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Confidential Computing instance profiles - x86 Gen 3

Confidential Computing instance profiles - x86 Gen 3

The confidential computing family of 3rd generation IBM Cloud® VPC virtual server profiles (balanced and compute) are built atop the 4th Generation Intel® Xeon® Scalable processors. The confidential computing profiles provide a broad set of capabilities and scale from 2 vCPUs (1 physical core) up to 128 vCPUs (64 physical cores). These profiles support the Intel SGX confidential computing capability.

Operating systems

  • Linux

Processor generation

  • Intel 8474C - 4th Generation Xeon Scalable processor

Availability

  • SGX status: Select availability

  • Regions:

    • Dallas (us-south)
    • Washington DC (us-east)
    • Frankfurt (eu-de)

  • TDX Status: Select availability

  • Regions:

    • Washington DC (us-east)

Capabilities

  • Core type: Dedicated
  • Dedicated host: No
  • Hyperthreading: Yes (SMT-2)
  • Secure boot: Yes
  • Confidential computing: SGX, TDX
  • Live migration: No
  • Instance storage: Yes
  • Volume bandwidth allocation method: weighted by default, it can be updated to pooled.

VM configuration

  • Hardware type: q35
  • Cloud networking: virtio
  • Block boot volume: virtio
  • Block data volumes: virtio
  • Instance storage: virtio

Instance profiles

Balanced

Confidential computing balanced instance profile options for x86 architecture, Gen 3
Profile vCPUs / Cores / NUMA domains Memory (GiB) SGX mode TDX mode Bandwidth cap (Gbps) Instance storage (Qty x GB)
bx3dc-2x10 2 / 1 / 1 10 4 GB EPC 0 GB EPC 4 1 x 65
bx3dc-4x20 4 / 2 / 1 20 8 GB EPC 0 GB EPC 8 1 x 130
bx3dc-8x40 8 / 4 / 1 40 16 GB EPC 0 GB EPC 16 1 x 260
bx3dc-16x80 16 / 8 / 1 80 32 GB EPC 0 GB EPC 32 1 x 520
bx3dc-24x120 24 / 12 / 1 120 48 GB EPC 0 GB EPC 48 1 x 780
bx3dc-32x160 32 / 16 / 2 160 64 GB EPC 0 GB EPC 64 2 x 520
bx3dc-48x240 48 / 24 / 2 240 96 GB EPC 0 GB EPC 96 2 x 780
bx3dc-64x320 64 / 32 / 2 320 128 GB EPC 0 GB EPC 128 2 x 1024
bx3dc-96x480 96 / 48 / 2 480 192 GB EPC 0 GB EPC 192 2 x 1560

Compute

Confidential computing compute instance profile options for x86 architecture, Gen 3
Profile vCPUs / Cores / NUMA domains Memory (GiB) SGX mode TDX mode Bandwidth cap (Gbps) Instance storage (Qty x GB)
cx3dc-2x5 2 / 1 / 1 5 2 GB EPC 0 GB EPC 4 1 x 65
cx3dc-4x10 4 / 2 / 1 10 4 GB EPC 0 GB EPC 8 1 x 130
cx3dc-8x20 8 / 4 / 1 20 8 GB EPC 0 GB EPC 16 1 x 260
cx3dc-16x40 16 / 8 / 1 40 16 GB EPC 0 GB EPC 32 1 x 520
cx3dc-24x60 24 / 12 / 1 60 24 GB EPC 0 GB EPC 48 1 x 780
cx3dc-32x80 32 / 16 / 2 80 32 GB EPC 0 GB EPC 64 2 x 520
cx3dc-48x120 48 / 24 / 2 120 48 GB EPC 0 GB EPC 96 2 x 780
cx3dc-64x160 64 / 32 / 2 160 64 GB EPC 0 GB EPC 128 2 x 1024
cx3dc-96x240 96 / 48 / 2 240 96 GB EPC 0 GB EPC 192 2 x 1560
cx3dc-128x320 128 / 64 / 2 320 128 GB EPC 0 GB EPC 200 2 x 2860
  • These profiles configure EPC memory when used in SGX mode only. In TDX mode the EPC memory is not configured.
  • Any profile with more than 120 GB memory does not support TDX mode.

Limits

An instance has a limit for the number of volumes and virtual network interfaces that can be attached. This limit is based on the size of the instance.

Confidential computing profile family limits for vCPU, maximum volumes, and maximum network interfaces
Number of vCPUs Max volumes Max vNICs
2-16 12 5
17-48 12 10
49+ 12 15

Boot volume profiles

In the current release of Block Storage for VPC offering, only first-generation volumes from the tiered and custom volume profile families can be used as boot volumes for the Confidential Computing instances if secure boot is needed. Second-generation boot volumes with the sdp profile do not support secure boot.

SGX limitations

  • Windows guest not supported

TDX limitations

  • Windows guest not supported

    Windows guest operating systems do not support TDX natively.

  • VNC not supported

    The data that flows to the VNC console from the TDX virtual server is facilitated by the cloud provider. However, the cloud provider is not a trusted entity from the customer point of view. Since the data is exposed to the cloud provider, the TDX virtual server disables VNC.

  • Forced reboot leads to virtual server shutdown

    For security reasons TDX virtual servers cannot be reset without terminating the virtual server. A forced reboot that is invoked from the control plane resets the virtual server, effectively terminating it. However, this behavior can be masked by the control plane by automatically starting the virtual server. The control plane is enhanced to run the automatic restart.