JP2003209890A - Mobile communication method and mobile communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent packet loss by suppressing transfer from a home agent during hand-over of a mobile station. <P>SOLUTION: In the communication method for a network comprising at least a mobile station and a home agent (HA) and using a mobile IP, the mobile station transmits a communication disabled period start telegraphic message to the HA when the communication disabled period is recognized, the HA receiving the communication disabled period start telegraphic message received by the HA on behalf of the mobile station stores IP packets addressed to the mobile station, when the communication disabled period is finished, the mobile station transmits a communication disabled period end telegraphic message to the HA, the HA receiving the communication disabled period end telegraphic message transfers the stored IP packets addressed to the mobile station to the mobile station, and the mobile station applies reception processing to the IP packets transferred from the HA. Thus, the efficient mobile communication system reducing the packet loss can be realized. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mobile communication method and a mobile communication system for improving the efficiency of handover of mobiles in a network using mobile IP.

[0002]

2. Description of the Related Art Currently, mobile IP technology centering on Mobile IP is under development. Mobile
Since IP operates in both IPv4 and IPv6, it is being studied for practical use such as being taken up by next-generation mobile phones and the like. R for Mobile IPv4
For FC2002 and Mobile IPv6, draft-ietf-mobileip-i
See pv6.

In practical use of Mobile IP, it is often applied to mobile phones, wireless LANs, etc. due to its mobility, but these are all systems having a cell structure with overlapping wireless zones, and subnets. Faster CoA (Care of Address) registration (Bind
ing Update) will be an issue. On the other hand, DSRC, which is a communication method used in an automatic charge collection system (ETC), etc.
In (Dedicated Short Range Communication), wireless zones are often arranged intermittently, and the problem is to suppress packet loss rather than high-speed CoA registration during subnet transfer.

Further, in a software defined wireless terminal in which the terminal can dynamically update its operating program, especially a module relating to wireless communication processing, the communication is disabled after the program is reconfigured after being acquired by means such as downloading. It is relatively long and equivalently needs to overcome the same challenges as DSRC. That is, how to prevent packet loss during program update is a major issue.

[0005]

The above-mentioned Mobile I
Among the problems in P, the present invention is to solve the problems related to packet loss, and it is an object of the present invention to reduce the packet loss that occurs during handover in wireless communication.

In Mobile IP, when the sender does not know the CoA of the mobile station, an IP packet is sent to the home address. When the mobile station does not exist in the home network (the home agent exists and the network to which the home address belongs), the home agent receives the IP packet by proxy and transfers it to the CoA of the mobile station registered in the home agent at that time. To do. When the mobile station cannot receive the IP packet transferred from the home agent during the handover period, the IP packet is eventually discarded.

Another object of the present invention is to suppress packet loss by suppressing transfer from the home agent during handover of the mobile station as described above.

[0008]

In order to solve the above problems, the present invention temporarily transfers an IP packet addressed to a mobile station during handover to a home agent to which the mobile station belongs and moves from the home agent at the same time as the handover is completed. It is designed to be transferred to the station.

As a result, according to the present invention, it is possible to reduce packet loss, reduce the communication load on the mobile station apparatus, and realize an efficient mobile communication system.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION According to the invention described in claim 1 of the present invention, in a communication method of a network using a mobile IP including at least a mobile station and a home agent, the mobile station may be in a communication incapable period. When it becomes clear, a communication deadline start message is sent to the home agent, and the home agent receiving the communication deadline start message accumulates IP packets addressed to the mobile station to be received by proxy thereafter, and the mobile station communicates. At the end of the unavailable period, a communication unavailable period end message is sent to the home agent, and the home agent receiving the communication unavailable period end message transfers the IP packet addressed to the mobile station,
The mobile station is characterized by receiving and processing the IP packet transferred from the home agent, without discarding the IP packet addressed to the mobile station, which should be originally received during the communication incompatibility period of the mobile station due to handover or the like. , And has the effect of delivering to the mobile station at the end of the incommunicable period. Here, when notifying the home agent of the new mobile station CoA after moving, the Mobile IP
The binding update message stipulated in the above may be used, or a new C message may be added to the communication end period message.
oA may be included.

Here, the incommunicable period start message and the incommunicable period end message may be those to which a binding update message is applied. For example, the incommunicable period start message is a CoA that is notified using a binding update message. A special value (for example, all zeros) may be set, or the CoA to be notified of the incommunicable period end message may be set to the CoA at which communication is possible (after movement). Both the incommunicable period start message and the incommunicable period end message to which the binding update message is applied may be superimposed on the data traffic by piggyback. Alternatively, the communication unavailable period start message and the communication unavailable period end message may be IP packets processed by a layer higher than the IP layer.

The invention according to claim 2 is characterized in that, in the mobile communication method according to claim 1, the home agent returns a response telegram to the telegram for starting the incommunicable period. If the home agent does not have the ability to store IP packets addressed to the mobile station (for example, the memory capacity is insufficient), or if the packet storage is rejected for some other reason, the mobile station that has sent the incommunicable period start message will On the other hand, it has the effect of being able to return a response message indicating a rejection response.

Here, the response message may be an application of the binding acknowledge message, and in that case, the response message may be superimposed on the data traffic by piggyback. Alternatively, the response message may be an IP packet processed in a layer above the IP layer.

The invention according to claim 3 is characterized in that, in the mobile communication method according to claim 1 or 2, the information regarding the estimated incommunicable time is included in the incommunicable period start message. This has the effect that the agent can predict the total amount of IP packets addressed to the mobile station in the future. Furthermore, depending on the total amount, a response message indicating storage refusal may be returned as the response message.

The invention according to a fourth aspect is the first to the third aspects.
In the mobile communication method according to any one of 1, the mobile station, at the time when it is clear that it will be in the incommunicable period,
Further, when the communication partner receives the communication-disabled period start message to the communication partner, and the communication partner receives the communication-disabled period start message, the communication partner sends an IP packet addressed to the mobile station to the home address of the mobile station. The mobile station can request that all the IP packets transmitted by the communication partner be transmitted to the home network during the incommunicable period.
As a result, the home agent accumulates the IP packet addressed to the mobile station after proxy reception, and later transfers it to the mobile station at the end of the incommunicable period.

At the end of the incommunicable period, the mobile station may explicitly issue the incommunicable period end message to the communication partner who has issued the incommunicable period start message. Directly to the mobile station CoA
P packets may be transmitted.

Here, the incommunicable period start message and the incommunicable period end message may be those to which a binding update message is applied. For example, the incommunicable period start message is a CoA notified by using a binding update message. A special value (for example, an IP address in which all bits are zero) is set, or a CoA that can be communicated at that time (after moving) is used as an CoA for notifying the incommunicable period end message.
It may be set by using the A sub-option.

The invention described in claim 5 is the invention according to claims 1 to 4.
In the mobile communication method according to any one of 1, the mobile station, at the time when it is clear that it will be in the incommunicable period,
In addition, it sends a communication message to start communication with the base station,
The base station is characterized by processing and transmitting the IP packet header addressed to the mobile station that has entered the incommunicable period, and regarding the IP packet header destined for the CoA of the mobile station, the destination is the mobile station. By changing to the home address, the IP packet addressed to the mobile station can be transferred to the home agent, and the IP packet that is originally discarded due to non-delivery to the mobile station can be rescued. For example, when the routing header is used, the base station performs the process of defining the destination address of the IP header as the home address described in the routing header by performing the process specified for the routing header.

The invention according to claim 6 is the same as claims 1 to 5.
In any one of the mobile communication methods described above, the home agent performs a protocol process so that the IP packet addressed to the mobile station, which is received by the proxy after receiving the incommunicable period start message, can be stored in an upper layer or in application data units. With respect to the IP packet addressed to the mobile station that is transferred to the home agent during the communication failure period of the mobile station, the home agent temporarily takes over the upper layer or application processing, and the appropriate data unit is By accumulating at the time of completion, the mobile station can smoothly resume the subsequent data communication.

In particular, in a data request type application using TCP, a series of data can be obtained without activating the congestion control of TCP, which leads to a substantial improvement in efficiency.

The invention according to claim 7 transmits a communication-disabled period start message to the home agent when it becomes clear that the communication-disabled period is reached, and communication is disabled when the communication-disabled period ends. It comprises means for transmitting a period end message to the home agent, and means for receiving and processing the IP packet transferred from the home agent after the communication disabled period message is transmitted. It is possible to reduce the packet loss by requesting the home agent to temporarily store the IP packet addressed to the mobile station, which should be originally received, and having the home agent transfer the IP packet at the end of the handover, that is, when the reception is restarted. It has the effect of being able to.

According to an eighth aspect of the invention, means for receiving and processing a communication-disabled period start message from a mobile station, means for accumulating IP packets addressed to the mobile station that have entered the communication-disabled period after proxy reception, and mobile And a means for transferring to the mobile station the IP packet addressed to the mobile station, which has been stored in advance, when receiving the end-of-communications period telegram from the station. The handover period in which the mobile station has declared the IP packet addressed to the mobile station. By temporarily storing after proxy reception and storing the IP packet to the new CoA of the mobile station as soon as the handover is completed, the mobile station is originally discarded because it is in the handover period. This has the effect of being able to rescue the IP packet that was in the vicinity.

According to a ninth aspect of the present invention, in the home agent device according to the eighth aspect, after receiving the communication-disabled period start message, an IP packet addressed to the mobile station that has entered the communication-disabled period is received by proxy. It is characterized by comprising means for performing protocol processing so that data can be stored in upper layers or application data units. This has the effect of reducing the reception load of.

The invention according to a tenth aspect is the mobile communication method according to any one of the first to sixth aspects, wherein the mobile station is a software defined radio device capable of dynamically updating its operation program. In the update, the communication deadline start message is sent to the home agent, and the communication deadline end message is sent to the home agent when communication becomes possible after the program update is completed. Similarly, there is an effect that it is possible to reduce the packet loss addressed to the mobile station during the operation program update period corresponding to the incommunicable period.

The invention described in claim 11 is a software defined radio device capable of dynamically updating an operation program, and means for transmitting a communication dead period start message to a home agent device when updating the program, and a program. And a means for transmitting an incommunicable period end telegram to the home agent device when communication becomes possible after the update is completed. The home agent device is requested to temporarily store the data, and the IP packet is transferred from the home agent device when the program is updated, that is, when the reception is restarted, so that packet loss can be reduced.

The invention described in claim 12 is a mobile communication system comprising the home agent device according to claim 8 or 9 and the mobile station device according to claim 7 or 11, and is used for handover and operation program update. There is an effect that an IP packet addressed to a mobile station, which should be originally received, is prevented from being lost during the resulting incommunicable period, and an efficient mobile communication system can be realized.

The invention according to claim 13 is the mobile communication method according to any one of claims 1 to 6 and 10, wherein the mobile station is absent after communication with a new base station becomes possible. The base station that transmits the temporary transfer request message to the base station and receives the unattended transfer request message receives the IP packet addressed to the mobile station by proxy when the communication with the mobile station is lost after that. It is characterized by processing the header and transmitting it, and even when the mobile station cannot communicate with the base station due to an unexpected handover,
The base station can detect the unreachability of the packet to the mobile station and can transfer the IP packet addressed to the mobile station to the home agent, and the IP that is originally discarded due to the failure to reach the mobile station.
This has the effect of being able to rescue the packet.

The invention according to claim 14 is, in the mobile station apparatus according to claim 7 or 11, that transmits an out-of-office transfer request message to the base station after communication with a new base station becomes possible. This has the effect of being able to reliably avoid IP packet loss due to the inability to communicate with the base station due to an unexpected handover.

According to a fifteenth aspect of the present invention, a means for receiving an unattended transfer request message from a mobile station and, when communication with the mobile station is lost thereafter, an IP packet addressed to the mobile station is received by proxy. Means and means for processing the header of the IP packet received by proxy and sending it out. Even when the mobile station cannot communicate with the mobile station due to an unexpected handover, it is addressed to the mobile station. IP
Packets can be forwarded to the home agent,
It has the effect of being able to rescue an IP packet that is originally discarded due to non-delivery to the mobile station.

According to a sixteenth aspect of the present invention, means for receiving and processing a communication-disabled period start message from a mobile station, means for receiving an IP packet addressed to a mobile station that has entered the communication-disabled period by proxy, and received by proxy. And a means for processing the header of an IP packet and transmitting the header. By changing the destination to the home address of the mobile station with respect to the IP packet header destined for the CoA of the mobile station, The IP packet addressed to the mobile station can be transferred to the home agent, and the IP packet that is originally discarded due to non-delivery to the mobile station can be rescued. For example, when the routing header is used, the base station performs the process of defining the destination address of the IP header as the home address described in the routing header by performing the process specified for the routing header.

According to the seventeenth aspect of the present invention, the communication between the means for receiving the unattended transfer request message and the incommunicable period start message from the mobile station and the communication with the mobile station after receiving the unattended transfer request message are interrupted. At the time of receiving a communication-disabled period start message from the mobile station, means for receiving the IP packet addressed to the mobile station by proxy and means for processing the header of the IP packet received by proxy and sending it out. This is a feature of the mobile station, which can transfer IP packets addressed to the mobile station to the home agent when the mobile station explicitly instructs it or when it cannot communicate with the mobile station due to an unexpected handover. This has the effect of being able to rescue an IP packet that is discarded due to a failure to reach the station.

The invention described in claim 18 is the home agent device according to claim 8 or 9, the mobile station device according to any one of claims 14 to 16, and the mobile station device according to claims 17 to 1.
9. A mobile communication system comprising the base station device according to any one of 9 to 9 above, which prevents loss of an IP packet addressed to a mobile station, which should be originally received during a communication unavailable period caused by a handover or an operation program update, It has an effect that an efficient mobile communication system can be realized. In particular, the mobile station does not need to request the communication partner to interrupt the communication by using a communication deadline start message or binding update.

The invention as set forth in claim 19 is characterized in that, in the mobile station apparatus as set forth in claim 7 or 11, a message for starting a communication incapable period is further transmitted to a communication partner. By moving the IP packet addressed to the mobile station transmitted from the CoA from the CoA address to the home address, it is possible to rescue the IP packet that was originally discarded due to non-delivery to the mobile station. .

The invention according to claim 20 is characterized in that, in the mobile station apparatus according to claim 14, a communication-disabling period start message is further transmitted to a communication partner. Not only when it is instructed, but also when it becomes impossible to communicate with the base station due to an unexpected handover, by making the IP packet addressed to the mobile station transmitted by the communication partner from the CoA address until then to the home address, Discarded due to failure to reach mobile station I
It has an effect that the P packet can be rescued.

The invention as set forth in claim 21 comprises means for receiving and processing a communication-disabled period start message, and means for transmitting an IP packet addressed to a mobile station that has entered the communication-disabled period to the home address of the mobile station. IP packet can be transmitted even during a packet undelivered period due to the destination mobile station performing a handover or updating the operation program, and the packet transmission can be continued to a well-defined place. As a result, the processing efficiency can be improved.

The invention described in claim 22 is a mobile communication system comprising the home agent device according to claim 8 or 9, the mobile station device according to claim 19, and the communication device according to claim 21. , By detecting that the communication device that is the source of the packet does not reach the mobile station, and by setting the subsequent IP packet addressed to the mobile station as the home address, the relay node (eg, base station) does not intervene. IP
The mobile communication system can eliminate the packet loss.

The invention described in claim 23 is the home agent apparatus according to claim 8 or 9, the mobile station apparatus according to claim 20, the base station apparatus according to any one of claims 15 to 17, Item 21. A mobile communication system comprising the communication device according to item 21, wherein when a packet non-delivery to a mobile station is detected and subsequent IP packets addressed to the mobile station are addressed to the home address, the communication device and IP for mobile station
When communication devices that continue to transmit packets to CoA are mixed, the base station supports the latter to realize a mobile communication system that can eliminate packet loss when the mobile station cannot communicate. Have.

An embodiment of the present invention will be described below with reference to the drawings.

(Embodiment 1) FIGS. 1 to 4, 7, 8, 15 to 19, 21, regarding a first embodiment of the present invention,
22 and 24 will be described.

FIG. 19 is a diagram showing an example of the configuration of a mobile communication system according to the first embodiment of the present invention, which is a mobile station device (in-vehicle terminal) 50 mounted on a vehicle and a roadside device 70.
-1, 70-2 shows the application regarding the road-vehicle communication system which performs wireless communication.

The roadside device 70-1 forms the radio zone 13 and the roadside device 70-2 forms the radio zone 23 to perform radio communication with the mobile station device 50 that has entered. In addition, the roadside device 70-
1 and 70-2 are networks 1 such as the Internet
Is directly or indirectly connected to the network 1. Similarly, the home agent apparatus 30 accommodating the mobile station apparatus 50 is directly or indirectly connected to the network 1.

The direct connection to the network 1 means that the roadside devices 70-1 and 70-2 operate as routers, and the indirect connection means the roadside devices 70-1 and 70- via the roadside network. Connected to network 1 via a router other than 2 (in this case, network 1
Is shown as including a router).

FIG. 21 is a diagram showing an example of a specific format of the communication-disabled period start message. An identifier field (code: 1 byte) 210 indicating that the IP packet is a communication disabled period start message, an expected communication disabled period field (supposed sleep time: 16 bytes) 212, a CoA field 214 and a home address field 213.
Consists of.

FIG. 22 is a diagram showing an example of a specific format of the telecommunications period end message. The IP packet includes an identifier field (code: 1 byte) 220 indicating that the IP packet is a communication disabled period start message, a CoA field 223, and a home address field 222. In addition,
At least one of the CoA field and the home address field may be provided.

The configurations of the mobile station device 50 and the home agent device 30 of the mobile communication system in FIG. 19 will be described below.

FIG. 1 is a diagram showing a first configuration example of the home agent device 30. Home agent device 30
Is directly or indirectly connected to the network 1, and specifically, the communication interface unit 31 executes the connection process of the second layer and below. The IP packet received by the communication interface unit 31 is transferred to the IP processing unit 32, where it is processed in accordance with Internet protocol regulations. When the received packet includes a message relating to mobile IP, it is transferred or notified to the mobile IP processing unit 33, for example, Mobile I which is one of the mobile IP methods.
The processing based on the regulation of P is performed. Further, when the communication-disabled period start message or the communication-disabled period end message from the mobile station device 50 is received, the control message processing unit 34.
The control unit 39 performs processing according to the procedure described later.

At this time, the accumulating unit 37 sends I to the mobile station device 50.
Accumulate P packets. When the home agent device 30 transmits a message related to mobile IP, the IP packet generated by the mobile IP processing unit 33 is transferred to the IP processing unit 32 and the communication interface unit 31 in this order to perform the transmission process.

Here, when the home agent device 30 is a router, it may have a plurality of communication interface units 31, but since the router processing is performed by the IP processing unit 32, the components shown in FIG. It is possible.

FIG. 2 is a diagram showing a second example of the configuration of the home agent apparatus 30. Explaining only the points different from FIG. 1, an upper layer processing section 35 is connected to the IP processing section 32, and further an application processing section. 36 is connected. The upper layer processing unit 35 performs protocol processing of the transport layer and above, and the application processing unit 36 executes application processing operating on the home agent.
In this configuration example, as will be described later, it is possible to store IP packets in the upper layer or in units of application data.

FIG. 3 is a diagram showing a first configuration example of the mobile station device 50. The communication interface unit 51 performs wireless or wired communication processing for the second layer and below, and corresponds to a connection interface with the outside. The received IP packet is transferred to the IP processing unit 52, where it is processed in accordance with Internet protocol regulations. Furthermore, when the received packet includes a telegram relating to mobile IP, it is transferred or notified to the mobile IP processing unit 53, and processing is performed based on the regulations of Mobile IP, which is one of mobile IP systems, for example. When the received packet is an IP packet not related to the mobile IP, the upper layer processing unit 55 and the application processing unit 56 are processed in this order. The upper layer processing unit 55
For example, it processes protocols above the IP layer such as TCP, UDP, and HTTP. Application processing unit 56
Performs individual application processing that operates on a communication protocol such as a Web browser.

In the transmission from the mobile station device 50, the transmission data generated by the application processing unit 56 is transferred to the upper layer processing unit 55, the IP processing unit 52, and the communication interface unit 51 in this order to carry out the transmission processing. Further, when transmitting a message relating to the mobile IP, the IP packet generated by the mobile IP processing unit 53 is transferred in the order of the IP processing 52 and the communication interface unit 51, and the transmission processing is performed. Further, when transmitting an IP packet including a communication start / end message, the IP packet or message information generated by the control message processing unit 54 is transferred in the order of the IP processing unit 52 and the communication interface unit 51, and the transmission process is performed. carry out.

FIG. 4 is a diagram showing a second configuration example of the mobile station device 50.

The basic components and operations are the same as those described in FIG. The difference is that the connection interface unit 57 is used instead of the application processing unit 56.
In this configuration, the mobile station device 50 serves as a relay terminal and connects a terminal device via a wireless or wired interface, and is provided with a connection interface that performs protocol processing of the second layer and below. When the mobile station device 50 operates as a router, the IP processing unit 52
And the connection interface unit 57 are connected to operate as a gateway, the upper layer processing unit 55 and the connection interface unit 57 are connected.

Also in this configuration, the mobile station device 50 can have the application processing unit 56 shown in the first configuration example. In that case, the application processing unit 56 is connected by connecting to the upper layer processing unit 55. Can be placed. When the mobile station device 50 operates only as a router, the upper layer processing unit 55 can be omitted.

Next, each operation of the home agent device 30 and the mobile station device 50 will be described below.

A format example of the communication disable period start / end telegram used in the following explanation of operation is shown in FIGS.
2 shows.

FIG. 7 is a flowchart showing the operation of the part of the home agent device 30 relating to the present invention.

When the home agent device 30 receives the IP packet, the home agent device 30 checks whether or not the IP packet is addressed to the mobile station device 50 accommodated (S131). The inspection of the IP packet is performed by referring to the destination address of the IP packet or the routing option header specified in the IP protocol as the option header. The routing option header is defined by the format shown in FIG. 24, and the home address field (H
By evaluating the ome Address (128) 245, it is possible to determine whether the IP packet is addressed to the mobile station device 50. If the IP packet is not addressed to the mobile station device 50, it is checked whether it is the IP packet from the mobile station device 50 (S135).

When the IP packet is from the mobile station device 50 and includes the communication unavailable period start message or the communication unavailable period end message (S136), the accommodated mobile station state managed by the home agent device 30. (For example, the binding cache in Mobile IP) is updated (S137), and then the IP packet is transferred to the normal reception process (S138). For example, when the communication-disabled period start message is detected, the mobile station device state is set to the communication disabled state, and subsequent packet transfer to the mobile station device 50 is not performed, but is stored in the storage unit 37 in the home agent device 30. Keep it.

When the telecommunicable period end message is detected,
The mobile station device state is set to the communicable state, and the transfer of the IP packet addressed to the mobile station device 50, which has been stored in the storage unit 37 in the home agent device 30 up to that point, is started to the mobile station device 50, and thereafter the proxy is performed. Mobile station device 5 for receiving
The transfer of the IP packet addressed to 0 to the mobile station device 50 is restarted. In order to carry out the above using the binding cache, it is necessary to newly provide a communication state flag so as to be able to indicate either the communication disabled state or the communication possible state.

If the IP packet is from the mobile station device 50 but does not include the start / end telegram of the incommunicable period, or if the IP packet is from a device other than the mobile station device 50, a normal reception process (S138) is performed. )I do.

IP packet addressed to mobile station device 50 (substitute)
When it is received (S131), the current mobile station device state is referred to (S132), and when it is in the incommunicable state (that is, during the incommunicable period), the received packet is accumulated and stored in the accumulation unit 37 (S133). , If the communication is possible (that is, outside the communication disabled period), normal mobile IP processing (S1
34) is carried out.

Here, when the mobile station device 50 stores IP packets in the incommunicable state, an upper layer protocol (for example, UDP, TCP, HTTP, etc.) for the IP layer or an application operation is performed to arrange data units. May be stored and stored in step (1), and when the home agent has a TCP gateway function, an ACK for the stored TCP segment may be transmitted as a proxy.

The normal receiving process (S138) is
This refers to processing defined by the Internet protocol, for example, routing processing and transfer of payload to an upper layer.

The normal mobile IP process (S134) is a process defined by Mobile IP or the like, for example, a binding update message process or transfer of a proxy reception packet.

FIG. 8 is a flowchart showing the operation of the part of the mobile station device 50 relating to the present invention.

When the mobile station device 50 detects the start of the handover process (S151), it transmits a communication deadline start message to the home agent device 30 (S152). Although it is not the start of handover, if the handover process has already started (during the handover period) and the end of the handover process is detected (S
153), and transmits a telecommunicable period end message to the home agent device 30. At this time, the incommunicable period end message may be explicitly transmitted to the CN that has previously transmitted the incommunicable period start message (S154). When an IP packet is received during the handover period (S15)
In step 5), normal reception processing is performed (S156). Here, the normal reception process (S156) refers to a process defined by the Internet protocol, for example, a routing process or a transfer of a payload to an upper layer.

Software for achieving packet loss reduction during the operation program update period executed by the mobile station device 50 by replacing "handover" in FIG. 8 with "operation program update" for operation. Wear wireless terminal can be realized. A specific example of the mobile communication method in the mobile communication system including at least the home agent apparatus 30 and the mobile station apparatus 50 according to the present invention will be described with reference to FIGS. 15 to 18.

Common components of FIGS. 15 to 18 will be described below. Home agent device (HA) 30 and correspondent node (Correspondent Node: hereinafter referred to as CN) 40
Are directly or indirectly connected to the Internet 1, and further different networks A10 and B
20 are connected to the Internet 1 via routers A11 and B21, respectively. The base station apparatus A12 exists in the network A10 and forms the wireless zone 13. A base station device B22 exists in the network B20 and forms a wireless zone 23. The wireless zones 13 and 23 are arranged at a distance.

First, in FIG. 15, the mobile station device 50 exists in the radio zone 13 and is accommodated in the base station device A12. In this state, the CoA belonging to the wireless zone 13 is registered in the home agent apparatus 30 accommodating the mobile station apparatus 50, and the home agent apparatus 3
The mobile station state managed by 0 is a communicable state.

In FIG. 16, when the mobile station device 50 tries to leave the wireless zone 13, that is, when a handover is started, the mobile station device 50 transmits a communication dead period start message to the home agent device 30. . The home agent apparatus 30 updates the mobile station state to a communication disabled state, and thereafter does not transfer to the mobile station apparatus 50 the mobile station apparatus 50 the IP packet addressed to the mobile station, which the home agent apparatus 30 receives by proxy. The data is stored and stored in the storage unit 37.

In FIG. 17, when the mobile station device 50 leaves the wireless zone 13 and does not belong to any of the wireless zones, the home agent device 30 continues to accumulate IP packets addressed to the mobile station device 50. In this state, the I transmitted to the CoA of the mobile station device 50 is transmitted.
Although the P packet reaches the network A10, the mobile station device 50 is already absent and cannot transfer the IP packet (from the router A11 of the network A10, I
CMP unreachable error is returned to the source node).

In FIG. 18, when the mobile station device 50 enters the wireless zone 23 and a wireless link is established, the mobile station device 50 transmits a communication dead period end message to the home agent device 30. Home agent device 3
0 updates the mobile station state to the communicable state and transfers the accumulated IP packet addressed to the mobile station apparatus to the mobile station apparatus 50.
Note that the home agent apparatus 30 needs to acquire a new CoA (which belongs to the network B20) of the mobile station apparatus 50 and update the binding prior to packet transfer, and for this reason, the mobile station apparatus 50 transmits. The binding update message may be used, or the new CoA of the mobile station device 50 belonging to the network B20 included in the incommunicable period end message may be used.

Although the mobile communication method described above relates to the handover accompanying the movement of the mobile station device 50, it can be applied to the case of updating the operation program. That is, when switching to a different wireless medium in the state of FIG. 15, since the access network is changed, it can be treated equivalently as moving to a different network as shown in FIG. Therefore, when it is decided to update the operation program while existing in the wireless zone 13, the mobile station device 50 transmits a communication dead period start message to the home agent device 30. After the operation program is updated, that is, when the mobile station device 50 moves to the wireless zone 23 under the logically different network and a wireless link is established, the mobile station device 50 transmits a non-communicable period end message to the home agent device 30, and the home agent The IP packet transferred from the device 30 is received.

In the above description, the home agent device 30 in Mobile IP as an example of the mobile IP receives the IP packet addressed to the mobile station device as a proxy, temporarily stores it, and transfers it after the mobile station returns. In addition to the device 30, a device that performs the same function may be provided, or storage may be performed by a device other than the home agent device 30. In that case, the storage unit 37 included in the home agent device 30 is used as the home agent. It can be realized by moving from the device 30 to another device.

As described above, according to the embodiment of the present invention, the home agent receives the IP packet addressed to the mobile station, which should be originally received by the mobile station during the communication incompatibility period caused by the handover or the operation program update, by the home agent. It is possible to reduce the packet loss by transferring the stored packets when the mobile station becomes available for communication, and further reduce the mobile station communication load thereafter, thus providing an efficient mobile communication system. Can be realized.

Further, when the switching to a different communication medium occurs due to the update of the operation program, smooth roaming can be realized without packet transfer between different carriers having a security problem.

(Second Embodiment) A second embodiment of the present invention will be described with reference to FIGS. 1 to 5, 7, 9, 10, 15 to 22.

The basic structure and operation of this embodiment are the same as those of the first embodiment, and only the points different from the first embodiment will be described below.

The present embodiment differs from the first embodiment in that a correspondent node (Correspondent Node:
(CN) is introduced, and the mobile station transmits the communication start / end telegram to the communication partner.

FIG. 20 is a diagram showing a configuration example of a mobile communication system in the second embodiment according to the present invention, which is different from FIG. 19 showing a configuration example of the mobile communication system in the first embodiment. The communication partner (C
N) 60 is a point directly or indirectly connected to the network 1.

FIG. 5 is a diagram showing a configuration example of the communication device 60 which is a communication partner (CN). In FIG. 5, the communication device 60 is directly or indirectly connected to the network 1, and specifically, the communication interface unit 61 executes the connection processing of the second layer and below. The IP packet received by the communication interface unit 61 is transferred to the IP processing unit 62, where it is processed in accordance with the Internet protocol regulations. When the received packet includes a message relating to the mobile IP, it is transferred or notified to the mobile IP processing unit 63, and for example, Mobile I which is one of the mobile IP methods.
The process based on the rule of P is performed.

Further, when the communication-disabled period start message or the communication-disabled period end message is received from the mobile station device 50, it is transferred or notified to the control message processing unit 64,
The process according to the procedure described later is performed. When the communication device 60 transmits a telegram relating to mobile IP, the telegram generated by the mobile IP processing unit 63 is transferred to the IP processing unit 62 and the communication interface unit 61 in this order to perform the transmission process.

Each operation of the communication device 60 and the mobile station device 50 will be described with reference to FIGS. 21 and 22 show format examples of the communication disabled period start / end telegrams used in the description of the operation.

FIG. 9 is a flowchart showing the operation of the part of the mobile station device 50 relating to the present invention. The difference from the first embodiment is that in processes S157 and S158, the communication unavailable period start / end telegram is transmitted not only to the home agent device 30 but also to the communication device 60 that is a communication partner.

FIG. 10 is a flowchart showing the operation of the part of the communication device (CN) 60 relating to the present invention.

When the communication device 60 receives the IP packet, the communication device 60 determines whether the IP packet is from the mobile station device 50 by referring to the binding cache or the like (S161). If the packet is an IP packet from the mobile station device 50 and includes a communication deadline start message (S16).
2) Update the entry corresponding to the mobile station device 50 in the binding cache (S163).

For example, the communication device 60 deletes the entry corresponding to the mobile station device 50 in the binding cache so that when the IP packet addressed to the mobile station device 50 is subsequently transmitted, the communication device 60 uses the home address of the mobile station device 50. Carry out the operation of sending. At this time, the binding cache is referred to, but since the entry corresponding to the mobile station device 50 has already been deleted, it is not transmitted to the CoA used by the mobile station device 50 in the past. Further, the communication device 60 deletes the CoA of the entry corresponding to the mobile station device 50 in the binding cache, or / and further changes the mobile station state to the incommunicable state, and the destination of the IP packet addressed to the mobile station device 50 to be transmitted thereafter. Is set to the home address of the mobile station device 50. At this time, the IP packet addressed to the mobile station device 50 during the incommunicable period, which the home agent device 30 has received by proxy, is accumulated in the home agent device 30 according to the procedure described in the first embodiment, and will be described later. It is possible to transfer the data when the mobile station device 50 ends the incommunicable period.

When the IP packet received by the communication device 60 is from the mobile station device 50 and includes a communication deadline end message (S164), the binding cache updated when the communication deadline start message is received is moved. The entry corresponding to the station device 50 is updated again (S16).
5). For example, when the entry is deleted first, the home address and CoA described in the communication end-of-communications message
Register the entry using.

Alternatively, the CoA of the entry is overwritten with the CoA described in the communication end period message. Process S1
By performing step 65, subsequent IP packets addressed to the mobile station device are transmitted to the new CoA.

It is determined that the mobile station device 50 does not need to send the communication start / end telegram to all the communication devices 60, and that it is necessary to notify the communication device 60 that it is currently communicating or is in the communication incapable period. A message may be transmitted to the communication device 60 that has performed the communication.

As described above, according to the embodiment of the present invention, the IP packet addressed to the mobile station device 50 that should be originally received by the mobile station device 50 during the communication incommunicable period due to the handover or the update of the operation program is sent to the home agent. Device 30
Is received by proxy and stored, and the stored IP packet is transferred when the mobile station device 50 becomes communicable to reduce packet loss and further reduce the communication load of the mobile station device 50 thereafter. Therefore, an efficient mobile communication system can be realized.

Furthermore, when switching to a different communication medium occurs due to the update of the operation program, smooth roaming can be realized without packet transfer between different carriers having a security problem.

Further, when the mobile station device 50 is in the incommunicable period, the communication device 60 (C
By transmitting to the home address of the mobile station apparatus 50 at the time of N), packet loss in the base station apparatus can be avoided.

(Third Embodiment) FIGS. 3, 4, 6, 11, 12, 15 to 22, regarding a third embodiment of the present invention.
25 will be described.

The basic structure and operation of the third embodiment of the present invention are the same as those of the first and second embodiments, and are different from the first and second embodiments below. Will be described only.

The present embodiment is different from the first and second embodiments in that the mobile station device transmits a start / end message of incommunicable period to the base station device, and the base station device sends The point is to receive and process the transmitted communication start / end telegram.

FIG. 6 is a diagram showing a configuration example of the base station device 70. In FIG. 6, the base station device 70 is directly or indirectly connected to the network 1. Specifically, the communication interface unit 75 on the wired line side performs the connection process of the second layer and below. The IP packet received by the communication interface unit 75 is transferred to the IP processing unit 72, where it is processed according to the Internet protocol regulations. In case of packet transfer to mobile station device,
The IP processing unit 72 transfers the IP packet to the communication interface unit 71 and transmits the IP packet to the wireless line side.
The IP packet received from the wireless line via the communication interface unit 71 is transferred to the wired line from the communication interface unit 75 via the IP processing unit 72.

The base station device 70 according to the present embodiment is
When the mobile station device 50 manages the communicable state according to the procedure described later and the mobile station device 50 that is the packet transfer destination is incommunicable, the IP packet is transferred from the IP processing unit 72 to the mobile IP proxy processing unit 73. After being processed according to the procedure described later, it is sent out via the IP processing unit 72 and the communication interface unit 75.

Communication start / end messages for updating the communication-enabled state of the mobile station device 50 are the communication interface unit 7.
1. Transferred or notified to the control message processing unit 74 via the IP processing unit 72, and processed according to the procedure described later.

Each operation of the base station apparatus 70 and the mobile station apparatus 50 will be described with reference to FIGS. In addition,
21 and 22 show examples of the format of the communication start / end telegram used in the operation description.

FIG. 11 is a flowchart showing the operation of the part of the mobile station device 50 relating to the present invention. The difference from the first and second embodiments is that processes S157 and S15.
In No. 8, the communication start / end telegram is transmitted not only to the home agent device 30 (and the communication partner 60 as necessary) but also to the base station device 70.

FIG. 12 is a flowchart showing the operation of the part of the base station device 70 relating to the present invention. Base station device 7
0 receives the IP packet, the I addressed to the mobile station device 50
It is confirmed whether it is a P packet (S171). When the packet is received from the mobile station device 50 (S175) and the communication disable period start / end telegram is included (S17).
6) The mobile station status is updated (177). The mobile station state is managed by the mobile station state management table 160 shown in FIG. 25, and the home address of the mobile station device 50 and Co
A, it has at least a flag indicating whether or not it is currently in the incommunicable period, and is updated based on the information described in the electronic message from the mobile station device 50. For example, in the mobile station state management table 160 shown in FIG. 25, the home address HoA1
The mobile station device having the present value currently has CoA1 as the CoA, indicating that it is in the communication incapable period. The mobile station device having the home address HoA2 currently has CoA2 as CoA, which indicates that it is not in the incommunicable period.

When the received packet is an IP packet addressed to the mobile station device 50 (S171), it is confirmed from the mobile station state management table whether the mobile station device 50 is in the incommunicable period (S172). If the communication is possible (not in the non-communication period), the data is transferred according to the normal transfer process (S17).
4) During the communication incapable period, the header of the received packet is manipulated (the packet destination address is changed to the home address of the mobile station device 50) (S173), and the retransmission is sent out by the home agent by the proxy reception. Storage transfer is performed according to the procedure described in the embodiment.

When the procedure specified by Mobile IP is followed, the base station device 70 can achieve a desired operation by processing the routing option header of the received packet in place of the mobile station device 50. That is, the next (last) hop address (home address) and I described in the routing option header
The destination address of the P header is exchanged, and the number of remaining segments of the routing option header is set to "0".

The base station device 70 sends the IP packet whose header is manipulated in the process 173 to the home agent device 3
When 0 is received, it is possible to determine whether this IP packet is rerouted to the home address by the operation of the base station device by checking the routing option header.

Therefore, in the mobile communication system according to the present invention, when the mobile station device 50 does not send the incommunicable period start message to the home agent device 30, or the home agent device 30 cannot receive the incommunicable period start message. However, the home agent device 30
Can estimate that the mobile station device 50 has entered the incommunicable period.
A desired function can be achieved by accumulating IP packets addressed to 0 and transferring the accumulated IP packets at the time when the communication-disabled period end message is received from the mobile station device 50.

As described above, according to the embodiment of the present invention, the home agent apparatus receives the IP packet addressed to the mobile station apparatus which is supposed to be received by the mobile station apparatus during the incommunicable period due to the handover or the update of the operation program. It is possible to reduce the packet loss by transferring the accumulated IP packet when the mobile station device becomes communicable while receiving the proxy and storing the packet, and further reduce the communication load of the mobile station device thereafter. It is possible to realize an efficient mobile communication system.

Furthermore, when a change to a different communication medium occurs due to the update of the operation program, smooth roaming can be realized without packet transfer between different carriers having a security problem.

Furthermore, the mobile station apparatus notifies the base station apparatus in communication of the start and end of the incommunicable period, so that packet loss in the base station apparatus can be avoided.

(Embodiment 4) A fourth embodiment of the present invention will be described with reference to FIGS. 3, 4, 6 and 11 to 23.

The basic structure and operation of this embodiment are the same as those of the first to third embodiments.
Only the points different from the first to third embodiments will be described below.

The present embodiment is different from the first to third embodiments in that an IP packet transfer request is issued to the base station device 70 at an arbitrary time before the mobile station 50 enters the incommunicable period. It is the point to send.

Each operation of mobile station apparatus 50 and base station apparatus 70 will be described below with reference to FIGS. A format example of the transfer request message used in the operation description is shown in FIG. In FIG. 23, a code field (code: 1 byte) describes an identification number indicating the transfer request message 143.

FIG. 13 is a flowchart showing the operation of the part of the mobile station device 50 relating to the present invention. The difference from the first to third embodiments is that the mobile station device 50 is connected to the base station device 70. This is the point that describes the operation at the time.
That is, when the mobile station device 50 is connected to the new base station device 70 (S159), the transfer request message 143 is transmitted to the base station device 70. It is also possible to operate the mobile station apparatus 50 by combining the operation shown in FIG. 13 and the operation shown in any of FIGS.

FIG. 14 is a flowchart showing the operation of the part of the base station device 70 relating to the present invention.

Upon receiving the IP packet, the base station device 70 confirms whether the IP packet is addressed to the mobile station device 50 (S171). When the IP packet is received from the mobile station device 50 (S175) and the transfer request message is included (S191), the mobile station state is updated (S192).
The mobile station status is managed by the mobile station status management table, and has at least the home address and CoA of the mobile station apparatus 50 and a flag indicating the presence / absence of a transfer request.
Will be updated based on the information described in the transfer request message from.

When the received packet is an IP packet addressed to the mobile station device 50 (S171), it is confirmed from the mobile station state management table whether communication with the mobile station device 50 is impossible and the transfer flag is ON (S190). ), Mobile station device 50
When communication is possible or impossible but the transfer flag is OFF, transfer is performed according to normal transfer processing (or after discarding, an ICMP unreachable message is sent to the packet transmission source) (S174), communication is not possible and the transfer flag is ON. If there is, operate the header of the received packet (change the packet destination address to the home address of the mobile station device 50)
(S173), the home agent device 30 performs proxy reception by retransmitting, and stores and transfers according to the procedure described in the above embodiment.

When the procedure specified by Mobile IP is followed, the base station device 70 can achieve the desired operation by processing the routing option header of the received packet in place of the mobile station device 50. That is, the next (last) hop address (home address) and I described in the routing option header
The destination address of the P header is exchanged, and the number of remaining segments of the routing option header is set to "0".

When the home agent device 30 receives the IP packet whose header has been manipulated by the base station device 70 in step S173, the routing option header is confirmed, so that this IP packet is transmitted to the base station device 7
It is possible to determine whether or not the home address is re-routed by the operation of 0.

Therefore, in the mobile communication system according to the present invention, when the mobile station device 50 does not send the incommunicable period start message to the home agent device 30, or the home agent device 30 cannot receive the incommunicable period start message. However, the home agent device 30
Can estimate that the mobile station device 50 has entered the incommunicable period.
A desired function can be achieved by accumulating IP packets addressed to 0 and transferring the accumulated IP packets at the time when the communication-disabled period end message is received from the mobile station device 50.

As described above, according to the embodiment of the present invention, the home agent apparatus sends an IP packet destined for the mobile station apparatus, which should be originally received by the mobile station apparatus during the incommunicable period due to the handover or the update of the operation program. It is possible to reduce the packet loss by transferring the accumulated IP packet when the mobile station device becomes communicable while receiving the proxy and storing the packet, and further reduce the communication load of the mobile station device thereafter. It is possible to realize an efficient mobile communication system.

Furthermore, when switching to a different communication medium occurs due to the operation program update, smooth roaming can be realized without packet transfer between different carriers which has a security problem.

Furthermore, the mobile station device notifies the base station device of the transfer request at the time of connection with the base station device, so that it is possible to avoid packet loss due to unexpected handover or communication interruption.

[0125]

According to the mobile communication method of the present invention, the home agent proxy-receives the IP packet addressed to the mobile station apparatus which should be originally received by the mobile station apparatus during the communication disabled period due to the handover or the update of the operation program. And the mobile station device becomes ready to receive
By transferring P packets, it is possible to reduce packet loss and further reduce the communication load on the mobile station device thereafter, and it is possible to realize an efficient mobile communication system.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a first configuration of a home agent device according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a second configuration of the home agent device according to the embodiment of the present invention.

FIG. 3 is a conceptual diagram showing a first configuration of a mobile station apparatus according to an embodiment of the present invention.

FIG. 4 is a conceptual diagram showing a second configuration of a mobile station device according to an embodiment of the present invention.

FIG. 5 is a conceptual diagram showing a configuration of a communication device (CN) according to an embodiment of the present invention.

FIG. 6 is a conceptual diagram showing a configuration of a base station device according to an embodiment of the present invention.

FIG. 7 is a flowchart showing a processing procedure of the home agent device according to the embodiment of the present invention.

FIG. 8 is a flowchart showing a first processing procedure of the mobile station apparatus according to the embodiment of the present invention.

FIG. 9 is a flowchart showing a second processing procedure of the mobile station apparatus according to the embodiment of the present invention.

FIG. 10 is a communication device (CN) according to an embodiment of the present invention.
Flowchart showing the processing procedure

FIG. 11 is a flowchart showing a third processing procedure of the mobile station apparatus according to the embodiment of the present invention.

FIG. 12 is a flowchart showing a first processing procedure of the base station device according to the embodiment of the present invention.

FIG. 13 is a flowchart showing a fourth processing procedure of the mobile station apparatus according to the embodiment of the present invention.

FIG. 14 is a flowchart showing a second processing procedure of the base station device according to the embodiment of the present invention.

FIG. 15 is a first conceptual diagram for explaining the operation of the mobile communication system according to the embodiment of the present invention.

FIG. 16 is a second conceptual diagram for explaining the operation of the mobile communication system according to the embodiment of the present invention.

FIG. 17 is a third conceptual diagram for explaining the operation of the mobile communication system according to the embodiment of the present invention.

FIG. 18 is a fourth conceptual diagram for explaining the operation of the mobile communication system according to the embodiment of the present invention.

FIG. 19 is a conceptual diagram showing a first configuration of a mobile communication system according to an embodiment of the present invention.

FIG. 20 is a conceptual diagram showing a second configuration of the mobile communication system according to the embodiment of the present invention.

FIG. 21 is a conceptual diagram showing an example of a communication impossible period start message format according to the embodiment of the present invention.

FIG. 22 is a conceptual diagram showing an example of an incommunicable period end message format according to an embodiment of the present invention.

FIG. 23 is a conceptual diagram showing a transfer request message format example according to the embodiment of the present invention.

FIG. 24 is a schematic diagram showing a configuration of a routing option header according to an embodiment of the present invention.

FIG. 25 is a schematic diagram showing an example of a mobile station state management table managed by a base station apparatus according to an embodiment of the present invention.

[Explanation of symbols]

1 Internet (network) 10 First Network 11 First Router 12 First base station 13 First wireless area 20 Second network 21 Second Router 22 Second base station 23 Second wireless area 30 Home Agent Device 31 Communication interface section 32 IP processing unit 33 Mobile IP processing unit 34 Control message processing unit 35 Upper layer processing unit 36 Application Processing Unit 37 Storage 39 Control unit 40, 60 CN (Correspondent Node) 50 mobile station equipment 51 Communication interface section 52 IP processing unit 53 Mobile IP processing unit 54 Control message processing unit 55 Upper layer processing unit 56 Application Processing Unit 57 Connection interface section 61 Communication interface section 62 IP processing unit 63 Mobile IP processing unit 64 Control message processor 65 Upper layer processing unit 66 Application Processing Unit 70 base station device 71 Communication interface section (wireless side) 72 IP processing unit 73 Mobile IP processing unit 74 Control message processor 75 Communication interface (wired side) 141 Communication unavailable period start message 142 Incompletion period end message 143 Transfer request message 150 Routing Option Header 160 Mobile station status management table

Claims (23)

[Claims] 1. In a communication method of a network using a mobile IP including at least a mobile station and a home agent, the mobile station becomes unable to communicate with the home agent at the time when it becomes clear that the mobile station is in the incommunicable period. The home agent, which has transmitted the start message and received the start message for the incommunicable period, accumulates IP packets addressed to the mobile station which will be subsequently received by proxy, and the mobile station sends the end message for the incommunicable period at the end of the incommunicable period. The home agent, which has transmitted the message to the agent and has received the message indicating the end of the incommunicable period, transfers the IP packet addressed to the mobile station, which has been transferred from the home agent.
A mobile communication method characterized by receiving and processing P packets. 2. The mobile communication method according to claim 1, wherein the home agent returns a response message in response to the incommunicable period start message. 3. The information relating to the estimated incommunicable time is included in the incommunicable period start telegram.
Or the mobile communication method according to 2. 4. The mobile station further transmits a communication-disabled period start message to a communication partner when it becomes clear that the communication-disabled period is reached, and the communication partner receives the communication-disabled period start message. Then, the mobile communication method according to any one of claims 1 to 3, wherein the IP packet addressed to the mobile station, which has entered the communication disabled period, is transmitted to the home address of the mobile station. 5. The mobile station further transmits a communication-disabled period start message to the base station when it becomes clear that a communication-disabled period is reached, and the base station enters the communication-disabled period. 5. The mobile communication method according to claim 1, wherein the addressed packet header is processed and transmitted. 6. The home agent sends an IP to a mobile station, which receives by proxy after receiving the incommunicable period start message.
The mobile communication method according to any one of claims 1 to 5, wherein protocol processing is performed so that packets can be accumulated in an upper layer or in units of application data. 7. The incommunicable period start message is transmitted to the home agent when it becomes clear that the incommunicable period is reached, and the incommunicable period end message is sent to the home agent when the incommunicable period ends. A mobile station device comprising: a means for transmitting the IP packet transferred from the home agent after the transmission of the incommunicable period end message, and a means for receiving the IP packet. 8. A means for receiving and processing a communication deadline start message from a mobile station, and an IP addressed to the mobile station that has entered the communication deadline.
A home agent comprising: means for accumulating packets after proxy reception; and means for transferring an IP packet addressed to the mobile station, which has been previously accumulated, to the mobile station when receiving an incommunicable period end message from the mobile station. apparatus. 9. A means for receiving a message for starting the communication-disabled period and performing a protocol process so that an IP packet addressed to a mobile station that has entered the communication-disabled period can be stored in an upper layer or in application data units after proxy reception. The home agent device according to claim 8, wherein 10. A mobile radio is a software defined radio device capable of dynamically updating its operation program, transmits a communication deadline start telegram to the home agent when updating the program, and can communicate after completion of the program update. 7. The incommunicable period end telegram is transmitted to the home agent when the state is reached.
The mobile communication method according to any one of 1. 11. A software defined radio device capable of dynamically updating an operation program, means for transmitting a communication deadline start message to a home agent device when updating the program, and a state in which communication is possible after the program update is completed. And a means for transmitting an incommunicable period end telegram to the home agent apparatus at the time of becoming a mobile station apparatus. 12. A mobile communication system comprising the home agent apparatus according to claim 8 or 9 and the mobile station apparatus according to claim 7 or 11. 13. The mobile station transmits an out-of-office transfer request message to the base station after communication with a new base station becomes possible, When communication with the mobile station is lost in the
11. The proxy reception of the packet, the processing of the header of the IP packet, and the transmission of the processed packet are transmitted.
The mobile communication method according to any one of 1. 14. The mobile station device according to claim 7, wherein an out-of-office transfer request message is transmitted to the base station after communication with a new base station becomes possible. 15. A means for receiving an unattended transfer request message from a mobile station, and a means for receiving an IP packet addressed to the mobile station by proxy when communication with the mobile station is lost thereafter.
A base station device, comprising means for processing a header of an IP packet received by proxy and transmitting the processed header. 16. A means for receiving and processing an incommunicable period start message from a mobile station, a proxy for receiving an IP packet addressed to a mobile station that has entered the incommunicable period, and a proxy-received IP.
A base station device, comprising: means for processing a packet header and transmitting the processed header. 17. A means for receiving an unattended transfer request message and an incommunicable period start message from a mobile station, and a means for receiving communication with the mobile station after receiving the unattended transfer request message,
Alternatively, when a communication-disabled period start message is received from the mobile station, a means for receiving an IP packet addressed to the mobile station by proxy,
A base station device, comprising means for processing a header of an IP packet received by proxy and transmitting the processed header. 18. A mobile device comprising the home agent apparatus according to claim 8 or 9, the mobile station apparatus according to any one of claims 14 to 16, and the base station apparatus according to any one of claims 15 to 17. Communications system. 19. The method according to claim 7, further comprising transmitting a communication-disabled period start message to a communication partner.
1. The mobile station device according to 1. 20. The mobile station apparatus according to claim 14, further comprising transmitting an incommunicable period start message to a communication partner. 21. Communication comprising means for receiving and processing a communication-disabled period start message, and means for transmitting an IP packet addressed to a mobile station that has entered the communication-disabled period to the home address of the mobile station. apparatus. 22. A mobile communication system comprising the home agent device according to claim 8 or 9, the mobile station device according to claim 19, and the communication device according to claim 21. 23. The home agent apparatus according to claim 8 or 9, the mobile station apparatus according to claim 20, the base station apparatus according to any one of claims 15 to 17, and claim 2.
A mobile communication system comprising the communication device according to 1.