If you are in routing and switching industry, it’s almost impossible not to hear words like MSFC, PFC and DFC in relation with Cisco Catalyst 6500 series, chassis, supervisor and modules. If you didn’t yet, you’re not almost there, working with large enterprise environments.
Even if I see an increasing use of Nexus switches, C65k are and will still play an important role in next few years. I know that there will be voices out there standing that 6500 series is almost EoL. Nevertheless, this rumors where there also 4-5 years ago. My point is that you should know something about this platform and MSFC, PFC and DFC are playing an important role.
Anyway what are this acronyms?
MSFC (Multilayer Switch Feature Card)
Multilayer Switch Feature Card is the Layer 3 switching engine that sites on the Catalyst Supervisor as a daughter card. The MSFC is an integral part of the Supervisor Engine, providing high performance, multilayer switching and routing intelligence
PFC (Policy Feature Card)
The PFC provides the necessary ASICs to perform hardware-based Layer 3 switching, quality of service (QoS) classification, and access control list (ACL) filtering.
DFC (Distributed Feature Card)
The Distributed Feature Card (DFC) allows fabric-enabled line cards to make L3 forwarding decisions locally without requiring the L3 switching engine located on the Supervisor PFC. The DFC consists of the same components as the PFC located on the Supervisor module, however it does not contain the MSFC routing engine
This is the basic explanation for those three words, but it does not say to much, isn’t it? For more details please see the article of Sunil Khanna on Understanding MSFC, PFC and DFC roles in Catalyst 6500 Series Switch. It’s very short, comprehensive and give you a very good starting point to understand what each component does inside a C6500 series.