Featured with high bandwidth, high reliability, and native IP compatibility, WiFi has been recommended for a wide range of Internet-of-Things (IoT) applications. However, WiFi is inherently energy-hungry and it may impose high energy consumption on not only IoT devices but also gateways. To reduce gateway's WiFi energy consumption, many energy-efficient solutions for WiFi tethering services can be applied. However, these solutions mainly target the energy optimization of downlink data traffic in WLANs, and they are not suitable for the uplink data traffic of delivering massive IoT data from device to gateway (D2G), which is more common in IoT. When a gateway is powered by batteries, the high energy consumption caused by D2G communications may deplete the gateway quickly and renders the whole system dysfunctional as a result. Toward achieving energy-efficient D2G communications, we propose an innovative Green IoT Gateway (GIG) scheme, which aims at minimizing gateway energy consumption while ensuring the specific delay requirements of devices via cross-interface collaboration. Through utilizing the coexisting low-power ZigBee radios, GIG dynamically schedules the wakeup behaviors of high-power WiFi radios for energy-efficient and delay-bounded D2G communications. GIG has been implemented and evaluated in a prototype system, and the experiment results show that, under the moderate uplink data traffic and delay requirements, the energy consumption of GIG is 38.5% and 12.7% lower than those of a state-of-the-art WiFi tethering scheme and a simple version of the GIG scheme, respectively. Moreover, a great reduction of energy consumption at the device side can also be observed.

中文翻译：

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物联网中实现节能设备到网关通信的跨接口调度


WiFi 具有高带宽、高可靠性和原生 IP 兼容性等特点，已被推荐用于各种物联网 (IoT) 应用。然而，WiFi本质上是高耗能的，它不仅会给物联网设备带来高能耗，也会给网关造成高能耗。为了降低网关的 WiFi 能耗，可以应用许多用于 WiFi 网络共享服务的节能解决方案。然而，这些解决方案主要针对WLAN中下行数据流量的能量优化，并不适合物联网中更常见的从设备到网关（D2G）传送海量物联网数据的上行数据流量。当网关采用电池供电时，D2G通信带来的高能耗可能会迅速耗尽网关的电量，导致整个系统无法正常工作。为了实现节能的D2G通信，我们提出了一种创新的绿色物联网网关（GIG）方案，旨在最大限度地减少网关能耗，同时通过跨接口协作确保设备的特定延迟要求。通过利用共存的低功耗 ZigBee 无线电，GIG 动态调度高功率 WiFi 无线电的唤醒行为，以实现节能且有延迟限制的 D2G 通信。 GIG已经在原型系统中实现和评估，实验结果表明，在适度的上行数据流量和时延要求下，GIG的能耗比现有技术低38.5%和12.7%。分别是 art WiFi 网络共享方案和简单版本的 GIG 方案。此外，设备侧的能耗也大幅降低。