Source: http://www.google.com/patents/US8112517?dq=6,247,130
Timestamp: 2014-09-20 06:15:57
Document Index: 537175225

Matched Legal Cases: ['art 612', 'art 612', 'art 605', 'art 612', 'art 612', 'art 612', 'art 602', 'art 602', 'art 605', 'art 612', 'art 612', 'art 612', 'art 612']

Patent US8112517 - Relay system, relay program, and relay method - Google PatentsSearch Images Maps Play YouTube News Gmail Drive More »Sign in<nobr>Advanced Patent Search</nobr>PatentsA technique is provided to dynamically change priority, according to content of communication data, when the communication data is relayed between a client device and a host device. A communication gateway (102) is a relay system for relaying the communication data between a thin client device (101)...http://www.google.com/patents/US8112517?utm_source=gb-gplus-sharePatent US8112517 - Relay system, relay program, and relay methodAdvanced Patent SearchPublication numberUS8112517 B2Publication typeGrantApplication numberUS 12/022,225Publication dateFeb 7, 2012Filing dateJan 30, 2008Priority dateJan 30, 2007Also published asCN101237468A, CN101237468B, EP1965566A2, EP1965566A3, US20080215723Publication number022225, 12022225, US 8112517 B2, US 8112517B2, US-B2-8112517, US8112517 B2, US8112517B2InventorsYoshiteru Takeshima, Kazuya TsurutaOriginal AssigneeHitachi, Ltd.Export CitationBiBTeX, EndNote, RefManPatent Citations (5), Non-Patent Citations (1), Classifications (32), Legal Events (1) External Links: USPTO, USPTO Assignment, EspacenetRelay system, relay program, and relay methodUS 8112517 B2Abstract A technique is provided to dynamically change priority, according to content of communication data, when the communication data is relayed between a client device and a host device. A communication gateway (102) is a relay system for relaying the communication data between a thin client device (101) and the host device (103). The communication gateway (102) monitors communication performed by the host device (103) in response to a request from the thin client device (101). The communication gateway (120) determines priority of the communication that is returned to the client device by the host device (103) in response to the request, based on a protocol for the communication performed by the host device (103).
INCORPORATION BY REFERENCE This application claims priority based on a Japanese patent application, No. 2007-018848 filed on Jan. 30, 2007, the entire contents of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION The present invention relates to a technique to relay communication data between a client device and a host device.
In recent years, in corporate entities, information leakage due to loss or theft of notebook PCs is becoming a problem. As a way for solving this problem, there is an approach referred to as a �thin client system�. In the thin client system, a client device is provided with a minimum required function only, whereas a server (host device) integrally controls application software and electronic files. As one such thin client system, there is a system that is called as �screen transfer type thin client system�.
In order to improve the situation above, there is an approach for speeding up communication between the client device and the host device. Here, prioritized delivery by a router is taken as a measure for speeding up a particular network communication. This prioritized delivery is a technique in which a core router arranged in the Internet or an intranet transfers a particular communication flow packet, giving the packet a higher priority than other packets. This technique is utilized mainly to reduce transfer delay in a real-time communication application, such as video streaming and IP telephony. The core router that performs such prioritized delivery as described above is also referred to as QoS (Quality of Service) router. �Diffserv (Differentiated Services)� is taken as an example of a representative technique of such prioritized delivery. In simple terms, this technique involves setting a transfer priority to a header of a packet, and the core router performing the prioritized delivery according to the priority. The technique �Diffserv� is described in �S. Blake, et al. �An Architecture for Differentiated Services� [online], December 1998, (retrieved on Dec. 15, 2006), Internet URL: http://www.ietf.org/rfc/rfc2475.txt� (hereinafter, referred to as �non-patent document 1�).
SUMMARY OF THE INVENTION In view of the situation above, the present invention provides a technique to dynamically change the priority according to content of communication data, when the communication data is relayed between the client device and the host device.
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a functional block diagram of a communication gateway relating to an embodiment of the present invention;
DETAILED DESCRIPTION OF THE EMBODIMENTS FIG. 1 is a schematic diagram of a communication gateway 102 according to one embodiment of the present invention.
The delivery priority field 403 stores a value indicating a priority when data is transferred when there is a response to the thin client device 101 from the host device 103. Here, in the present embodiment, the value being stored in this field represents �normal� which specifies that the delivery is a normal delivery 131 and the prioritized delivery 132 by the Diffserv is not performed, or represents �high� which specifies that the delivery is the prioritized delivery 132 for performing the prioritized delivery 132 by the Diffserv.
The delivery priority field 512 stores information that identifies a priority in the communication using the port number specified in the port number field 511. Here, in the present embodiment, the delivery priority field 512 stores the text �normal� which specifies that the delivery is a normal delivery 131 and the prioritized delivery 132 by the Diffserv is not performed, or the text �high� which specifies that the delivery is the prioritized delivery 132 for performing the prioritized delivery 132 by the Diffserv. By way of example, the delivery priority 512, �normal�, is associated in advance with HTTP communication 122 (associated port number �80�) or the like, for which real-time communication is not required, and stored. Furthermore, the delivery priority 512, �high�, is associated in advance with real-time communication 123 (associated port number �554�) or the like, for which real-time communication is required, and stored.
In addition, when the coupling from the host device 103 to the thin client device 101 via the Internet 110 is detected, and if the IP address of the host device 103 as a source in the coupling is not stored in the coupling source field 401 of the outward coupling management table 400, the monitor 611 determines the information specifying priority as �normal�, and notifies the priority information addition part 612 about this information.
Therefore, upon receipt of the notification from the monitor 611, the priority information addition part 612 changes the value of the DSCP 708 to a value corresponding to the priority that is specified by the notification, or keeps the value unchanged. Here, by way of example, if the information specifying the priority indicates �normal�, the value of the DSCP 708 is set to �000000�, and if the information specifying the priority indicates �high�, the value of the DSCP 708 is set to �000001�.
Here, from the destination IP address in the received packet 700, it is determined that the coupling is with another device (steps S03 and S05). The controller 602 performs the process (step S06) to determine the delivery priority of the packet 700 that is passed from the interface 601 (step S109). Specifically, the monitor 611 in the controller 602 writes the source IP address 704, the source port 706, the destination IP address 705, and the destination port 707 within the packet 700, into the outward coupling management table 400 in the outward coupling storage unit 604. In addition, the monitor 611 extracts the delivery priority 512 associated with the destination port 707, from the service priority definitions information 500 stored in the service priority definition part 605. Since �80� is written in the destination port 707, the delivery priority 512 that has been extracted is �normal�. The monitor 611 writes the delivery priority 512 that has been extracted into the outward coupling management table 400, after making an association with previously written data (the source IP address 704, and the like).
On this occasion, the interface 601 of the communication gateway 102 passes the packet 700 received in step S113 to the controller 602 (steps S01 and S02). Then, it is determined that the communication is directed to the thin client device 101, according to the destination IP address in the received packet 700 (steps S03, S05 and S07). The priority information addition part 612 of the controller 602 firstly extracts the source IP address 704 within the packet 700. The priority information addition part 612 searches the IP address 411 in the outward coupling management table 400 for the IP address matching the source IP address 704 that has been extracted. Here, if a matching IP address is found, the priority information addition part 612 refers to the delivery priority 403 (�normal�), which is stored so as to be associated with the corresponding IP address 411. Subsequently, the priority information addition part 602 changes the value of DSCP 709 of the packet 700, according to the delivery priority 403 that is referred to, and passes the packet 700, which was changed, to the interface 601 (step S08) However, if it is not necessary to change the value of DSCP 709, the priority information addition part 602 may pass the packet 700 to the interface 601 without changing the value of DSCP 709.
Next, from the destination IP address in the received packet 700, it is determined that the coupling is directed to another device (steps S03 and S05). The controller 602 performs a process (step S06) to determine the delivery priority of the packet 700 passed from the interface 601 (step S209). Specifically, the monitor 611 in the controller 602 writes the source IP address 704, the source port 706, the destination IP address 705, and the destination port 707 within the packet 700, into the outward coupling management table 400 in the outward coupling storage unit 604. In addition, the monitor 611 extracts the delivery priority 512, associated with the destination port 707, from the service priority definitions information 500 stored in the service priority definition part 605. In this example here, since �554� is written in the destination port 707, the delivery priority 512 that is extracted is �high�. The monitor 611 writes the delivery priority 512 that has been extracted into the outward coupling management table 400, so as to make an association with previously written data (the source IP address 704, and the like).
On this occasion, the interface 601 of the communication gateway 102 passes the packet 700 received in step S213 to the controller 602 (steps S01 and S02). Then, it is determined that the communication is directed to the thin client device 101, according to the destination IP address in the received packet 700 (steps S03, S05 and S07). The priority information addition part 612 of the controller 602 firstly extracts the source IP address 704 within the packet 700. The priority information addition part 612 searches the IP address 411 in the outward coupling management table 400 for the IP address agreeing with the source IP address 704 that has been extracted. Here, if a matching IP address is found, the priority information addition part 612 refers to the delivery priority 403 (�high�), which is stored so as to make an association with the corresponding IP address 411. Subsequently, the priority information addition part 612 changes the value of DSCP 709 of the packet 700 according to the delivery priority 403 that is referred to (step S214), and passes the packet 700 that has been changed, to the interface 601 (step S08).
For example, in the embodiment described above, the delivery priority has two levels, �normal� and �high�. However, the present invention is not limited to this embodiment, and the delivery priority may have three or more levels, according to the protocol (communication service).
In the embodiment described above, the priority of a protocol used in the real-time communication is set to be �high�. However, the present invention is not limited to this embodiment, and according to the environment in which the communication system is applied, the priority stored in the service priority definition information 500 may be configured arbitrarily.
Patent CitationsCited PatentFiling datePublication dateApplicantTitleUS6546425 *Jun 11, 1999Apr 8, 2003Netmotion Wireless, Inc.Method and apparatus for providing mobile and other intermittent connectivity in a computing environmentUS6930984 *Dec 21, 1999Aug 16, 2005Fujitsu LimitedNetwork-device control system and apparatusUS7260635 *Feb 18, 2003Aug 21, 2007Centrisoft CorporationSoftware, systems and methods for managing a distributed networkUS7440456 *Jun 7, 2002Oct 21, 2008The Distribution Systems Research InstituteTerminal-to-terminal communication connection control system for IP full serviceWO2000060826A1Mar 31, 2000Oct 12, 2000Nortel Networks LtdPacket classifier and converter* Cited by examinerNon-Patent CitationsReference1 *S. Blake, et al., "An Architecture for Differentiated Services" [online], Dec. 1998, (retrieved on Dec. 15, 2006), Internet URL: http://www.ietf.org/rfc/rfc2475.txt.* Cited by examinerClassifications U.S. Classification709/224, 709/230, 709/223, 370/395.42, 709/220, 370/395.31, 370/395.5, 709/221, 370/351International ClassificationG06F15/173Cooperative ClassificationH04L65/103, H04L65/605, H04L65/80, H04L47/2458, H04L47/2433, H04L47/2491, H04L47/2416, H04L47/2408, H04L47/10, H04L69/22, H04L67/08European ClassificationH04L29/06M6C6, H04L29/06N, H04L29/06M8, H04L29/06M2N2M4, H04L29/08N7, H04L47/10, H04L47/24F, H04L47/24C1, H04L47/24K, H04L47/24A, H04L47/24BLegal EventsDateCodeEventDescriptionMay 12, 2008ASAssignmentEffective date: 20080131Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:TAKESHIMA, YOSHITERU;TSURUTA, KAZUYA;REEL/FRAME:020934/0590Owner name: HITACHI, LTD., JAPANRotateOriginal ImageGoogle Home - Sitemap - USPTO Bulk Downloads - Privacy Policy - Terms of Service - About Google Patents - Send FeedbackData provided by IFI CLAIMS Patent Services©2012 Google