Discovery of service nodes in flows is a challenging task, especially in large ISPs or campus networks where the amount of traffic across net-work is rmssive. We propose an effective data structure called Round-robin ...Discovery of service nodes in flows is a challenging task, especially in large ISPs or campus networks where the amount of traffic across net-work is rmssive. We propose an effective data structure called Round-robin Buddy Bloom Filters （RBBF） to detect duplicate elements in flows. A two-stage approximate algorithm based on RBBF which can be used for detecting service nodes from NetFlow data is also given and the perfonmnce of the algorithm is analyzed. In our case, the proposed algorithm uses about 1% memory of hash table with false positive error rate less than 5%. A proto-type system, which is compatible with both IPv4 and IPv6, using the proposed data structure and al-gorithm is introduced. Some real world case studies based on the prototype system are discussed.展开更多
As oil and gas development gets more difficult, the market competition in engineering technology services tends to be fiercer. CNPC mud logging business is facing double challenges from tedmology and market. We analyz...As oil and gas development gets more difficult, the market competition in engineering technology services tends to be fiercer. CNPC mud logging business is facing double challenges from tedmology and market. We analyzed both external and internal environment for CNPC logging business development, made clear the opportunities and challenges, gained insights in to the existing problems, and proposed countermeasu res from the aspects of management system, service mode, proyqtability, techniques and equipment, market expansion, and personnel training.展开更多
基金supported by the National Basic Research Program of China under Grant No. 2009CB320505
文摘Discovery of service nodes in flows is a challenging task, especially in large ISPs or campus networks where the amount of traffic across net-work is rmssive. We propose an effective data structure called Round-robin Buddy Bloom Filters （RBBF） to detect duplicate elements in flows. A two-stage approximate algorithm based on RBBF which can be used for detecting service nodes from NetFlow data is also given and the perfonmnce of the algorithm is analyzed. In our case, the proposed algorithm uses about 1% memory of hash table with false positive error rate less than 5%. A proto-type system, which is compatible with both IPv4 and IPv6, using the proposed data structure and al-gorithm is introduced. Some real world case studies based on the prototype system are discussed.
文摘As oil and gas development gets more difficult, the market competition in engineering technology services tends to be fiercer. CNPC mud logging business is facing double challenges from tedmology and market. We analyzed both external and internal environment for CNPC logging business development, made clear the opportunities and challenges, gained insights in to the existing problems, and proposed countermeasu res from the aspects of management system, service mode, proyqtability, techniques and equipment, market expansion, and personnel training.
