Mobile Instant Messaging (IM) apps, such as WhatsApp and WeChat, frequently send heartbeat messages to remote servers to maintain their always-online status. Periodic heartbeat messages are small in size, but their transmissions incur heavy signaling traffic due to frequently establishing and releasing communication channels between Base Stations (BSs) and smartphones, known as the signaling storm. Meanwhile, smartphones also need to activate the cellular data communication module frequently for transmitting short heartbeat messages, resulting in substantial energy consumption. To address these issues, we present eDirect, an energy-efficient D2D-assIsted Relaying framEwork for Cellular signaling reducTion. eDirect selects active smartphones as relays to opportunistically collect heartbeat messages from nearby smartphones using energy-efficient D2D communication. The collected heartbeat messages are transmitted to the BS in an aggregated manner to reduce cellular signaling traffic. Based on the beating frequencies and deadlines of the collected heartbeat messages, eDirect schedules transmissions of the collected heartbeat messages to minimize signaling overhead and energy consumption while meeting the deadline constraints. We implement and evaluate our solution on Android smartphones. The results from real-world experiments show that our solution reduces signaling traffic by at least 50% and energy consumption by up to 36%.

中文翻译：

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eDirect：节能的D2D辅助中继框架，可减少蜂窝信号

WhatsApp和WeChat等移动即时消息（IM）应用程序经常将心跳消息发送到远程服务器，以保持其始终在线状态。周期性心跳消息的大小很小，但是由于频繁在基站（BS）和智能手机之间建立和释放通信通道，因此其传输会导致大量信令流量，这被称为信令风暴。同时，智能手机还需要频繁激活蜂窝数据通信模块以发送短的心跳消息，从而导致大量能源消耗。为了解决这些问题，我们提出了eDirect，一种节能的D2D辅助中继帧，用于减少蜂窝信令。eDirect选择活动的智能手机作为中继，以利用节能的D2D通信机会从附近的智能手机收集心跳消息。所收集的心跳消息以聚合的方式发送到BS以减少蜂窝信令业务。根据收集的心跳消息的跳动频率和截止时间，eDirect会调度收集的心跳消息的传输，以在满足截止时间限制的同时最大程度地降低信令开销和能耗。我们在Android智能手机上实施和评估我们的解决方案。实际实验的结果表明，我们的解决方案将信令流量减少了至少50％，能耗降低了36％。所收集的心跳消息以聚合的方式发送到BS以减少蜂窝信令业务。根据收集的心跳消息的跳动频率和截止时间，eDirect会调度收集的心跳消息的传输，以在满足截止时间限制的同时最大程度地降低信令开销和能耗。我们在Android智能手机上实施和评估我们的解决方案。实际实验的结果表明，我们的解决方案将信令流量减少了至少50％，能耗降低了36％。所收集的心跳消息以聚合的方式发送到BS以减少蜂窝信令业务。根据收集的心跳消息的跳动频率和截止时间，eDirect会调度收集的心跳消息的传输，以在满足截止时间限制的同时最大程度地降低信令开销和能耗。我们在Android智能手机上实施和评估我们的解决方案。实际实验的结果表明，我们的解决方案将信令流量减少了至少50％，能耗降低了36％。我们在Android智能手机上实施和评估我们的解决方案。实际实验的结果表明，我们的解决方案将信令流量减少了至少50％，能耗降低了36％。我们在Android智能手机上实施和评估我们的解决方案。实际实验的结果表明，我们的解决方案将信令流量减少了至少50％，能耗降低了36％。