Introduction to Cisco Switches | Generated by AI
Question: Can you give a comprehensive introduction to Cisco switches?
Answer:
Cisco Systems is the dominant player in enterprise networking, and their switching portfolio is one of the largest and most widely deployed in the world. Cisco switches range from small unmanaged devices for homes/SMBs to massive modular chassis switches that form the backbone of the largest data centers and service providers.
1. Cisco Switch Families (Current as of 2025)
| Series | Primary Use Case | Key Models (examples) | Form Factor | Key Features / Positioning |
|---|---|---|---|---|
| Catalyst 9000 | Enterprise campus & branch (flagship) | 9200/9300/9400/9500/9600 | Fixed & modular | Intent-based networking, Cisco DNA Center, Wi-Fi 6/6E/7 support, advanced security |
| Catalyst 8000 | Edge routing + switching | 8200/8300/8500 | Fixed | SD-WAN focus, high throughput routing |
| Catalyst 1000 | Small business / access layer | 1000-8P, 1000-24T | Fixed 8–48 port | Affordable, basic L2/L3, fanless options |
| Catalyst 1200/1300 | SMB & basic enterprise | 1200-8T, 1300-16P | Fixed | Successor to SF/SG series, modern IOS-XE Lite |
| Meraki MS | Cloud-managed switching | MS120, MS210, MS350, MS410, MS450 | Fixed & modular | 100% cloud dashboard, zero-touch provisioning |
| Nexus 9000 | Data center (ACI or NX-OS mode) | 9200/9300/9500/9600 | Fixed & modular | VXLAN/EVPN, 10/25/40/100/400/800G, programmable |
| Nexus 7000/7700 | Legacy high-end data center / core | 7004/7009/7010/7710 | Large modular chassis | Being phased out in favor of 9000 |
| Industrial Ethernet | Rugged environments (IE series) | IE-2000, IE-3000, IE-4000, IE-5000, IE-9300 | DIN-rail / rugged | Extended temp, vibration resistance, PROFINET, etc. |
| Catalyst 8000V / CSR1000v | Virtual switches/routers | Software only | VM / container | Runs on any hypervisor or cloud |
2. Operating Systems on Cisco Switches
| OS | Used On | Key Characteristics |
|---|---|---|
| Classic IOS | Older Catalyst (2950, 3560, 3750, etc.) | EOL in most cases |
| IOS-XE | All modern Catalyst 9000, 8000, 1000/1200 | Modular, separate control/data plane, In-Service Software Upgrade (ISSU) |
| IOS-XE Lite | Catalyst 1000/1200/1300 | Stripped-down version for SMB |
| NX-OS | Nexus series | Data-center focused, feature-rich CLI, ISSU, strong VXLAN/BGP-EVPN |
| Meraki Dashboard | Meraki MS switches | No local CLI (limited API/CLI now available), 100% cloud |
| ACI | Nexus 9000 in ACI mode | Application Centric Infrastructure – policy-driven, APIC controller |
3. Layer 2 vs Layer 3 Capabilities
- Almost all modern Cisco switches (Catalyst 9200 and above, Nexus, Meraki) are L2/L3 switches.
- Entry-level Catalyst 1000/1200 offer basic static routing or even full dynamic routing in higher SKUs.
- High-end models (9300/9400/9500, Nexus 9300/9500) support full routing tables, BGP, OSPF, EIGRP, MPLS, Segment Routing, etc.
4. Key Technologies & Features
| Feature | Description | Typical Series |
|---|---|---|
| StackWise / StackWise Virtual | Physical or logical stacking (up to 480 Gbps stack bandwidth on 9600) | Catalyst 9300/9500/9600 |
| Virtual Switching System (VSS) / Multichassis EtherChannel (MEC) | Older multi-chassis technology (largely replaced by StackWise Virtual) | 6500/6800, 9400/9600 |
| Cisco DNA Center / Catalyst Center | Intent-based networking, assurance, automation, telemetry | Catalyst 9000 |
| Encrypted Traffic Analytics (ETA) | Detect malware in encrypted traffic without decryption | Catalyst 9000 |
| Application Hosting (Docker/Kubernetes) | Run containers directly on the switch | 9300/9400/9500/9600 |
| 400G / 800G optics | Highest-density data center switching | Nexus 9300-EX/FX/GX/HX |
| MACsec & TrustSec | Link-layer encryption & SGT-based policy enforcement | Most Catalyst 9000 & Nexus |
| NetFlow / sFlow / Telemetry | Rich visibility | All modern platforms |
5. Licensing (Simplified – 2025)
Cisco moved to Cisco DNA Advantage / Premier (now largely rebranded to Cisco Catalyst Subscription or Cisco DNA Subscription for Switching):
- Network Essentials / Advantage → now Network Stack (perpetual) + optional Catalyst Subscription (3/5/7 years)
- Higher-tier subscription gives you DNA Center features, assurance, SD-Access, ISE integration, etc.
- Meraki is purely subscription (per switch, 1/3/5/7/10 years).
Nexus uses NX-OS Essentials / Advantage / Premier add-ons.
6. Typical Deployment Tiers (Campus)
- Access layer: Catalyst 9200 / 9300 or Meraki MS120/250
- Distribution / Core: Catalyst 9400 or 9600 (or 9500 in smaller campuses)
- Data center: Nexus 9300 (leaf/spine) + 9500/9800 (spine/super-spine)
7. Quick Selection Guide (2025)
| Need | Recommended Series |
|---|---|
| Small office, 8–24 ports, PoE | Catalyst 1000 or 1200 |
| Medium-large campus, advanced features | Catalyst 9300 / 9400 |
| Cloud-managed, zero-touch | Meraki MS |
| High-density 100G/400G data center | Nexus 9300-FX3/GX2/HX |
| Industrial / outdoor | IE-4000 / IE-9300 |
| SD-WAN edge | Catalyst 8300 / 8500 |
Cisco switches remain the de-facto standard in most enterprises because of their reliability, massive feature depth, long support cycles (often 10+ years), and the huge ecosystem of engineers trained on them.
If you have a specific use case (campus, data center, industrial, budget, port speed, etc.), I can give a much more targeted recommendation.