摘要 |
In a system of local DHT overlays, each has KVS nodes, including one super node. The super nodes organize a global DHT overlay. Each super node maintains Bloom filters of keys in its local DHT overlay for all key ranges. To obtain data corresponding to a key from other local DHT overlays, a super node sends a request to a node which is responsible for the key range hashed from the specified key. The responsible node determines local DHT overlays which may have data corresponding to the key according to Bloom filters registered in the super nodes of the local DHT overlays, updated and converted from counting filters. Requests are sent to the super nodes of the local DHT overlays identified by the responsible node. Thus, requests are not needlessly sent to super nodes of local DHT overlays which do not have data corresponding to the key, thereby reducing traffic. |