JP2005064854A - Multiplexing method, apparatus and program using mobile ip - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a multiplexing method, an apparatus and a program for multiplexing a plurality of communication links suitable for a mobile IP. <P>SOLUTION: The multiplexing method includes a first step in which a first device sends a registration request containing a multiplexing present or absent flag and a multiplexing group identifier for each c/o address to a home agent address, a second step in which a second device sends a registration response for each registration request to the c/o address; a third step in which a first communication device delivers a packet to be sent to a plurality of communication means registered by the same multiplexing group identifier, and a fourth step in which a second communication device collects the packets received for the plurality of communication links registered by the same multiplexing group identifier. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a multiplexing method, apparatus, and program for multiplexing a plurality of communication links using mobile IP.

  A mobile device that is connected to the Internet wirelessly and is supposed to move is preferably provided with a plurality of communication media in order to use appropriate communication media according to the current location or communication environment. For example, a broadband wireless LAN communication means can be used if it is located at a short distance from the base station, and a narrow band mobile phone communication means can be used otherwise.

  Thus, for example, when it is necessary to use narrowband communication means, it is preferable to establish a plurality of communication links and treat them virtually as one communication link. In the Internet Engineering Task Force (IETF), MP (Multilink Protocol) is standardized as an option of LCP (Link Control Protocol) of PPP (Point to Point Protocol) (see, for example, “Non-patent Document 1”). Examples of the application of MP include a method of multiplexing wireless communication links over a wide area (see, for example, “Non-Patent Document 2”), a method of bundling two ISDN B channels (64 Kbps) and using them as a 128 Kbps line. is there.

  FIG. 1 is a system configuration diagram using a plurality of communication links for mobile IPv4.

  Specifically, a plurality of care-of addresses (CoA: Care of Address) acquired from each communication link by a mobile node (MN: Mobile Node) can be registered in a home agent (HA: Home Agent). Reference 3 ”). As a result, the communication link used for each IP connection can be switched by changing the care-of address CoA used according to the address or port number of the communication partner. In particular, according to FIG. 1, CN1 and MN can communicate with each other via a wireless LAN by HA, and CN2 and MN can communicate with each other via HA and a cellular phone network.

  FIG. 2 is a system configuration diagram for multiplexing a plurality of wireless communication links using a transport protocol.

  According to FIG. 2, a communication link via a wireless LAN and a communication link via a mobile phone network can be established by a transport protocol, and the plurality of communication links can be multiplexed and used (for example, “non-patent” Reference 3 ”).

K. Sklower et al., "The PPP Multilink Protocol (MP)", IETF RFC1990 A. Snoeren et al., “Adaptive Inverse Multiplexing for Wide-Area Wireless Networks”, In Proceeding of IEEE GlobeCom. Rio de Janeiro, December 1999. X. Zhao et al., “Flexible Network Support for Mobile Hosts, Mobile Networks and Applications (MONET)”, volume 6, number 2, March / April 2001 L. Magalhaes et al., “Transport Level Mechanisms for Bandwidth Aggregation on Mobile Hosts”, The 9th International Conference on Network Protocols (ICNP 2001), 2001.

  However, the conventional MP assumes that all communication links to be multiplexed are terminated between the same devices, and it is difficult to multiplex different types of communication links (for example, different care-of addresses). It was. Further, the method of Non-Patent Document 3 merely switches the communication link used for each IP connection, and it is impossible to simultaneously use the bands of a plurality of communication links with one IP connection. Further, according to Non-Patent Document 4, it is necessary to mount a transport protocol capable of multiplexing a plurality of wireless communication links in all apparatuses that perform communication, and it is difficult to apply to a real environment.

  Accordingly, it is an object of the present invention to provide a multiplexing method, apparatus and program for multiplexing a plurality of communication links suitable for mobile IP.

  The present invention uses a mobile IP between a first device having a plurality of communication means and a care-of address assigned to each communication means and a second device assigned a home agent address. The present invention relates to one that multiplexes a plurality of communication links.

According to the method of the present invention,
A first step in which a first device transmits, for each care-of address, a registration request including a multiplexing presence / absence flag and a multiplexing group identifier to a home agent address;
A second step in which the second device sends a registration response to the care-of address for each registration request;
The first or second communication device distributes the packet to be transmitted to a plurality of communication means registered by the same multiplexing group identifier, and the second or first communication device has the same multiplexing group identifier. And a third step of collecting received packets from a plurality of communication links registered by.

According to another embodiment of the method of the present invention,
For the first step, a communication enable / disable state and a communication band state in a plurality of communication means of the first device are detected, and a communication means that can be multiplexed based on the communication enable / disable state and the communication band state is selected. It is also preferable that the multiplexed group identifier of the registration request is the same for each selected communication means.

According to another embodiment of the method of the present invention,
For the first step, policy information in which weighting is defined for each communication means is previously stored, and a communication means that can be multiplexed based on the policy information, a communication enable / disable state, and a communication band state is selected. preferable.

According to another embodiment of the method of the present invention,
For the third step, the first communication device gives an order control flag to the packet to be transmitted,
Regarding the fourth step, it is also preferable that the second communication device controls the order of received packets.

According to another embodiment of the method of the present invention,
Preferably, the first device and the second device are mobile routers, and the communication means of the first device is a mobile phone communication means, a PHS communication means, and a wireless LAN communication means.

According to the device of the present invention,
Control means for controlling to send a registration request including a multiplexing presence / absence flag and a multiplexing group identifier for each care-of address to the home agent address;
Distribution means for distributing packets to be transmitted to a plurality of communication means registered by the same multiplexing group identifier;
And collecting means for collecting received packets from a plurality of communication links registered by the same multiplexing group identifier.

According to another embodiment of the device of the invention,
The control means detects communication enable / disable states and communication band states in a plurality of communication means, selects a communication means that can be multiplexed based on the communication enable / disable state and the communication band state, and selects each of the selected communication means. In addition, it is also preferable that the multiplexed group identifiers of the registration requests are the same.

According to another embodiment of the device of the invention,
It is also preferable that the control means has policy information in which weighting is defined for each communication means in advance, and a communication means that can be multiplexed is selected based on the policy information, the communication enable / disable state, and the communication bandwidth state.

According to another embodiment of the device of the invention,
The distribution means adds an order control flag to the packet to be transmitted,
The collecting means also preferably performs order control of received packets.

According to another embodiment of the device of the invention,
The apparatus is preferably a mobile router, and the communication means is preferably a mobile phone communication means, a PHS communication means, and a wireless LAN communication means.

According to the program of the present invention,
Control means for controlling to send a registration request including a multiplexing presence / absence flag and a multiplexing group identifier for each care-of address to the home agent address;
Distribution means for distributing packets to be transmitted from a plurality of communication means registered by the same multiplexing group identifier;
A computer is caused to function as a collecting unit for collecting received packets to a plurality of communication links registered by the same multiplexing group identifier.

According to another embodiment of the program of the present invention,
The control means detects communication enable / disable states and communication band states in a plurality of communication means, selects a communication means that can be multiplexed based on the communication enable / disable state and the communication band state, and selects each of the selected communication means. In addition, it is also preferable to cause the computer to function so that the multiplexed group identifiers in the registration request are the same.

According to another embodiment of the program of the present invention,
The control means has policy information in which a weight is defined for each communication means in advance, and the computer is selected so that a communication means that can be multiplexed is selected based on the policy information, the communication enable / disable state, and the communication bandwidth state. It is also preferable to make it function.

According to another embodiment of the program of the present invention,
The distribution means adds an order control flag to the packet to be transmitted,
The collecting means preferably causes the computer to function to control the order of received packets.

According to another embodiment of the program of the present invention,
Preferably, the apparatus is a mobile router, and the communication means is a mobile phone communication means, a PHS communication means, and a wireless LAN communication means.

  According to the present invention, not only a relatively narrowband communication link such as a mobile phone communication means, but also a wideband can be used by multiplexing a plurality of communication links. Because the communication link is terminated for each care-of address, it does not depend on the position of the device. Further, according to the present invention, it is easy to extend the multiplexing function with respect to the mobile IP. Furthermore, according to the present invention, a plurality of communication links can be dynamically switched, and communication links can be selected according to the situation. In particular, when the present invention is applied to a mobile router for mobile IP, a node on the MNW that changes a connection point with an external network does not need to have an implementation for multiplexing communication links.

  FIG. 3 is a system configuration diagram according to the present invention.

  According to FIG. 3, MR that can communicate with SN (Stationary Node) 3 and HA-MR (Home Agent-Mobile Router) 2 that can communicate with CN (Correspondent Node) 4 are connected via Internet 5. ing. MR1 is a LAN port 11 that communicates with SN3, mobile IP control means 12, packet scheduler 13, order control means 14, PPP control means 150-15n, mobile phone communication means 160-16n, and PHS communication means. 17, wireless LAN communication means 18, and media switching means 19. Since MR1 has various communication media, it is possible to select an optimal communication means according to the location.

  Here, FIG. 3 is characterized in that it has a plurality of mobile phone communication means 160 to 16n. In other words, the communication band of the mobile phone communication means is extremely narrow compared with the communication band of the wireless LAN, but by assembling a plurality of communication links for mobile phone communication, an attempt is made to secure a broadband communication link as much as possible. There are features.

  The mobile IP control means 12 performs mobile IP communication protocol control. The packet scheduler 13 distributes the packets to be multiplexed with respect to the packets to be transmitted to the HA-MR. At this time, the packet scheduler 13 adds a flag (for example, sequence number) for order control to each distributed packet. On the other hand, the order control means 14 arranges the packets received from the communication links in the order of the sequence numbers. This is because the transmission delay differs depending on the communication link, so that the order of packets transmitted and received on different communication links may be reversed.

  The PPP means 150 to 15n control PPP, and here, two-point data communication is realized so that the mobile phone communication means 16 can use IP. Mobile phone communication means 160 to 16n, which are communication means, are connected to the Internet 5 via a mobile phone network. Here, the mobile phone communication means 160 to 16n have their own care-of addresses CoAp0 to CoApn, and communicate with the LAN port of the HA-MR 2 via the Internet 5. The PHS communication means 17 and the wireless LAN communication means 18 that are communication means also have unique care-of addresses.

  The media switching control means 19 detects the communication enable / disable state and the communication band state for each communication means 16, 17 and 18, and selects the communication means that can be multiplexed based on the communication enable / disable state and the communication band state. For each selected communication means, the multiplexed group identifier of the registration request is the same. For example, when the wireless LAN communication unit 18 and the mobile phone communication unit 16 can communicate and the wireless LAN communication unit 18 is preferentially used, the wireless LAN communication unit 18 cannot communicate depending on the position of the MR1. The media switching control means 19 controls to switch to the mobile phone communication means 16. Further, for example, when a plurality of mobile phone communication means 16 are multiplexed and used, when the communication band state of any one of the mobile phone communication means 16 deteriorates, the mobile phone communication means 16 is added to the multiplexed group. Control to remove from. At this time, the media switching control means 19 uses the mobile phone communication means 16 other than the removed mobile phone communication means 16 to notify the counterpart HA-MR 2 that the mobile phone communication means 16 is removed. Thereby, the HA-MR 2 can also remove the mobile phone communication means 16 from the multiplexed group.

  In particular, a communication unit that has policy information in which weighting is defined for each communication unit in advance and can be multiplexed based on the policy information, a communication enable / disable state, and a communication band state is selected. For example, when the wireless LAN communication unit 18 and the mobile phone communication unit 16 can communicate, it is preferable to preferentially select the wireless LAN communication unit 18. Note that the communication means may be selected in order as simply round robin.

  Further, the media switching control means 19 always detects the communication band. For example, when communication by the wireless LAN communication means becomes impossible, the media switching control means 19 establishes a communication link to the plurality of PPP means 15 and the mobile phone communication means 16. Can be directed to.

  Each of the mobile phone communication units 160 to 16n transmits a registration request message to the HA-MR 2. The care-of address of each communication unit is added to the registration request message as a transmission source, and the “multiplexing flag” is set to “multiplex”. "Multiple group identifier" is the same. The communication link to be multiplexed becomes clear, and the packet scheduler 13 distributes the packet to communication links having the same “multiplexing group identifier”.

  In addition, according to FIG. 3 mentioned above and FIG. 4 demonstrated below, although the multiplexing communication link between MR and HA-MR is described, the multiplexing link between MN and HA-MN is described. The same can be realized in the same way.

  FIG. 4 is a sequence diagram according to the present invention.

(S1) Registration of care-of address MR-CoA1 of IF1 to Ifn

  When the MR determines that the communication link needs to be multiplexed, the MR establishes an IP tunnel with the HA-MR for each communication link to be multiplexed. At this time, the MR uses a care-of address MR-CoAk (each communication link k: 1 to n) for each communication link. The MR transmits a registration request message of MR-CoAk-> HA-MR to the HA-MR for each communication link IFk (k: 1 to n) (mobile phone communication means according to FIG. 3).

  The registration request message normally includes a combination of MR-HoA, MNW (Mobile Network) and MR-CoAk, but according to the present invention, it further includes a “multiplexing presence / absence flag” and a “multiplexing group identifier”. . Such expansion can be easily realized for mobile IP, for example. When the multiplexing presence / absence flag is “with multiplexing”, it is determined that a plurality of communication links indicated by the same multiplexing flag identifier are multiplexed.

  The HA-MR that has received this registration request message holds the combination of MR-HoA, MNW, and MR-CoAk, and returns a registration response message of HA-MR-> MR-CoAk to MR-CoAk for each communication link. . In this way, the registration request message and the registration response message are exchanged for each communication link that performs multiplexing of MR.

(S2) Communication between CN and SN (IF1 to IFn are multiplexed)

  The MR receives a packet of SN-> CN transmitted by the SN. MR selects whether or not to use the multiplexed communication link established in S1 based on the communication state of each communication means. When the multiplexed communication link is used, the MR distributes the SN-> CN packet to each communication link for each care-of address MR-CoAk, and encapsulates it in MR-CoAk-> HA-MR. In response to this, the HA-MR releases the encapsulation of the packet received from the MR, and transmits a packet of SN-> CN to the CN.

  On the other hand, a packet of CN-> SN transmitted by the CN is received by the HA-MR. The HA-MR distributes the packet of CN-> SN to each communication link for each care-of address MR-CoAk, encapsulates it with HA-MR-> MR-CoAk, and transmits it. In response to this, the MR releases the encapsulation of the packet received from the HA-MR, and transmits a packet of CN-> SN to the SN.

(S3) Deregistration of IF care-of address MR-CoA1

  When the multiplexed communication link becomes unavailable for some reason, the MR transmits a registration request message with the validity time set to 0 to the HA-MR in order to delete the registration. This registration request message is transmitted from a communication link other than the communication link whose registration is to be deleted. Referring to FIG. 4, if the communication link of IF1 becomes unavailable, the MR sends a registration request message notifying the combination of MR-HoA, MNW, and MR-CoA1 that has entered 0 as the valid time to an IF other than IF1. To HA-MR. When HA-MR receives the registration request message, HA-MR deletes the combination of MR-HoA, MNW, and MR-CoA1, and tunnels the packet addressed to the address included in the address prefix of MR-HoA and MNW. Remove from the subject.

(S4) Communication between CN and SN (IF2 to IFn are multiplexed)

  The MR receives a packet of SN-> CN transmitted by the SN. The MR distributes the packet for SN-> CN to the MR-CoAk communication link other than the care-of address MR-CoA1, encapsulates it with HA-MR-> MR-CoAk, and transmits it. On the other hand, the HA-MR releases the encapsulation of the packet received from the MR, and transmits the SN-> CN packet to the SN.

  On the other hand, a packet of CN-> SN transmitted by the CN is received by the HA-MR. The HA-MR distributes the packet of CN-> SN to each communication link of MR-CoAk other than the care-of address MR-CoA1, and encapsulates it with HA-MR-> MR-CoAk for transmission. In response to this, the MR releases the encapsulation of the packet received from the HA-MR, and transmits a packet of CN-> SN to the SN.

  It is also possible to switch between a plurality of multiplexed communication links and another single communication link. For example, if the available communication link among the communication links to be multiplexed in MR is equal to or greater than the threshold value T1, it is determined that multiplexing is possible, and multiplexing processing is started. On the other hand, when the usable communication link among the communication links to be multiplexed in the MR is equal to or less than the threshold value T2, it is determined that the multiplexing is impossible, and another available single communication link is used.

  The present invention is applied to a multiplexed communication link between MR and HA-MR or a multiplexed link between MN and HA-MN.

It is a system block diagram using a some communication link about Mobile IPv4. 1 is a system configuration diagram for multiplexing a plurality of wireless communication links using a transport protocol. FIG. 1 is a system configuration diagram according to the present invention. It is a sequence diagram by the present invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Mobile router 11 LAN port 12 Mobile IP control means 13 Packet scheduler 14 Order control means 150-15n PPP means 160-16n Mobile phone communication means 17 PHS communication means 18 Wireless LAN communication means 19 Media switching means 2 Home agent-mobile router 3 Fixed node 4 Counterpart node 5 Internet

Claims (15)

A plurality of communication links using a mobile IP between a first device having a plurality of communication means and a care-of address assigned to each communication means and a second device assigned a home agent address A multiplexing method for multiplexing
A first step in which the first device transmits a registration request including a multiplexing presence / absence flag and a multiplexing group identifier to the home agent address for each care-of address;
A second step in which the second device transmits a registration response to the care-of address for each registration request;
The first or second communication device distributes a packet to be transmitted to a plurality of communication means registered by the same multiplexing group identifier, and the second or first communication device uses the same multiplexing And a third step of collecting received packets from a plurality of communication links registered by a group identifier.   A communication means capable of detecting communication enable / disable states and communication band states in the plurality of communication means of the first device and multiplexing based on the communication enable / disable states and the communication band states for the first step; 2. The method according to claim 1, wherein the multiplexing group identifier of the registration request is the same for each selected communication means selected.   For the first step, there is selected in advance a communication means that has policy information in which a weight is defined for each communication means, and that can be multiplexed based on the policy information, the communication availability state and the communication band state. 3. The method of claim 2, wherein: For the third step, the first communication device gives an order control flag to a packet to be transmitted,
The method according to claim 1, wherein the second communication apparatus performs order control of received packets for the fourth step.   The first device and the second device are mobile routers, and the communication means of the first device is mobile phone communication means, PHS communication means, and wireless LAN communication means. Item 5. The method according to any one of Items 1 to 4. An apparatus that multiplexes a plurality of communication links using a mobile IP with a communication device that has a plurality of communication means, and a care-of address is assigned to each communication means. There,
Control means for controlling to send a registration request including a multiplexing presence / absence flag and a multiplexing group identifier for each care-of address to the home agent address;
Distribution means for distributing packets to be transmitted to a plurality of communication means registered by the same multiplexing group identifier;
And a collecting means for collecting received packets from a plurality of communication links registered by the same multiplexing group identifier.   The control means detects a communication availability state and a communication band state in the plurality of communication means, selects a communication means that can be multiplexed based on the communication availability state and the communication band state, and selects the selected communication The apparatus according to claim 6, wherein the multiplexing group identifier of the registration request is the same for each means.   The control means has policy information in which weighting is defined for each communication means in advance, and a communication means that can be multiplexed is selected based on the policy information, the communication availability state and the communication band state. The apparatus according to claim 7. The distribution means gives an order control flag to a packet to be transmitted,
The apparatus according to claim 6, wherein the collection unit performs order control of received packets.   The device according to claim 6, wherein the device is a mobile router, and the communication unit is a mobile phone communication unit, a PHS communication unit, and a wireless LAN communication unit. A device that has a plurality of communication means, has a care-of address assigned to each communication means, and multiplexes a plurality of communication links using a mobile IP with a counterpart device to which a home agent address is assigned. A controlling program,
Control means for controlling to send a registration request including a multiplexing presence / absence flag and a multiplexing group identifier for each care-of address to the home agent address;
Distribution means for distributing packets to be transmitted to a plurality of communication means registered by the same multiplexing group identifier;
A program for causing a computer to function as a collecting means for collecting received packets from a plurality of communication links registered by the same multiplexed group identifier.   The control means detects a communication availability state and a communication band state in the plurality of communication means, selects a communication means that can be multiplexed based on the communication availability state and the communication band state, and selects the selected communication 12. The program according to claim 11, wherein the computer is caused to function so that the multiplexed group identifier of the registration request is the same for each means.   The control means has policy information in which weighting is defined for each communication means in advance, and a communication means that can be multiplexed is selected based on the policy information, the communication availability state and the communication band state. The program according to claim 12, which causes a computer to function as described above. The distribution means gives an order control flag to a packet to be transmitted,
The program according to any one of claims 11 to 13, wherein the collection unit causes a computer to perform order control of received packets.   15. The computer according to claim 11, wherein the apparatus is a mobile router, and the communication unit causes the computer to function as a mobile phone communication unit, a PHS communication unit, and a wireless LAN communication unit. The program described in.

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