OpenSFF Enclosure Specification

6. Network Infrastructure

Enclosure network requirements vary by enclosure type:

• Enterprise Enclosures MUST implement both a general-purpose internal Ethernet switch fabric and an out-of-band Management Network
• Core Enclosures MAY implement vendor-defined internal networking, but are not required to do so. Any such implementation MUST NOT be presented as Enterprise-compatible unless all Enterprise requirements are met

6.1 Internal Ethernet Switch Fabric

A shared, general-purpose Ethernet switch MUST interconnect all compute nodes. This fabric:

• Connects to the two Ethernet ports provided by each node’s Enterprise connector
• Exposes one or more uplinks on the enclosure for external access (e.g., RJ45, SFP+)

This network is intended for peer-to-peer communication, uplinked data flow, or application-specific clustering. It MUST remain logically and electrically distinct from the Management Network described in Section 6.2.

6.2 Management Network (Out-of-Band)

The Management Network is a dedicated control-plane fabric for diagnostics, enumeration, and firmware orchestration. It consists of:

• A reserved USB 3.0 port on each compute node
• A USB-to-Ethernet bridge on the enclosure backplane
• A private internal Ethernet switch, fully isolated from the main switch fabric

This network MUST NOT be used for general-purpose traffic. Its purposes are:

• Node identification and slot-based enumeration
• Synchronization or recovery of configuration data
• Upgrade rollback handling
• Storage of per-node JSON metadata

Access to this network is determined by the installed management module. The two standard MM types are summarized below: