Introduction

The HIXL (unilateral communication library) provides C++ and Python APIs that deliver simple, reliable, and efficient point-to-point data transmission capabilities for cluster scenarios.

**Table 1** Use cases
Manual	Description
HIXL API Reference (C++)	Describes HIXL APIs for C++, including link management, memory management, and data transmission. In distributed memory pool scenarios, HIXL provides a pure transmission capability based on local and remote addresses. D2D, D2H, and H2D transmission are supported in this scenario. Describes LLM-DataDist APIs for C++, including link management and KV cache management. This scenario supports one-way link establishment. Decode and Prompt can bidirectionally pull and push the KV cache.
HIXL API Reference (Python)	Describes LLM-DataDist APIs for Python, including link management and KV cache management in CacheManager mode. This scenario supports one-way and two-way link establishment. That is, all LLM-DataDist instances involved in communication initiate link establishment simultaneously (for two-way mode). Decode and Prompt can bidirectionally pull and push the KV cache. D2D, D2H, and H2D transmission are supported in this scenario.