In contention resolution, multiple processors are trying to coordinate to send discrete messages through a shared channel with limited communication. If two processors send at the same time, the messages collide and are not transmitted successfully. Queue-free backoff protocols are an important special case - for example, Google Drive and AWS instruct their users to implement binary exponential backoff to handle busy periods. It is a long-standing conjecture of Aldous (IEEE Trans. Inf. Theory 1987) that no stable backoff protocols exist for any positive arrival rate of processors. This foundational question remains open; instability is only known in general when the arrival rate of processors is at least 0.42 (Goldberg et al. SICOMP 2004). We prove Aldous' conjecture for all backoff protocols outside of a tightly-constrained special case using a new domination technique to get around the main difficulty, which is the strong dependencies between messages.

翻译：在竞争解决中，多个处理器试图协调通过具有有限通信能力的共享信道发送离散消息。如果两个处理器同时发送，消息会发生冲突且无法成功传输。无队列退避协议是一个重要的特例——例如，Google Drive 和 AWS 指示其用户实施二进制指数退避以处理繁忙时段。Aldous（IEEE Trans. Inf. Theory 1987）长期以来的猜想是：对于处理器的任意正到达率，不存在稳定的退避协议。这一基础性问题至今悬而未决；目前仅知当处理器到达率至少为 0.42 时，协议普遍不稳定（Goldberg 等人，SICOMP 2004）。我们通过使用新的支配技术来克服消息间强依赖性的主要困难，证明了 Aldous 猜想对所有严格受限特例之外的退避协议均成立。