If you manage an enterprise network infrastructure, implementing effective network segmentation should be one of your top priorities. But with the overlap between technologies like VLANs and VXLAN, it can be confusing to know which approach is best.
In this comprehensive guide, I’ll arm you with in-depth knowledge of how VLANs and VXLAN enable network segmentation. Well explore the key capabilities of each, along with deployment considerations. By the end, you’ll have the insight needed to make smart decisions for your infrastructure. Let’s get started!
Why Network Segmentation Matters
Before diving into the two technologies, it’s important to level-set on what network segmentation entails and why it should be a priority.
Network segmentation involves splitting networks into smaller segments or subnetworks. This contains traffic flows and protects sensitive resources. Rather than the traditional “flat” network, you create dedicated network segments based on departments, applications, data sensitivity levels, and more.
This approach unlocks a wealth of benefits:
Security
- Reduce attack surface by hiding applications and servers
- Control lateral movement to limit breach impact
- Deploy defenses and policies by segment
Performance
- Reduce congestion with contained broadcasts
- Apply quality of service controls more granularly
- Scale bandwidth as needed per segment
Compliance
- Isolate sensitive systems to satisfy regulations
- Clearly define network control boundaries
- Tighten access controls and auditing
Agility
- Onboard new acquisitions more easily
- Test changes in lower environments
- Extend consistent policies everywhere
Leading analysts recommend aiming for 75% network segmentation coverage within 12 months to maximize these benefits.
The two most viable technologies for enabling dynamic network segmentation are VLANs and VXLAN. Let’s explore how each one works.
VLANs: Established and Reliable Segmentation
VLANs (Virtual Local Area Networks) are one of the most popular network segmentation mechanisms leveraged in enterprises today. First defined officially in the 802.1Q standard, VLANs logically divide physical network infrastructure.
How VLANs Segment Networks
The magic of VLANs happens using tags and trunks:
- Tags – A VLAN tag or ID between 1-4094 is assigned to each frame. This determines the VLAN membership of a frame.
- Trunks – VLAN-tagged frames are carried between network switches over VLAN trunk links. This allows devices in different VLANs to communicate.
Grouping devices into separate VLANs isolates broadcast traffic, enforces security policies, and simplifies management.
Here’s a high-level view of VLAN segmentation:
VLANs can extend across the entire LAN, connecting devices across access closets and floors. This provides extensive coverage using your existing network hardware.
Key Capabilities of VLANs
Some of the core capabilities enabled by VLAN technology include:
Flexible configuration – VLAN membership can be set according to port, MAC address, protocol, or other parameters. This supports a range of static and dynamic grouping policies.
Native security – Traffic isolation, unauthorized access prevention, and broadcast containment help enforce perimeter defenses within the LAN environment.
Traffic management – Prioritization and QoS controls can be implemented per VLAN to meet application performance SLAs.
Simplified administration – Devices and policies are managed according to VLAN grouping rather than physical ports or hierarchy. This accelerates change management.
For these reasons, VLANs became the go-to for most network segmentation initiatives. But this prevalent technology does come with some limitations…
Where VLAN Segmentation Falls Short
VLAN deployment reaches certain barriers, especially for large and complex environments:
- Limited scale – With only 4094 possible VLAN IDs, segmentation density is constrained. Exceeding this can get very complex.
- Spanning sites – Native VLANs operate at layer 2 so extending segmentation across sites is challenging.
- Virtualization support – Integrating VLANs with software-defined and virtualized infrastructure adds complexity.
Modern data centers and multi-site networks can stretch VLAN technology past its limits. This sparked the emergence of new overlay approaches like VXLAN.
VXLAN: Next-Generation Network Virtualization
Seeking to expand on VLAN capabilities for virtualized and cloud-centric environments, VXLAN (Virtual eXtensible LAN) emerged as an overlay network alternative. First proposed in 2009, VXLAN addresses many of the limitations of traditional VLAN segmentation.
How VXLAN Enables Segmentation
Rather than using VLAN IDs to logical divide layer 2 networks, VXLAN leverages encapsulation and tunneling techniques:
- Traffic is encapsulated with a VXLAN header containing source/destination endpoint IDs and a segment ID.
- Packets are transported over overlay tunnels via the physical IP network between VXLAN endpoints.
This enables the creation of isolated layer 2 virtual networks mapped over the underlying network architecture.
Here’s a simplified illustration of the VXLAN approach:
The underlying IP network switches simply move the encapsulated VXLAN packets between the endpoints. The endpoints handle encapsulation, tunneling, and mapping of virtual to physical resources.
Benefits of VXLAN Segmentation
This virtualized approach unlocks capabilities far beyond what VLANs can offer, including:
Limitless scale – Support for over 16 million VXLAN segments compared to VLAN’s 4096 limit.
Flexible topology – Virtual networks can span across IP networks and physical sites or cloud regions. Resources are fully decoupled.
Cloud optimized – Integrates seamlessly with virtualization platforms and software-defined overlay management.
As data center architecture shifted to software-defined on commodity hardware, VXLAN emerged as the ideal network virtualization foundation.
Adoption exploded from as early as 2012 across public cloud platforms like AWS and Azure. VXLAN penetration continues to grow steadily according to research:
When to Choose VXLAN
With its advanced capabilities beyond VLAN limitations, VXLAN is the segmentation mechanism of choice for:
- Multi-site data centers – Extend architecture consistently across regions or branches
- Cloud-native environments – Integrate infrastructure seamlessly with cloud virtualization
- Software-defined networks – Programmatically manage overlay abstractions
- High scale segmentation – Expand to tens of thousands of isolated networks
- Container networking – Connect groups of containers across hosts
Leading data center and network vendors like Cisco, HPE, Dell, Juniper all support VXLAN either natively or via gateway appliances. This facilitates deployment across your infrastructure.
Comparing VLAN and VXLAN Capabilities
Now that you understand the basics of how VLANs and VXLAN enable network segmentation, let’s compare some of their key capabilities and limitations side by side:
| VLAN | VXLAN | |
|---|---|---|
| Native Technology | Yes | Overlay extension |
| Topology | LAN segmentation | Flexible overlay |
| Transport | Layer 2 (Ethernet) | Encapsulated L2 over L3/IP |
| Scalability | 4K segments | 16M+ segments |
| Multi-site | Limited (L2) | Yes, over L3 core |
| Cloud Support | Challenging | Purpose-built |
| Orchestration | Manual | Automated |
As an early network virtualization innovation, VXLAN helps break through the scale, flexibility, and integration limitations of VLAN technology. This enables next-generation network architectures.
Deployment Considerations
Adopting any network segmentation technology comes with a set of planning, upgrade, and management considerations:
Assessment – Analyze infrastructure readiness, identify resource groups, model policies
Hardware – Ensure switches support features like VXLAN encapsulation and multi-tenancy
Tooling – Upgrade management platforms to improve monitoring, automation and analytics with new abstractions
Transition – Gradually update network architecture without disruption as infrastructure lifecycles allow
For both VLAN and VXLAN environments, maintaining high availability, business continuity, and security are key during and after deployment.
Final Recommendations
Hopefully this overview clarifies the purpose and capabilities of VLANs vs. VXLAN for strategically segmenting your networks.
As networks evolve to incorporate next-generation infrastructure, VXLAN paves the way for flexible, cloud-centric designs. For maximizing scale, utilization, and automation, VXLAN is ideal for most modernization efforts.
That said, many networks still rely heavily on existing VLAN deployment that works smoothly today. A hybrid approach that extends VLAN environments via VXLAN gateways enables a graceful transition over time.
I encourage developing a phased deployment plan that maps technologies to network evolution priorities. This lets you tackle quick-win use cases first, while building towards long-term transformation vision.
Feel free to reach out if you have any other questions! I‘m always happy to discuss best practices to enhance your network architecture, security, and readiness for the future.
