论文标题
流式码的流式代码中的在线与离线率
Online Versus Offline Rate in Streaming Codes for Variable-Size Messages
论文作者
论文摘要
在提供高质量的现场沟通服务方面，一个普遍的挑战是实时恢复丢失的数据包。流码是一类擦除代码，这些代码是为如此严格，低延迟流的通信设置而设计的。本文以传输消息随时间变化（例如实时视频流）变化的应用程序的激励，本文考虑了在可变尺寸消息下的流码设置。实际上，流码在“在线”设置中运行，其中未来消息的大小未知。相比之下，“离线”代码可以访问所有消息的大小，包括将来的消息。本文介绍了第一个在线速率 - 最佳流媒体代码，用于通过仅爆发的数据包丢失通道进行两个广泛参数制度进行通信。尽管离线设置显然具有优势，但这两个在线代码与两种设置的最佳离线代码速率相匹配。本文进一步确定，在线代码无法达到所有剩余参数设置的离线代码的最佳率。
One pervasive challenge in providing a high quality-of-service for live communication is to recover lost packets in real-time. Streaming codes are a class of erasure codes that are designed for such strict, low-latency streaming communication settings. Motivated by applications that transmit messages whose sizes vary over time, such as live video streaming, this paper considers the setting of streaming codes under variable-size messages. In practice, streaming codes operate in an "online" setting where the sizes of the future messages are unknown. "Offline" codes, in contrast, have access to the sizes of all messages, including future ones. This paper introduces the first online rate-optimal streaming codes for communicating over a burst-only packet loss channel for two broad parameter regimes. These two online codes match the rates of optimal offline codes for the two settings despite the apparent advantage of the offline setting. This paper further establishes that online codes cannot attain the optimal rate for offline codes for all remaining parameter settings.
