Abstract: The present disclosure relates to an optical ranging device. The optical ranging device comprises a housing, a bottom cover, an emitting lens, a receiving lens and a circuit board. The emitting lens and the receiving lens are fixed on the circuit board. The circuit board comprises a light emitting module, receiving module and data processing and controlling module. An infrared light emitted by a light source of the light emitting module passes through the emitting lens and the housing successively and enters the external environment. The infrared light reflected by the object passes through the housing and the receiving lens successively and is received by the receiving module which is connected to a signal processing and controlling module. The distance between the optical ranging device and the object is calculated based on the Time of Flight principle.

Abstract: A data transmission acceleration method and related apparatuses are disclosed. A sanding node transmits a plurality of data packets to a receiving node at an initial transmission rate. Each data packet carries a random sequence number and a rolling sequence number. The random sequence number identifies a data part of the data packet, and the rolling sequence number indicates a transmission sequence of the data packet. The sending node receives a packet loss feedback from the receiving node. The packet loss feedback is generated after the receiving node detects a packet loss event according to a rolling sequence number of a received data packet. The sending node determines a random sequence number of a lost data packet based on the received packet loss feedback. The sending node retransmits a data packet corresponding to the determined random sequence number. The retransmitted data packet carries a new rolling sequence number.

Abstract: The present invention discloses a method and apparatus for processing a data packet in a software defined network SDN protocol-based network. The method comprises: receiving a data packet forwarded by a SDN switch in the network; obtaining a rule corresponding to a data flow where the data packet is located; determining, according to the received data packet, data flow characteristics of the data flow where the data packet is located; determining timeout information of the rule according to a predetermined matching relationship between the data flow characteristics and the timeout information, the timeout information indicating time that the rule will be kept in a flow table of the SDN switch; and sending the rule and the timeout information of the rule to the SDN switch for processing the data packet by the SDN switch according to the rule.

Abstract: The present invention discloses a method and apparatus for processing a data packet in a software defined network SDN protocol-based network. The method comprises: receiving a data packet forwarded by a SDN switch in the network; obtaining a rule corresponding to a data flow where the data packet is located; determining, according to the received data packet, data flow characteristics of the data flow where the data packet is located; determining timeout information of the rule according to a predetermined matching relationship between the data flow characteristics and the timeout information, the timeout information indicating time that the rule will be kept in a flow table of the SDN switch; and sending the rule and the timeout information of the rule to the SDN switch for processing the data packet by the SDN switch according to the rule.

Abstract: The present invention discloses a method and apparatus for processing a data packet in a software defined network SDN protocol-based network. The method comprises: receiving a data packet forwarded by a SDN switch in the network; obtaining a rule corresponding to a data flow where the data packet is located; determining, according to the received data packet, data flow characteristics of the data flow where the data packet is located; determining timeout information of the rule according to a predetermined matching relationship between the data flow characteristics and the timeout information, the timeout information indicating time that the rule will be kept in a flow table of the SDN switch; and sending the rule and the timeout information of the rule to the SDN switch for processing the data packet by the SDN switch according to the rule.

Abstract: A fast scan detection method is provided. The fast scan detection method is applied to a rotatable scan detection device where two or more detection samplings are performed for calculating each scan detection distance value, where each of the detection samplings includes: emitting, by an emission light source, infrared detection light, where the infrared detection light propagates through a surrounding space and is reflected by a detected object when the infrared detection light encounters the detected object; and receiving, by a photoelectric sensor in a reception unit, the infrared detection light reflected by the detected object, where the rotatable scan detection device performs one detection sampling at each detection angular position at which the rotatable scan detection device is positioned.

Abstract: The present invention provides a recombinant strain, construction method thereof and a method for producing acid phosphatase using the recombinant strain. In the invention, the phosphatase gene is obtained from Pseudomonas aeruginosa by a molecular biology method, the constructed expression plasmid is transformed into E. coli BL21 (DE3). The purified enzyme and whole cells were used for the conversion of ascorbic acid to ascorbic acid-2-phosphate. Ascorbic acid-2-phosphate can be efficiently produced by controlling the ratio of substrates. When the conversion reaction is performed at pH4.5 under 40° C. for 8 h, the output of ascorbic acid-2-phosphate reaches 54.8 ?/L, the conversion is 42.9% and the space time yield is 6.9 g/L/h.

Abstract: A method and apparatus for implementing a virtual local area network. The method includes determining a global virtual local area network for transmitting a data frame in response to receiving the data frame at a first switch, encapsulating the data frame based at least in part on said determination and transmitting it to at least one second switch over the determined global virtual local area network. The data frame is received at the second switch and an identifier of the global virtual local area network is obtained according to the data frame. Based at least in part on the identifier of the global virtual local area network, it is determined that which local virtual local area network served by the second switch the de-capsulated data frame can be sent to.

Abstract: The present invention relates to data packet processing in a data network, and provides a method and system for processing data packets. The method comprising: dividing flows containing data packets into elephant flows and mice flows according to a particular division parameter, wherein, an elephant flow contains more data packets than a mice flow; transmitting the divided elephant flows and mice flows to a virtual switch in a server; processing the mice flows at the virtual switch, and transmitting the elephant flows and the processed mice flows to a hardware switch in network; and processing the elephant flows at the hardware switch, and forwarding the received mice flows and the processed elephant flows. With the method and system, network performance may be effectively improved.

Abstract: A method and apparatus for implementing a virtual local area network. The method includes determining a global virtual local area network for transmitting a data frame in response to receiving the data frame at a first switch, encapsulating the data frame based at least in part on said determination and transmitting it to at least one second switch over the determined global virtual local area network. The data frame is received at the second switch and an identifier of the global virtual local area network is obtained according to the data frame. Based at least in part on the identifier of the global virtual local area network, it is determined that which local virtual local area network served by the second switch the de-capsulated data frame can be sent to.

Abstract: Techniques for realizing service chaining, a corresponding apparatus and an SDN (Software Defined Network) controller are disclosed. The method includes temporarily modifying an original destination MAC (media access control) address of a packet and an original source MAC address the packet during the time the packet makes a hop from one middlebox to another. A restore operation is used to restore the original source and destination MAC addresses after the hop is made.

Abstract: A method for processing a resource access request in a network based on a software defined network (SDN) protocol includes receiving a resource access request forwarded by a first SDN switch in the network, wherein there exists no forwarding rule matching the resource access request in the first SDN switch; obtaining, according to the resource access request, resource server information of a resource server where the requested resource is stored, wherein the resource server is located in the network; generating a forwarding rule corresponding to the resource access request according to the resource server information; and sending to the first SDN switch at least one portion of the forwarding rule corresponding to the resource access request, so that the first SDN switch forwards the resource access request according to the at least one portion of the forwarding rule.

Abstract: A method and apparatus for performing network transfer adaptive optimization in a computing system. The method includes forming a message to be transferred through the network based on obtained information related to a task executed by computing nodes, wherein the message includes identification of the computing nodes to perform data transfer and corresponding sink nodes, and an amount of data the computing nodes to transfer to the corresponding sink nodes; transferring the message to a network layer; and forming a data transfer pattern for data transfer between the computing nodes and the corresponding sink nodes in accordance with the message.

Abstract: A method for processing a resource access request in a network based on a software defined network (SDN) protocol includes receiving a resource access request forwarded by a first SDN switch in the network, wherein there exists no forwarding rule matching the resource access request in the first SDN switch; obtaining, according to the resource access request, resource server information of a resource server where the requested resource is stored, wherein the resource server is located in the network; generating a forwarding rule corresponding to the resource access request according to the resource server information; and sending to the first SDN switch at least one portion of the forwarding rule corresponding to the resource access request, so that the first SDN switch forwards the resource access request according to the at least one portion of the forwarding rule.

Abstract: A method and apparatus for performing network transfer adaptive optimization in a computing system. The method includes forming a message to be transferred through the network based on obtained information related to a task executed by computing nodes, wherein the message includes identification of the computing nodes to perform data transfer and corresponding sink nodes, and an amount of data the computing nodes to transfer to the corresponding sink nodes; transferring the message to a network layer; and forming a data transfer pattern for data transfer between the computing nodes and the corresponding sink nodes in accordance with the message.

Abstract: The present invention relates to data packet processing in a data network, and provides a method and system for processing data packets. The method comprising: dividing flows containing data packets into elephant flows and mice flows according to a particular division parameter, wherein, an elephant flow contains more data packets than a mice flow; transmitting the divided elephant flows and mice flows to a virtual switch in a server; processing the mice flows at the virtual switch, and transmitting the elephant flows and the processed mice flows to a hardware switch in network; and processing the elephant flows at the hardware switch, and forwarding the received mice flows and the processed elephant flows. With the method and system, network performance may be effectively improved.

Abstract: A method and system for performing network transfer adaptive optimization in a large-scale parallel computing system. The method of network transfer adaptive optimization includes forming a message to be transferred through the network based on obtained information related to a task executed by computing nodes, wherein the message includes identification information of the computing nodes to perform data transfer and corresponding sink nodes, and an amount of data the computing nodes to transfer to the corresponding sink nodes; transferring the message to a network layer; and forming a new data transfer pattern for data transfer between the computing nodes and the corresponding sink nodes in accordance with the received message.

Abstract: Method, apparatus and system for resolving domain names in network. One embodiment provides a method for resolving a domain name in a network, including: receiving, at a controller associated with a switch in the network, a domain name system (DNS) request for the domain name from the switch, the DNS request initiated by a client, the controller controlling operations of the switch in the network; and controlling processing of the DNS request based on a predefined security constraint at the controller to obtain a network address corresponding to the domain name, wherein the DNS request is forwarded by the switch to the controller in response to a DNS record related to the domain name being missed in first storage at the switch. Other embodiments of the present invention provide a corresponding apparatus and system.

Abstract: Techniques for realizing service chaining, a corresponding apparatus and an SDN (Software Defined Network) controller are disclosed. The method includes temporarily modifying an original destination MAC (media access control) address of a packet and an original source MAC address the packet during the time the packet makes a hop from one middlebox to another. A restore operation is used to restore the original source and destination MAC addresses after the hop is made.