The following tables detail the algorithms supported by different product models for inter-server communication, as well as the communication operators compatible with each algorithm. Any item not listed in the tables indicates lack of support.

Atlas 350 Accelerator Card

NHR algorithm

Collective Communication Operator	Data Type	Network Running Mode	Operator Expansion Mode
ReduceScatter	int8, int16, int32, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	AI_CPU/CCU_SCHED
AllGather	int8, int16, int32, int64, uint8, uint16, uint32, uint64, float16, float32, float64, bfp16, fp8-e5m2, fp8-e4m3, hif8, and fp8-e8m0	Single-operator mode Graph mode (Ascend IR)	AI_CPU/CCU_SCHED
AllReduce	int8, int16, int32, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	AI_CPU/CCU_SCHED
Broadcast	int8, int16, int32, int64, uint8, uint16, uint32, uint64, float16, float32, float64, bf16, fp8-e5m2, fp8-e4m3, hif8, and fp8-e8m0	Single-operator mode Graph mode (Ascend IR)	AI_CPU/CCU_SCHED
Reduce	int8, int16, int32, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	AI_CPU/CCU_SCHED
Scatter	int8, int16, int32, int64, uint8, uint16, uint32, uint64, float16, float32, float64, bf16, fp8-e5m2, fp8-e4m3, hif8, and fp8-e8m0	Single-operator mode	AI_CPU/CCU_SCHED
Broadcast	int8, int16, int32, int64, uint8, uint16, uint32, uint64, float16, float32, float64, bf16, fp8-e5m2, fp8-e4m3, hif8, and fp8-e8m0	Single-operator mode Graph mode (Ascend IR)	AI_CPU/CCU_SCHED

Atlas A3 training product/Atlas A3 inference product

Ring algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
Reduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
ReduceScatterV	int8, int16, int32, int64 (supported only in single-operator mode), float16, float32, and bfp16	Single-operator mode	The NHR or H-D_R algorithm is automatically selected.
Scatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The NHR or H-D_R algorithm is automatically selected.
AllGatherV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The NHR or H-D_R algorithm is automatically selected.

NHR algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
ReduceScatterV	int8, int16, int32, int64 (supported only in single-operator mode), float16, float32, and bfp16	Single-operator mode	The H-D_R or ring algorithm is automatically selected.
Scatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The H-D_R or ring algorithm is automatically selected.
AllGatherV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The H-D_R or ring algorithm is automatically selected.

NB algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
ReduceScatterV	int8, int16, int32, int64 (supported only in single-operator mode), float16, float32, and bfp16	Single-operator mode	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGatherV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The NHR, H-D_R, or ring algorithm is automatically selected.
Scatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The NHR, H-D_R, or ring algorithm is automatically selected.

AHC algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.

Atlas A2 training product/Atlas A2 inference product

Ring algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
Reduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
ReduceScatterV	int8, int16, int32, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
Scatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The NHR or H-D_R algorithm is automatically selected.
AllGatherV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.

H-D_R algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.
Reduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.

NHR algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
ReduceScatterV	int8, int16, int32, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
Scatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The H-D_R or ring algorithm is automatically selected.
AllGatherV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.

NHR_V1 algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.

NB algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
ReduceScatterV	int8, int16, int32, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGatherV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
Scatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The NHR, H-D_R, or ring algorithm is automatically selected.

Pipeline algorithm

Note: For the Atlas A2 training product/Atlas A2 inference product, deterministic computation cannot be enabled when the pipeline algorithm is selected; otherwise, the pipeline algorithm will not take effect.

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
AllReduce	int8, int16, int32, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR): For floating-point compute overflow modes, the saturation mode is not supported; only INF and NaN modes are supported.	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGatherV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
ReduceScatter	int8, int16, int32, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AlltoAll	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Dynamic shape scenario of the graph mode (Ascend IR)	The pairwise algorithm is automatically selected.
AlltoAllV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Dynamic shape scenario of the graph mode (Ascend IR)	The pairwise algorithm is automatically selected.
AlltoAllVC	int8, int16, int32, int64, float16, float32, and bfp16	Dynamic shape scenario of the graph mode (Ascend IR)	The pairwise algorithm is automatically selected.

Pairwise algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
AlltoAll	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AlltoAllV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AlltoAllVC	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.

CP algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
AlltoAllV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The pairwise algorithm is automatically selected.

Atlas training product

Ring algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.
Reduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or H-D_R algorithm is automatically selected.

H-D_R algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.
Reduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR or ring algorithm is automatically selected.

NHR algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The H-D_R or ring algorithm is automatically selected.

NHR_V1 algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.

NB algorithm

Collective Communication Operator	Data Type	Network Running Mode	Handling Method for Unsupported Operators
ReduceScatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGather	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
AllReduce	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
Broadcast	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode Graph mode (Ascend IR)	The NHR, H-D_R, or ring algorithm is automatically selected.
ReduceScatterV	int8, int16, int32, float16, float32, and bfp16	Single-operator mode	The NHR, H-D_R, or ring algorithm is automatically selected.
AllGatherV	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The NHR, H-D_R, or ring algorithm is automatically selected.
Scatter	int8, int16, int32, int64, float16, float32, and bfp16	Single-operator mode	The NHR, H-D_R, or ring algorithm is automatically selected.

List of Supported Algorithms for Inter-Server Communication

Atlas 350 Accelerator Card

Atlas A3 training product/Atlas A3 inference product

Atlas A2 training product/Atlas A2 inference product

Atlas training product