JP5245752B2 - Access network gateway device - Google Patents

Description

  The present invention relates to an access network gateway device, and relates to an access network gateway device having a function of relocation processing for changing a communication path generated when a mobile device moves in a mobile WiMAX (Mobile Worldwide Interoperability for Microwave Access) network or the like. The present invention relates to a gateway device.

  Mobile WiMAX is an international standard for high-speed wireless LAN technology. As shown in FIG. 12, the network configuration includes an access service network (ASN) that is an access network and a core service network (IP core network). CSN).

In a mobile WiMAX network, an access network gateway device (ANS-GW) 12-1 is connected to a base station device (BS) 12-2 via an access service network (ASN), and a core service. -It is connected to the service provider apparatus 12-3, the authentication server (AAA server) 12-4, the home agent (Home Agent) 12-5, etc. via the network (CSN).

  The mobile station (subscriber terminal) 12-6 is connected to the base station apparatus (BS) 12-2 via a radio link, and the access network gateway apparatus (ANS-GW) 12-1 is connected to the base station apparatus (BS). 12-2 is controlled and the connection setting of the mobile radio communication with respect to the mobile device (subscriber terminal) 12-6 is managed.

When the mobile device (subscriber terminal) 12-6 moves as indicated by high-speed movement and moves to a wireless zone different from the wireless zone under the control of the currently communicating base station device (BS) 12-2 # 1, it is necessary to implement a base station apparatus that covers the radio zone (BS) 12-2 # relocation process for changing the communication route via 2.

  Relocation in the WiMAX network will be described with reference to FIG. Here, the R3 interface, the R4 interface, and the R6 interface will be described. Hereinafter, the access network gateway device (ANS-GW) is referred to as a gateway device (ANS-GW).

  For example, the interface between the service provider device 12-3 and the gateway device (ANS-GW) 12-1 connected via the core service network (CSN) is the R3 interface, and the gateway device (ANS-GW). The interface between 12-1 is called R4 interface, and the interface between the gateway device (ANS-GW) 12-1 and the base station device (BS) 12-2 is called R6 interface. These interfaces are defined by the WiMAX forum NWG-Stage 2 and standardized as WiMAX standard technology.

  Now, it is assumed that the mobile device (subscriber terminal) 12-6 under the base station device 12-2 # 1 starts communication with the service provider device 12-3 via the gateway device 12-1 # 1. . The communication path at this time is (1)-(2). When the mobile device (subscriber terminal) 12-6 subordinate to the base station device 12-2 # 1 moves to the subordinate of the base station device 12-2 # 2, communication of the mobile device (subscriber terminal) 12-6 is performed. The base station apparatus 12-2 # 1 is handed over to the base station apparatus 12-2 # 2. The communication path at this time is (1)-(3)-(5), and the mobile device (subscriber terminal) 12-6 uses this communication path (1)-(3)-(5) Communication with the provider device 12-3 is continued.

  In this state, data between the mobile device (subscriber terminal) 12-6 and the service provider device 12-3 is transmitted / received via the gateway device 12-1 # 1 and the gateway device 12-1 # 2. Redundancy is included in the communication path. In this case, the communication route that optimally uses the network is route (4)-(5), and it is preferable to switch from route (1)-(3)-(5) to route (4)-(5). .

  This switching can be performed by manual switching by a maintenance person or automatic switching in the gateway device (ANS-GW) 12-1. However, the trigger for switching is not defined in WiMAX. That is, the temporary route (1)-(3)-(5) including the route (1) of the R3 interface between the gateway device (ANS-GW) 12-1 and the service provider device 12-3 is changed to the gateway. Regarding the R3 relocation to switch to the final route (4)-(5) not including the route (3) between the devices (ANS-GW) 12-1, the WiMAX standard specification defines the signal interface at the time of R3 relocation. However, there is no provision for the trigger of the R3 relocation process.

R3 relocation is described in paragraphs 0007 to 0018 of Patent Document 1 below. Further, in Patent Document 1, as triggers for R3 relocation, (a) system congestion, (b) resource shortage (overconnection count over), (c) bandwidth over (R3 side use over bandwidth), (d) R3 by maintenance command The activation / non-activation of the relocation process is described.
JP 2008-141374 A

  The trigger for the conventional R3 relocation described in the above-mentioned Patent Document 1 is a trigger focusing on factors such as system resources in the switching source gateway device (ANS-GW # 1). An object of the present invention is to increase the success rate of R3 relocation by performing the R3 relocation process in response to a factor of the gateway device (ANS-GW # 2) as a switching destination. Furthermore, the operation policy that has not been defined in the past and various triggers for the R3 relocation process due to a system failure are clarified.

The access network gateway device of the present invention connects the core service network and the access service network, and performs the first communication via another access network gateway device associated with the hand-over of the mobile device. An access network gateway apparatus having a relocation processing function for changing a path to a second communication path that does not pass through another access network gateway apparatus , wherein the path is located only through the second communication path. Time measuring means for measuring an elapsed time from the start of communication through the first communication path in the corresponding access network gateway apparatus, and the elapsed time measured by the time measuring means is a predetermined standby time. Determining means for determining whether or not the value has been exceeded; The elapsed time to the judgment exceeds a waiting time that the predefined, and a starting means for starting the relocation process by.

  A storage means for monitoring the number of simultaneous connections with the core service network in the access network gateway device that passes only through the second communication path, and storing the value of the number of simultaneous connections in a memory; A determination unit that compares a preset reference value with the value of the number of simultaneous connections and determines whether the value of the number of simultaneous connections is smaller than the preset reference value; and the number of simultaneous connections by the determination unit And an activation means for activating the relocation process when it is determined that the value is smaller than the preset reference value.

  In addition, the access network gateway device that passes only through the second communication path monitors the number of simultaneous connections with the other access network gateway devices, and stores the value of the number of simultaneous connections in a memory. Storing means for comparing, determining means for comparing the preset reference value with the value of the number of simultaneous connections, and determining whether the value of the number of simultaneous connections is greater than the preset reference value, and the judging means And starting means for starting the relocation processing when it is determined that the value of the number of simultaneous connections is larger than the preset reference value.

  Further, in the access network gateway device that passes only through the second communication path, a time measuring unit that measures an elapsed time from the start of communication through the first communication path, and the elapsed time are defined in advance. A determination unit that determines whether or not a standby time has been exceeded; and an activation unit that starts the relocation processing when the determination unit determines that the elapsed time has exceeded the predetermined standby time. It is.

  Further, in the access network gateway device that passes only through the second communication path, the memory usage rate or the CPU usage rate of its own device is measured, the storage means for storing the actual measurement result, a preset reference value, A determination unit that compares the memory usage rate or the CPU usage rate and determines whether the value of the memory usage rate or the CPU usage rate is smaller than the preset reference value; and the memory usage rate by the determination unit Or it is provided with the starting means which starts the said relocation process, when it determines with the value of CPU usage rate being smaller than the said reference value set beforehand.

  The success rate of R3 relocation can be increased by performing the R3 relocation process at an opportunity that focuses on the factor of the gateway device (ANS-GW # 2) that is the switching destination. That is, in the R3 relocation based on the factor of the switching source gateway device (ANS-GW # 1), the R3 relocation is performed without reflecting the state of the switching destination gateway device (ANS-GW # 2). It can be unsuccessful. On the other hand, the success rate of R3 relocation can be increased by performing R3 relocation based on the state of the gateway device (ANS-GW # 2) of the switching destination.

In Figure 1, the mobile station moves as shown by (subscriber terminal) 12-6 arrow under the base station apparatus 12 2 # 2 from under the base station apparatus 12 2 # 1, the communication path (1) - (2) communication path from (1) - (3) - (5) if continued communication, the gateway device (ANS-GW) 12-1 at # 2, the amount of processing a threshold set pre Me data but when the drops below, to execute the R3 relocation process.

  In the gateway device (ANS-GW) 12-1 # 2, a processing data amount reference value AAA, which is a threshold for starting the R3 relocation processing, and a unit time CCC for measuring the processing data amount are set in the memory in advance. Then, the gateway device (ANS-GW) 12-1 # 2 measures the total amount of processing data in its own device for the unit time CCC and stores it in the memory as the processing data amount BBB per unit time.

  The gateway device (ANS-GW) 12-1 # 2 periodically compares the processing data amount reference value AAA with the processing data amount BBB per unit time, and the processing data amount BBB per unit time is the processing data amount reference. If the value is smaller than the value AAA, R3 relocation processing is executed, and the route (1)-(3)-(5) is changed to the route (4)-(5).

  A second embodiment is shown in FIG. In the figure, it is assumed that the mobile device (subscriber terminal) 12-6 that has moved communicates along the route (1)-(3)-(5). In the gateway device (ANS-GW) 12-1 # 2, the reference value FFF of the simultaneous connection number of the R3 interface of the route (4) is set in the memory in advance. The gateway device (ANS-GW) 12-1 # 2 monitors the number of simultaneous connections of the route (4). When the number of simultaneous connections is smaller than the simultaneous connection number reference value FFF, the R3 relocation process is executed. Route (1)-(3)-(5) is changed to route (4)-(5).

  A third embodiment is shown in FIG. In the figure, it is assumed that the mobile device (subscriber terminal) 12-6 that has moved communicates along the route (1)-(3)-(5). The gateway device (ANS-GW) 12-1 # 2 executes the R3 relocation process when the data amount of the route (3) exceeds a preset data amount.

  In the gateway device (ANS-GW) 12-1 # 2, the processing data amount reference value DDD for starting the R3 relocation processing and the unit time CCC for measuring the processing data amount flowing through the route (3) are stored in the memory in advance. Set. The gateway device (ANS-GW) 12-1 # 2 measures the processing data amount of the path (3) of the unit time CCC and stores it in the memory as the processing data amount BBB per unit time.

  The gateway device (ANS-GW) 12-1 # 2 periodically compares the processing data amount reference value DDD for starting the R3 relocation processing with the processing data amount BBB per unit time, and processes the data per unit time. If the amount BBB is larger than the processing data amount reference value DDD, R3 relocation processing is executed, and the route (1)-(3)-(5) is changed to the route (4)-(5).

  The difference from the first embodiment will be described. The third embodiment pays attention to the data amount of the route (3), and the first embodiment is a gateway device (ANS-GW) 12-1. It pays attention to the total data volume of # 2. After the moved mobile device (subscriber terminal) 12-6 starts communication on the route (1)-(3)-(5), the processing data amount of the route (3) is the gateway device (ANS-GW) 12 When the processing data amount reference value set in -1 # 2 is exceeded, R3 relocation processing is executed.

FIG. 4 is an explanatory diagram of the fourth embodiment, in which the mobile device (subscriber terminal) 12-6 is connected to the base station device # 2 (subordinate station) from the base station device # 1 (BS) 12-2 # 1. BS) 12-2 # moves under the 2, route (1) - (3) - (from the time of starting the communication by 5), the gateway device # 2 (ANS-GW # 2 ) 12-1 # 2 and starts measuring the elapsed time in, if it is determined that has elapsed variably relocation latency EEE as defined previously, the gateway device # 2 (ANS-GW # 2 ) 12-1 # 2 executes the R3 relocation process Then, the communication path (1)-(3)-(5) is changed to the communication path (4)-(5).

  A fifth embodiment is shown in FIG. In the figure, it is assumed that the mobile device (subscriber terminal) 12-6 that has moved communicates with the route (1)-(3)-(5). In the gateway device (ANS-GW) 12-1 # 2, the memory usage threshold or CPU usage threshold that triggers the R3 relocation processing is stored in advance in the memory as the memory usage threshold HHH or CPU usage threshold III, respectively. Set it.

  The gateway device (ANS-GW) 12-1 # 2 measures the memory usage rate or CPU usage rate of its own device, and the measurement result is stored in the memory as the memory usage rate JJJ per unit time or the CPU usage rate KKK per unit time. Store. The gateway device (ANS-GW) 12-1 # 2 periodically compares the memory usage rate JJ per unit time with the memory usage rate threshold HHH, and the memory usage rate JJJ per unit time is smaller than the memory usage rate threshold HHH. If it is a value, the gateway device (ANS-GW) 12-1 # 2 executes the R3 relocation process and changes the route (1)-(3)-(5) to the route (4)-(5). .

  Further, the gateway device (ANS-GW) 12-1 # 2 periodically compares the CPU usage rate KKK per unit time with the CPU usage rate threshold III, and the CPU usage rate KKK per unit time is determined as the CPU usage rate threshold III. If the value is smaller, the gateway device (ANS-GW) 12-1 # 2 executes R3 relocation processing, and routes (1)-(3)-(5) are changed to routes (4)-(5). change.

  A sixth embodiment is shown in FIG. After the moved mobile device (subscriber terminal) 12-6 starts communication on the route (1)-(3)-(5), the gateway device (ANS-GW) 12-1 # 2 A bit error rate (BER) is measured and periodically stored in the memory as a bit error rate MMM per unit time as an actual measurement value.

  Also, in the gateway device (ANS-GW) 12-1 # 2, a bit error rate reference value LLL and a continuous cycle count NNN which are triggers for executing the R3 relocation processing are set in the memory in advance. The number of consecutive cycles is a threshold value of the number of consecutive cycles in which the bit error rate MMM of the actual measurement value per unit time is a value equal to or less than the relocation bit error rate reference value LLL.

  The gateway device (ANS-GW) 12-1 # 2 periodically compares the bit error rate reference value LLL and the actually measured bit error rate MMM per unit time, and the actually measured bit error rate MMM per unit time is When the cycle that is smaller than the bit error rate reference value LLL exceeds the set number of consecutive cycles NNN, R3 relocation processing is executed, and route (1)-(3)-(5) is routed to route (4) -Change to (5).

FIG. 7 is an explanatory diagram of the seventh embodiment, in which the mobile device (subscriber terminal) 12-6 is controlled by the base station device # 2 (subordinate station ) from the base station device # 1 (BS) 12-2 # 1. BS) 12-2 # moves under the 2, communication path (1) - (3) - (from the time of starting the communication by 5), the gateway device # 1 (ANS-GW # 1 ) 12-1 # and starts measuring the elapsed time at 1, if it is determined that has elapsed variably relocation latency EEE as defined previously, the gateway device # 1 (ANS-GW # 1 ) 12-1 # 1 , the execution of the R3 relocation process Thus, the communication paths (1)-(3)-(5) are changed to the communication paths (4)-(5) that do not pass through the gateway device # 1 .

  An eighth embodiment is shown in FIG. After the moved mobile device (subscriber terminal) 12-6 starts communication on the route (1)-(3)-(5), the gateway device (ANS-GW) 12-1 # 1 A bit error rate (BER) is measured and periodically stored in the memory as a bit error rate MMM per unit time as an actual measurement value.

  The gateway device (ANS-GW) 12-1 # 1 is set in advance with a bit error rate reference value LLL and a continuous cycle number NNN as a reference for a trigger for executing the R3 relocation processing. The number of continuous cycles is a threshold of the number of cycles in which the bit error rate MMM of the actual measurement value per unit time becomes a value equal to or less than the bit error rate reference value LLL.

  The gateway device (ANS-GW) 12-1 # 1 periodically compares the bit error rate reference value LLL and the actual measured bit error rate MMM per unit time, and the actual measured bit error rate per unit time. When the number of cycles in which the MMM is smaller than the bit error rate reference value LLL exceeds the set number of consecutive cycles NNN, R3 relocation processing is executed, and routes (1)-(3)-(5) are routed. Change to (4)-(5).

  A ninth embodiment is shown in FIG. When a failure occurs in the gateway device (ANS-GW) 12-1 # 1 after the mobile device (subscriber terminal) 12-6 has started communication on the route (1)-(3)-(5) The gateway device (ANS-GW) 12-1 # 1 detects the occurrence of the failure by the failure detection means, and executes the R3 relocation processing if the R3 relocation processing is possible, and the route (1)-(3 )-(5) is changed to route (4)-(5).

  A tenth embodiment is shown in FIG. After the moved mobile device (subscriber terminal) 12-6 starts communication on the route (1)-(3)-(5), a restart process occurs in the gateway device (ANS-GW) 12-1 # 1. In such a case, the gateway device (ANS-GW) 12-1 # 1 detects the occurrence of the restart process by the restart process detection means, and if the R3 relocation process is possible, executes the R3 relocation process, 1)-(3)-(5) is changed to route (4)-(5).

  FIG. 11 shows the configuration of the gateway device 12. The gateway device 12 includes a layer 2 switch 11-1, a user signal processing unit (U-Plane) 11-2, and a control signal processing unit (C-Plane) 11-3. The layer 2 switch 11-1 has a layer 2 switch function in connection with an access service network (ASN) and a core service network (CSN).

  The user signal processing unit (U-Plane) 11-2 has a function of processing a user signal. The control signal processing unit (C-Plane) 11-3 has a function of processing control signals of the R3 interface, the R4 interface, and the R6 interface. The control signal processing unit (C-Plane) 11-3 detects the trigger of the R3 relocation process, and executes the R3 relocation procedure according to the WiMAX standard specification.

Regarding the above embodiment, the following additional notes are disclosed.
(Supplementary note 1) The core service network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
In the access network gateway device that passes only through the second communication path, the storage means for measuring the total amount of processing data per unit time and storing it in a memory;
A determination unit that compares a preset reference value with the value of the total processing data amount and determines whether the value of the total processing data amount is smaller than the preset reference value;
An activation unit that activates the relocation process when the determination unit determines that the value of the total processing data amount is smaller than the preset reference value;
An access network gateway device comprising:
(Supplementary Note 2) The core communication network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
A storage means for monitoring the number of simultaneous connections with the core service network in an access network gateway device that passes only through the second communication path, and storing the value of the number of simultaneous connections in a memory;
A determination unit that compares a reference value set in advance with the value of the number of simultaneous connections, and determines whether the value of the number of simultaneous connections is smaller than the preset reference value;
An activation unit that activates the relocation process when the determination unit determines that the value of the number of simultaneous connections is smaller than the preset reference value;
An access network gateway device comprising:
(Supplementary Note 3) The core communication network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
A storage that monitors the number of simultaneous connections with the other access network gateway apparatus in the access network gateway apparatus that passes only through the second communication path, and stores the value of the number of simultaneous connections in a memory Means,
A determination unit that compares a reference value set in advance with the value of the number of simultaneous connections, and determines whether the value of the number of simultaneous connections is larger than the preset reference value;
An activation unit that activates the relocation process when the determination unit determines that the value of the number of simultaneous connections is greater than the preset reference value;
An access network gateway device comprising:
(Supplementary Note 4) The core communication network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
In the access network gateway device that passes only through the second communication path, time measuring means for measuring an elapsed time from the start of communication through the first communication path;
Determining means for determining whether or not the elapsed time exceeds a predetermined standby time;
An activation unit that activates the relocation process when the determination unit determines that the elapsed time has exceeded the predetermined standby time;
An access network gateway device comprising:
(Supplementary Note 5) The core communication network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
In the access network gateway device that passes only through the second communication path, the memory usage rate or CPU usage rate of its own device is measured, and the storage means for storing the actual measurement result;
A determination unit that compares a reference value set in advance with the memory usage rate or the CPU usage rate, and determines whether the value of the memory usage rate or the CPU usage rate is smaller than the preset reference value;
An activation unit that activates the relocation process when the determination unit determines that the value of the memory usage rate or the CPU usage rate is smaller than the preset reference value;
An access network gateway device comprising:
(Supplementary Note 6) The core communication network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
A storage means for measuring a bit error rate of communication of the first communication path in an access network gateway device that passes only through the second communication path, and storing the value of the bit error rate in a memory;
A determination unit that compares a reference value set in advance with the value of the bit error rate, and determines whether the value of the bit error rate is smaller than the reference value set in advance;
An activation unit that activates the relocation process when the determination unit determines that the value of the bit error rate is smaller than the preset reference value;
An access network gateway device comprising:
(Supplementary note 7) The core communication network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
A time measuring means for measuring an elapsed time from the start time of communication through the first communication path in the access network gateway device that passes through the first communication path and does not pass through the second communication path;
Determining means for determining whether or not the elapsed time exceeds a predetermined standby time;
An activation unit that activates the relocation process when the determination unit determines that the elapsed time has exceeded the predetermined standby time;
An access network gateway device comprising:
(Supplementary note 8) The core communication network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
The access network gateway device that passes through the first communication path and does not pass through the second communication path measures the bit error rate of communication on the first communication path, and calculates the value of the bit error rate. Storage means for storing in memory;
A determination unit that compares a reference value set in advance with the value of the bit error rate, and determines whether the value of the bit error rate is smaller than the reference value set in advance;
An activation unit that activates the relocation process when the determination unit determines that the value of the bit error rate is smaller than the preset reference value;
An access network gateway device comprising:
(Supplementary note 9) The core communication network is connected to the access service network, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
A detecting means for detecting the occurrence of a failure in the own device in the access network gateway device via the first communication path and not via the second communication path;
An activation unit that activates the relocation process when a failure occurrence is detected by the detection unit;
An access network gateway device comprising:
(Supplementary Note 10) The core communication network and the access service network are connected, and the first communication path via the other access network gateway device associated with the hand-over of the mobile device is connected to the other access network. In an access network gateway apparatus having a function of relocation processing for changing to a second communication path not via a network gateway apparatus,
Detecting means for detecting occurrence of resumption processing in the own apparatus in the access network gateway apparatus that passes through the first communication path and does not pass through the second communication path;
An activation unit that activates the relocation process when the detection unit detects the occurrence of the restart process;
An access network gateway device comprising:

It is a figure which shows 1st Embodiment. It is a figure which shows 2nd Embodiment. It is a figure which shows 3rd Embodiment. It is a figure which shows 4th Embodiment. It is a figure which shows 5th Embodiment. It is a figure which shows 6th Embodiment. It is a figure which shows 7th Embodiment. It is a figure which shows 8th Embodiment. It is a figure which shows 9th Embodiment. It is a figure which shows 10th Embodiment. It is a figure which shows the structural example of a gateway apparatus. It is a figure which shows the network structural example of mobile WiMAX. It is explanatory drawing of the relocation in a WiMAX network.

Explanation of symbols

12-1 # 1, # 2 Access network gateway device (ANS-GW)
12-2 # 1, # 2 Base station equipment (BS)
12-3 Service Provider Device 12-4 Authentication Server 12-5 Home Agent 12-6 Mobile Station (Subscriber Terminal)

Claims (1)

Connecting the core service network and the access service network and connecting the first communication path via the other access network gateway device associated with the hand-over of the mobile station to the other access network gateway device In an access network gateway device having a function of relocation processing for changing to a second communication path not via
A time measuring means for measuring an elapsed time from a start time of communication through the first communication path in an access network gateway device corresponding to a position passing through only the second communication path ;
Determining means for determining whether or not the elapsed time measured by the time measuring means has exceeded a predetermined standby time;
The to the judgment exceeds a waiting time during which the elapsed time is the predefined by determination means, the access network gateway device being characterized in that a starting means for starting the relocation process.

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