MAC-based VLANs vs 802.1p tagging (CoS)

Both MAC-based VLANs and 802.1p priority tagging can be part of a comprehensive QoS strategy, but they serve different roles and neither directly reduces latency or jitter. However, they can both contribute to a network environment that prioritizes certain traffic, which can help reduce latency and jitter for that traffic. Here's how:

• MAC-based VLANs: These segregate traffic based on the MAC address of the sender. By itself, this doesn't reduce latency or jitter. However, it can contribute to a more organized network structure, which can help manage traffic loads and potentially indirectly improve overall network performance.
• 802.1p tagging (CoS): This specifically tags Ethernet frames with a priority level. When network devices like switches and routers see these tags, they can prioritize traffic accordingly. In a congested network, this can help reduce latency and jitter for high-priority traffic by ensuring that high-priority packets are sent first.

Neither of these techniques will inherently provide lower latency or jitter as they are not designed to do so directly. Instead, they are tools that can be used as part of a broader QoS strategy.

For the lowest latency and jitter, you would generally need to ensure there's sufficient bandwidth for your needs, prioritize traffic correctly (where 802.1p can help), and minimize congestion as much as possible. Other tools and techniques, such as traffic shaping and proper network design, will also be important. The exact best practices can vary depending on the specific requirements of your network and the type of traffic you're dealing with.