WS-C3850-16XS-S Cisco Ethernet Switch (16 Ports)

Product Overview

The Cisco WS-C3850-16XS-S Catalyst 3850 is a high-performance 10 Gigabit fiber Ethernet switch designed for enterprise-grade networking environments. Built with advanced Layer 3 capabilities, this rack-mountable switch ensures reliable connectivity, scalability, and efficient network management for modern data centers and business infrastructures.

Main Specifications

General Details

• Brand: Cisco
• Model Number: WS-C3850-16XS-S
• Product Category: Ethernet Network Switch
• Switch Type: Non-modular
• Stacking Capability: Supported

Network Performance

• Ethernet Standard: 10 Gigabit Ethernet
• Network Technology: 10GBASE-X
• Supported Media: Optical Fiber
• Layer Support: Layer 3 (L3 Switching)

Key Features and Capabilities

Port and Expansion Options

High-Speed Connectivity

• Total Expansion Slots: 12
• Expansion Slot Type: SFP+
• Number of SFP+ Ports: 12
• 10 Gigabit Ethernet Fiber Ports for ultra-fast data transfer

Management and Control

Advanced Network Administration

• Fully manageable switch for centralized network control
• Optimized for enterprise switching and routing tasks
• Supports scalable and secure network architectures

Power and Reliability

Power Configuration

Enhanced Uptime and Redundancy

• Primary Power Source: Power Supply Unit
• Redundant Power Supply: Supported
• Designed to minimize downtime in mission-critical networks

Physical Design

Form Factor

• Rack-Mountable Design
• Compatible Rack Size: 1U
• Ideal for data centers, server rooms, and enterprise racks

Deep Dive: WS-C3850-16XS-S Hardware Specifications

This specific variant is built for scenarios demanding extreme throughput and low latency. Its hardware profile is tailored for modern data centers, high-performance computing clusters, and aggregation layers.

Port Configuration and Uplinks

The "16XS" in the model number denotes 16 fixed 10 Gigabit Ethernet SFP+ ports. These ports provide immense flexibility:

Fiber Optic Connectivity: Using SFP+ modules, they support long-reach fiber connections (single-mode or multimode), ideal for backbone links, server farm access, and inter-switch links (ISL).
10GBase-T Copper Option: With appropriate SFP+ transceivers, they can also connect via Cat6a/Cat7 copper cabling for short-reach 10GbE connections to servers or other switches.
Stacking Role: These ports are dual-purpose. They serve as high-speed data ports and, crucially, as the StackWise-480 stacking ports, creating a resilient, logical single switch from multiple physical units.

Performance and Architecture

Underneath the sleek exterior lies a powerful switching engine designed for non-blocking performance.

Switching Capacity and Forwarding Rate

The switch delivers a substantial aggregate switching capacity of 480 Gbps across its backplane. With a forwarding rate of up to 357 Mpps (million packets per second), it can handle massive amounts of data and high packet rates without congestion, ensuring smooth performance for real-time applications like voice and video.

StackWise-480 Technology

This is a cornerstone feature. StackWise-480 allows up to nine Catalyst 3850 switches to be connected as a single logical entity. The stack uses a dedicated 480 Gbps ring connection, sharing control and data planes. Benefits include simplified management (one IP address), inter-switch link elimination, and high availability with sub-second failover.

Software and Feature Set

The "-S" suffix indicates the switch ships with the IP Base feature set. This provides a robust suite of Layer 2 and Layer 3 functionalities suitable for most enterprise access and distribution layer requirements.

Layer 2 Switching Capabilities

IP Base includes comprehensive switching features for building stable, loop-free, and efficient networks.

Advanced Spanning Tree Protocols

Supports PVST+, Rapid-PVST+, and MSTP (Multiple Spanning Tree Protocol) for robust loop prevention and fast convergence in complex topologies.

Virtual LAN (VLAN) Features

Full IEEE 802.1Q VLAN tagging support, VLAN Trunking Protocol (VTP) versions 1-3, and Private VLANs for enhanced security and segmentation within a broadcast domain.

EtherChannel and Link Aggregation

Supports both static EtherChannel and dynamic protocols (PAgP and LACP) to bundle multiple physical links into a single logical link for increased bandwidth and redundancy.

Layer 3 Routing Capabilities

While not the full "IP Services" suite, IP Base provides essential static and dynamic routing.

Routed Protocols

Full IPv4 and IPv6 unicast routing capability.

Dynamic Routing Protocols

Includes support for OSPF (Open Shortest Path First) and EIGRP (Enhanced Interior Gateway Routing Protocol) for IPv4. For IPv6, it supports OSPFv3 and EIGRP for IPv6. This allows the switch to function effectively as a distribution layer device, dynamically routing traffic between VLANs and to the network core.

Converged Access and Unified Wireless Network Management

The integration of a wireless LAN controller is a game-changer for environments deploying Cisco Aironet access points.

Benefits of Embedded Wireless Controller

By hosting the WLC functionality, the Catalyst 3850 eliminates the need for a separate physical wireless controller appliance for small to medium deployments.

Unified Policy and Configuration

Network policies for security, QoS, and access control are defined once and applied consistently to users and devices, whether they connect via an Ethernet port or a Wi-Fi access point.

Enhanced Visibility and Troubleshooting

Network administrators gain a single pane of glass for monitoring client health, performance, and connectivity across both domains, drastically simplifying troubleshooting.

Scalability

A single Catalyst 3850 switch can manage a specific number of access points (dependent on the software version and switch resources), scaling appropriately as part of a stack.

Quality of Service (QoS) and Security

In a converged network carrying data, voice, and video, intelligent traffic handling and robust security are non-negotiable.

Advanced QoS for Critical Applications

The switch supports sophisticated classification, marking, policing, shaping, and queuing mechanisms.

Classification and Marking

Can classify traffic based on Layer 2 (CoS), Layer 3 (DSCP), Layer 4 (TCP/UDP ports), and deep packet inspection. Trust boundaries can be established to preserve markings from IP phones or other trusted devices.

Queueing and Scheduling

Uses a hardware-based queuing system with strict priority and weighted round-robin (WRR) scheduling to ensure low-latency, jitter-sensitive traffic like VoIP is always prioritized.

Comprehensive Security Suite

The IP Base software includes a wide array of security features to protect the network infrastructure and its data.

Network Access Control

Supports IEEE 802.1X for port-based authentication, using RADIUS servers to validate user credentials before granting network access. Extensions like MAC Authentication Bypass (MAB) and Web Authentication provide flexibility for diverse device types.

Access Control Lists (ACLs)

Robust support for standard, extended, and named ACLs for both IPv4 and IPv6. Time-based ACLs allow security policies to be enforced according to a schedule.

Dynamic ARP Inspection (DAI) & IP Source Guard

These features work in tandem to prevent common layer-2 attacks like ARP spoofing and IP address spoofing, ensuring traffic originates from legitimate, verified sources.

Energy Efficiency and Manageability

The Catalyst 3850 is designed with operational costs and ease of management in mind.

Cisco EnergyWise Technology

This innovative feature enables network-wide energy management. The switch can monitor and control power consumption of connected devices (like IP phones, PoE access points, and even non-networked assets via smart power strips), helping organizations meet sustainability goals and reduce electricity costs.

Management Interfaces and Tools

The switch offers multiple avenues for configuration and monitoring.

Command-Line Interface (CLI)

The industry-standard Cisco IOS CLI, accessible via console, SSH, or Telnet, provides granular control for experienced network engineers.

Web-based Management

A built-in web interface (Cisco Device Manager) offers a graphical alternative for basic setup and monitoring.

Network Management Suites

Fully compatible with Cisco Prime Infrastructure and Cisco DNA Center for enterprise-scale automation, assurance, and software-defined access (SD-Access) capabilities when upgraded to appropriate software versions.

Ideal Deployment Scenarios for the WS-C3850-16XS-S

This switch is not a one-size-fits-all device; its strengths shine in specific environments.

Data Center Top-of-Rack (ToR) Switch

Its sixteen 10G SFP+ ports make it an excellent ToR switch for server racks, providing high-speed connectivity to servers equipped with 10GbE network interfaces, with ample bandwidth for east-west traffic and northbound uplinks.

Network Aggregation and Distribution Layer

In campus networks, it can aggregate traffic from multiple access switches (e.g., 1GbE or 10GbE uplinks) and provide intelligent routing, QoS, and security policies before handing off to the core. Its stacking capability allows the aggregation layer to grow seamlessly.

High-Performance Workgroup or Building Core

For smaller campuses or buildings with high-density, bandwidth-hungry users (engineering departments, multimedia labs), a stack of 3850-16XS switches can form a resilient, high-speed core and distribution layer in one.