just a collection of ports; it is a feature-rich platform that addresses core challenges in scalability, resiliency, and network intelligence.

Cisco StackWise-480 Technology

This is a cornerstone feature for scalability and operational simplicity. StackWise-480 allows you to interconnect up to nine individual Catalyst 3850 switches to operate as a single, logical unit. The 12 SFP/SFP+ ports are used to create a 480 Gbps stacking ring using standard cabling (SFP+ cables). This "stack" behaves as one switch: it has a single management IP address, a unified configuration, and a shared routing table. This simplifies network design, reduces management overhead, and enables efficient use of uplinks. It also provides high resiliency; if one switch in the stack fails, the stack continues to operate, with automatic re-election of a master switch.

Unified Access & Embedded Wireless Controller

A defining characteristic of the Catalyst 3850 series is its convergence of wired and wireless management. The switch has an embedded wireless LAN controller (eWLC) that can manage up to 50 Cisco Aironet access points directly (depending on the software version and license). This eliminates the need for a separate physical WLC appliance in small to medium deployments or in branch offices, reducing cost and complexity. It enables a single point of policy enforcement for both wired and wireless clients, ensuring consistent security and quality of service (QoS) across the network.

Advanced Layer 3 Routing and Security

As a full Layer 3 switch, the WS-C3850-12X48U-E supports static routing, RIP, OSPF, EIGRP, and BGP routing protocols, allowing it to act as a routing boundary within the campus. Its security suite is comprehensive, including features like:

Cisco TrustSec: Provides software-defined segmentation using Security Group Tags (SGTs) to enforce policies based on user identity, not just IP address.
Advanced Malware Protection (AMP): When integrated with Cisco's threat intelligence, it can detect, block, and track malware across the network.
Network Access Control (NAC): Through integration with Cisco Identity Services Engine (ISE), it enables dynamic, policy-based access control for users and devices.
MACsec Encryption: Offers hop-by-hop encryption at Layer 2 for all traffic on a port, ensuring data confidentiality between switches.

Deployment Scenarios and Use Cases

The high-density UPoE and flexible uplinks make this switch model exceptionally versatile for a range of enterprise environments.

Enterprise Campus Wiring Closet

This is the classic deployment scenario. The Catalyst 3850-12X48U-E serves as the access layer switch for a floor or building, connecting end-user devices, IP phones, and wireless access points. Its UPoE capability powers all these devices seamlessly. Its Layer 3 functionality allows for routing at the edge, reducing the load on core switches. When stacked with other 3850s, it creates a highly resilient and easily managed access block.

Mid-Sized Network Core / Aggregation Layer

For smaller campuses or branch offices, a stack of Catalyst 3850 switches, particularly with their 10G SFP+ uplinks and powerful routing capabilities, can effectively serve as the network core or aggregation layer. They can aggregate traffic from multiple access switches, perform inter-VLAN routing, and connect to WAN routers and data center switches.

High-Density Wireless Deployment Hub

In environments with intensive wireless coverage needs—such as universities, large offices, or hospitals—this switch excels. Its ability to deliver UPoE to 48 ports simultaneously means it can power a large number of advanced, multi-radio wireless access points without requiring external power injectors. The embedded wireless controller functionality consolidates the network infrastructure into a streamlined, easy-to-manage platform.

IoT and Digital Building Convergence

The robust UPoE budget is perfect for the Internet of Things (IoT). The switch can power and network a diverse array of building systems—lighting controllers, HVAC sensors, security cameras, digital signage, and access control systems—all over standard Ethernet cabling. This convergence onto a single IP network simplifies installation, management, and data collection for smart building initiatives.

Software and Management

The switch runs Cisco's IOS-XE operating system, a modern, modular OS that provides greater stability, serviceability, and programmability compared to traditional IOS. Management can be performed via the familiar Cisco IOS Command-Line Interface (CLI), a web-based GUI (Device Manager), or through network management systems like Cisco DNA Center or Prime Infrastructure.

Understanding the "Essentials" License (E)

The -E in the model name refers to the pre-installed "IP Base" or "Network Essentials" license tier (terminology varies by IOS-XE version). This tier includes:

Advanced Layer 3 routing (static, RIPv2, OSPF, EIGRP stub). Standard security features (ACLs, port security, DHCP snooping).
Basic wireless controller functionality for a limited number of APs.

For more advanced features like full BGP routing, advanced WLC capabilities for more APs, or Cisco DNA Software-Defined Access (SDA), an upgrade to the "Advantage" license tier is required.

Power Considerations and Single PSU Note

The base model comes with a single, fixed AC power supply. It is crucial to calculate the total power draw of all connected PoE devices against the switch's total PoE budget and the capacity of this single PSU. For mission-critical deployments where power redundancy is required, organizations often plan for either:

Utilizing the switch in a StackWise configuration, where other switches in the stack can provide redundancy. Purchasing a model with dual, hot-swappable power supplies, or exploring field-upgrade options for a redundant PSU, if available for this specific SKU.

Comparison and Considerations

When evaluating the WS-C3850-12X48U-E, it's important to consider it within the broader Catalyst switching portfolio.

Catalyst 3850 vs. Catalyst 3650

The Catalyst 3650 is a similar, but slightly less powerful, stackable access switch. Key differences often include a lower stacking bandwidth (StackWise-160), a potentially lower PoE budget, and different licensing bundles. The 3850 is generally positioned for higher-performance, more scalable, and more feature-rich deployments.

Catalyst 3850 vs. Catalyst 9300

The Catalyst 9300 Series is the successor to the 3850, built on the newer Cisco UADP ASIC 3.0. The C9300 offers higher performance, greater scalability for encrypted traffic, full programmability with model-driven programmability and APIs, and is the foundational platform for Cisco's Software-Defined Access (SDA). For new deployments, Cisco typically recommends the Catalyst 9300. However, the 3850 remains a supremely capable and cost-effective solution, especially in environments not immediately planning an SDA transition.