What are the common VLAN pruning and filtering scenarios and use cases in your industry?

1 VLAN pruning basics

VLAN pruning is the process of removing VLANs from a trunk link that are not needed by the devices on either end. This reduces the bandwidth consumption, the CPU load, and the potential for broadcast storms on the trunk link. VLAN pruning can be done manually by configuring the allowed VLAN list on each trunk port, or automatically by using protocols such as VTP or DTP. VLAN pruning is especially useful when you have a large number of VLANs in your network, but only a few of them need to communicate across different switches.

2 VLAN filtering basics

VLAN filtering is the process of restricting the access and communication between different VLANs based on certain criteria, such as IP addresses, MAC addresses, or protocols. VLAN filtering can be done at the layer 2 level by using VLAN access control lists (VACLs), or at the layer 3 level by using inter-VLAN routing and access control lists (ACLs). VLAN filtering can enhance the security and isolation of your network, as well as prevent unauthorized or unwanted traffic from reaching certain VLANs.

3 VLAN pruning and filtering for data centers

One of the common scenarios where VLAN pruning and filtering are used is in data centers, where you have a high-density and high-performance network that supports various applications and services. VLAN pruning can help you reduce the overhead and complexity of managing hundreds or thousands of VLANs across multiple switches, as well as improve the availability and reliability of your network. VLAN filtering can help you segment your network into different zones, such as production, development, testing, and management, and enforce the appropriate policies and rules for each zone. This can improve the security and compliance of your data center, as well as the efficiency and performance of your applications and services.

4 VLAN pruning and filtering for campus networks

Another common scenario where VLAN pruning and filtering are used is in campus networks, where you have a large and diverse network that supports various users and devices. VLAN pruning can help you optimize the use of your trunk links, as well as simplify the troubleshooting and maintenance of your network. VLAN filtering can help you create different VLANs for different groups of users and devices, such as students, faculty, staff, guests, wireless, VoIP, and video. This can enhance the security and privacy of your network, as well as the quality of service and user experience for each group.

5 VLAN pruning and filtering for service providers

A third common scenario where VLAN pruning and filtering are used is in service provider networks, where you have a scalable and flexible network that delivers various services and solutions to your customers. VLAN pruning can help you conserve the resources and capacity of your network, as well as reduce the risk of errors and misconfigurations. VLAN filtering can help you isolate and protect your customers' traffic and data, as well as provide them with customized and differentiated services and solutions. This can increase the profitability and competitiveness of your service provider business, as well as the satisfaction and loyalty of your customers.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?