The active-fault-alarm （AFA） technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile （MPLS-TP） are both studied in this article. ...The active-fault-alarm （AFA） technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile （MPLS-TP） are both studied in this article. On this basis, an active dynamic pre-protection （ADPP） mechanism is proposed. This active dynamic pre-protection mechanism is allowed to establish a so called temporary protection path （TPP） for the work path before a potential fault occurs and to switch to TPP only after the fault occurs. It keeps the TPP flexibly only when it is in low- quality or fault state to realize dynamic protection even better and to achieve better resource utilization. Simulation results show that the proposed new mechanism has better performance in terms of the flexibility and the efficiency from the perspective of time.展开更多
By allowing routers to combine the received packets before forwarding them,network coding-based applications are susceptible to possible malicious pollution attacks.Existing solutions for counteracting this issue eith...By allowing routers to combine the received packets before forwarding them,network coding-based applications are susceptible to possible malicious pollution attacks.Existing solutions for counteracting this issue either incur inter-generation pollution attacks(among multiple generations)or suffer high computation/bandwidth overhead.Using a dynamic public key technique,we propose a novel homomorphic signature scheme for network coding for each generation authentication without updating the initial secret key used.As per this idea,the secret key is scrambled for each generation by using the generation identifier,and each packet can be fast signed using the scrambled secret key for the generation to which the packet belongs.The scheme not only can resist intra-generation pollution attacks effectively but also can efficiently prevent inter-generation pollution attacks.Further,the communication overhead of the scheme is small and independent of the size of the transmitting files.展开更多
We study thermal spin squeezing (TSS) and thermal global entanglement (TGE) in a general Heisenberg spin chain, in the presence of Dzyaloshinskii-Moriya interaction and an external magnetic field. We derive an inequal...We study thermal spin squeezing (TSS) and thermal global entanglement (TGE) in a general Heisenberg spin chain, in the presence of Dzyaloshinskii-Moriya interaction and an external magnetic field. We derive an inequality associating the squeezing parameter and the global concurrence, which establishes (TSS) as a signature of (TGE). The inequality reduces to equality for particular symmetric chains which also associates TSS with bipartite entanglement in such systems. We also check the results by presenting two numerical examples.展开更多
基金Supported by the National High Technology Research and Development Program of China（No. 2009AA01Z255, 2009AA01A345）, the National Basic Research Program of China（No. 2007CB310705 ） and the National Natural Science Foundation of China（No. 60932004）.
文摘The active-fault-alarm （AFA） technologies and the dynamic protection mechanism of the optical network controlled by the multi-protocol label switching transport profile （MPLS-TP） are both studied in this article. On this basis, an active dynamic pre-protection （ADPP） mechanism is proposed. This active dynamic pre-protection mechanism is allowed to establish a so called temporary protection path （TPP） for the work path before a potential fault occurs and to switch to TPP only after the fault occurs. It keeps the TPP flexibly only when it is in low- quality or fault state to realize dynamic protection even better and to achieve better resource utilization. Simulation results show that the proposed new mechanism has better performance in terms of the flexibility and the efficiency from the perspective of time.
基金supported by the National Natural Science Foundation of China under Grant No. 61271174
文摘By allowing routers to combine the received packets before forwarding them,network coding-based applications are susceptible to possible malicious pollution attacks.Existing solutions for counteracting this issue either incur inter-generation pollution attacks(among multiple generations)or suffer high computation/bandwidth overhead.Using a dynamic public key technique,we propose a novel homomorphic signature scheme for network coding for each generation authentication without updating the initial secret key used.As per this idea,the secret key is scrambled for each generation by using the generation identifier,and each packet can be fast signed using the scrambled secret key for the generation to which the packet belongs.The scheme not only can resist intra-generation pollution attacks effectively but also can efficiently prevent inter-generation pollution attacks.Further,the communication overhead of the scheme is small and independent of the size of the transmitting files.
文摘We study thermal spin squeezing (TSS) and thermal global entanglement (TGE) in a general Heisenberg spin chain, in the presence of Dzyaloshinskii-Moriya interaction and an external magnetic field. We derive an inequality associating the squeezing parameter and the global concurrence, which establishes (TSS) as a signature of (TGE). The inequality reduces to equality for particular symmetric chains which also associates TSS with bipartite entanglement in such systems. We also check the results by presenting two numerical examples.
