passive hub

基本解释

The device can also be used as a standalone four-channel passive UTP receiver hub with integral distributed camera power outputs rated at one amp each.
同時，模塊也可以作爲一個單獨的“四頻道的被動UTP接收器”，與各分佈的攝像頭電源輸出集成使用。
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The Terracotta "hub" prior to v2.3 was itself clusterable for fault-tolerance using an active/passive solution using shared disk (such as clustered NFS or SAN), which can be expensive.
在2.3版之前Terracotta的Hub使用共享硬磐（一個群集的NFS或者SAN）來實現活動/備用的群集故障容錯方案，這樣做的代價是高昂的。