CN115208517A

CN115208517A - Method and device for coding flow indication graph

Info

Publication number: CN115208517A
Application number: CN202210827657.XA
Authority: CN
Inventors: 童娣; 李宛苡
Original assignee: Shenzhen Lianping Semiconductor Co ltd
Current assignee: Shenzhen Lianping Semiconductor Co ltd
Priority date: 2022-07-14
Filing date: 2022-07-14
Publication date: 2022-10-18
Anticipated expiration: 2042-07-14
Also published as: CN115208517B

Abstract

The application provides a coding method and a coding device of a flow indication graph. The method comprises the following steps: obtaining a DTIM count, the number of first STAs and first AIDs corresponding to the first STAs, wherein the first STAs are the STAs with cache data at the AP; and splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs and each first AID, so that each first AID has a corresponding start identification field and an end identification field, and the start identification field and the end identification field are used for representing a byte interval of a byte position where each first AID is located. According to the method and the device, the AIDs of the STAs needing to be indicated are split, the split parts are divided into the bytes in the interval near the bytes where the AIDs of the STAs needing to be indicated are located, and a plurality of partial virtual bitmaps are formed, so that the number of bytes can be saved, resources are saved, and the problem that resources are wasted under the condition that the AIDs of the STAs needing to be indicated in the partial virtual bitmaps in the prior art are scattered is solved.

Description

Method and device for coding flow indication graph

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and an apparatus for encoding a traffic indication map, a computer-readable storage medium, a processor, and an electronic device.

Background

The TIM (Traffic Indication Map) element is used to indicate to an associated STA (Station) a DTIM (Delivery Traffic Indication Map) count, a DTIM period, and whether it has buffered Traffic at an AP (Access Point) or not. The traffic buffer indication is mainly realized by bitmap control and partial virtual bitmaps.

If the AIDs (Association identifiers) of the STAs that need to be indicated in the partial virtual bitmap are very scattered, a large number of indication bytes are wasted. For example, when STA AID1 and STA AID88 need to be indicated, the partial virtual bitmap may include a traffic indication virtual bitmap from byte 0 to byte 11, and STAs included in the middle bytes 1 to 10 have no buffered traffic at the AP, that is, the corresponding bit value is 0, and these indication bytes are wasted.

Therefore, an efficient method for encoding the traffic indication map is needed.

The above information disclosed in this background section is only for enhancement of understanding of the background of the technology described herein and, therefore, certain information may be included in the background that does not form the prior art that is already known in this country to a person of ordinary skill in the art.

Disclosure of Invention

The present application mainly aims to provide an encoding method and apparatus of a traffic indication map, a computer-readable storage medium, a processor, and an electronic device, so as to solve the problem that resources are wasted in the case that AIDs of STAs that need to be indicated in a partial virtual bitmap are scattered in the prior art.

In order to achieve the above object, according to an aspect of the present application, there is provided an encoding method for a traffic indication map, where the traffic indication map at least includes a DTIM count field, a bitmap control field, and a partial virtual bitmap field, the bitmap control field includes a traffic indication bit and a bitmap offset bit, and the partial virtual bitmap field includes at least one AID, including: obtaining a DTIM count, the number of first STAs and first AIDs corresponding to the first STAs, wherein the first STAs are the STAs with cache data at an AP; splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs and each first AID, so that each first AID has a corresponding start identification field and an end identification field, and the start identification field and the end identification field are used for representing a byte interval of a byte position where each first AID is located.

Further, the type of the AID includes the first AID and a second AID, the STA corresponding to the second AID does not have cached data in the AP, the DTIM count includes two cases, which are 0 and not 0, and the splitting is performed on the partial virtual bitmap field according to the DTIM count, the number of the first STA, and the first AID includes: acquiring the number of bytes of the second AID between any two adjacent first AIDs to obtain at least one first number of bytes under the condition that the number of the first STAs is greater than or equal to 2; splitting the partial virtual bitmap field if the DTIM count and at least one of the first number of bytes satisfy a first predetermined condition, the first predetermined condition comprising: the DTIM count is 0, each first byte number is greater than 2, the DTIM count is not 0, a first byte number is greater than 3, the DTIM count is not 0, and an nth first byte number is greater than 2, where the first byte number is the first byte number between two adjacent first AIDs, N is a positive integer greater than or equal to 2, and the nth first byte number is the first byte number between any two adjacent first AIDs after the second first AID.

Further, in a case that the DTIM count and at least one of the first number of bytes satisfy a first predetermined condition, splitting the partial virtual bitmap field includes: under the first predetermined condition that the DTIM count is not 0 and the first number of bytes is greater than 3, or the DTIM count is not 0 and the nth number of bytes is greater than 2, marking the traffic indication bit as a fragmentation indication bit, where the fragmentation indication bit has a value of 1, and adding the end identification field before the first AID, and adding the start identification field and the end identification field before each first AID after the first AID.

Further, in a case that the DTIM count and at least one of the first number of bytes satisfy a first predetermined condition, splitting the partial virtual bitmap field includes: and when the first predetermined condition is that the DTIM count is 0 and each first byte number is greater than 2, adding the end identification field before a first one of the first AIDs, and adding the start identification field and the end identification field before each first AID after the first one of the first AIDs.

Further, the method further comprises: not splitting the partial virtual bitmap field if the DTIM count and at least one of the first number of bytes do not satisfy the first predetermined condition.

Further, the method further comprises: and under the condition that the number of the first STAs is less than 2, the partial virtual bitmap field is not split.

Further, not splitting the partial virtual bitmap field includes: under the condition that the DTIM count is not 0, marking the flow indicating bit as a fragmentation indicating bit, wherein the value of the fragmentation indicating bit is 0; and under the condition that the DTIM count is 0, adding the ending identification field after the bitmap control field.

Further, the method further comprises: determining whether the DTIM count is 0 if the number of the first STAs is less than 2; and under the condition that the DTIM count is not 0, controlling the flow indicating bit to be combined with the bitmap offset bit to obtain a target bitmap offset, wherein the target bitmap offset is used for representing the starting bytes of the partial virtual bitmap.

According to another aspect of the present application, an encoding apparatus of a traffic indication map is provided, where the traffic indication map at least includes a DTIM count field, a bitmap control field, and a partial virtual bitmap field, the bitmap control field includes a traffic indication bit and a bitmap offset bit, the partial virtual bitmap field includes at least one AID, and includes an obtaining unit and a splitting unit, where the obtaining unit is configured to obtain a DTIM count, the number of first STAs, and first AIDs corresponding to the first STAs, and the first STAs are STAs having cached data at an AP; the splitting unit is configured to split the partial virtual bitmap field according to the DTIM count, the number of the first STAs, and the first AID, so that the first AID has a start identification field and an end identification field corresponding to the first AID, and the start identification field and the end identification field are used to represent byte positions where the first AID is located.

According to yet another aspect of the present application, a computer-readable storage medium is provided, which includes a stored program, wherein the program when executed controls a device in which the computer-readable storage medium is located to perform any one of the methods for encoding the traffic indication map.

According to a further aspect of the present application, there is provided a processor for executing a program, wherein the program executes any one of the methods for encoding a traffic indication map.

According to another aspect of the present application, there is provided an electronic device including: one or more processors, memory, a display device, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including code for performing any of the described flow indication maps.

By applying the technical scheme of the application, in the encoding method of the flow indication map, firstly, a DTIM count, the number of first STAs and first AIDs corresponding to the first STAs are obtained, wherein the first STAs are STAs with cache data at an AP; and then splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs and each first AID, so that each first AID has a corresponding start identification field and an end identification field, and the start identification field and the end identification field are used for representing a byte interval of a byte position where each first AID is located. According to the method, a large number of indication byte numbers can be wasted under the condition that AIDs of the STAs needing to be indicated in the partial virtual bitmap are scattered, the AIDs of the STAs needing to be indicated are split into bytes in an interval near the bytes where the AIDs of the STAs needing to be indicated are located, and a plurality of partial virtual bitmaps are formed, so that the byte numbers can be saved, resources are saved, and the problem that resources are wasted under the condition that the AIDs of the STAs needing to be indicated in the partial virtual bitmaps in the prior art are scattered is solved.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this application, are included to provide a further understanding of the application, and the description of the exemplary embodiments and illustrations of the application are intended to explain the application and are not intended to limit the application. In the drawings:

fig. 1 shows a flow chart of a method of encoding a traffic indication map according to an embodiment of the application;

fig. 2 shows a schematic diagram of an encoding apparatus of a traffic indication map according to an embodiment of the present application.

Detailed Description

It should be noted that, in the present application, the embodiments and features of the embodiments may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

In order to make the technical solutions better understood by those skilled in the art, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only partial embodiments of the present application, but not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

It should be noted that the terms "first," "second," and the like in the description and claims of this application and in the drawings described above are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances in order to facilitate the description of the embodiments of the application herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

It will be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present. Also, in the specification and claims, when an element is described as being "connected" to another element, the element may be "directly connected" to the other element or "connected" to the other element through a third element.

As mentioned in the background of the invention, in order to solve the above problem, in the prior art, a method and an apparatus for encoding a traffic indication map, a computer-readable storage medium, a processor, and an electronic device are provided in an exemplary embodiment of the present application.

According to an embodiment of the present application, there is provided an encoding method for a traffic indication map, where the traffic indication map at least includes a DTIM count field, a bitmap control field, and a partial virtual bitmap field, the bitmap control field includes a traffic indication bit and a bitmap offset bit, and the partial virtual bitmap field includes at least one AID.

Fig. 1 is a flowchart of a method for encoding a traffic indication map according to an embodiment of the present application. As shown in fig. 1, the method comprises the steps of:

step S101, obtaining a DTIM count, the number of first STAs and first AIDs corresponding to the first STAs, wherein the first STAs are the STAs with cache data at an AP;

and step S102, splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs, and each first AID, so that each first AID has a start identifier field and an end identifier field corresponding thereto, where the start identifier field and the end identifier field are used to represent a byte section of a byte position where each first AID is located.

In the encoding method of the traffic indicator map, firstly, a DTIM count, the number of first STAs and a first AID corresponding to the first STA are obtained, where the first STA is an STA having cached data at an AP; and then splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs and each first AID, so that each first AID has a corresponding start identification field and an end identification field, and the start identification field and the end identification field are used for representing a byte section of a byte position where each first AID is located. According to the method, the AIDs of the STAs needing to be indicated are split into bytes in an interval near the bytes where the AIDs of the STAs needing to be indicated are located, and a plurality of partial virtual bitmaps are formed, so that the number of bytes can be saved, resources are saved, and the problem that resources are wasted under the condition that the AIDs of the STAs needing to be indicated in the partial virtual bitmaps in the prior art are scattered is solved.

It should be noted that the steps illustrated in the flowcharts of the figures may be performed in a computer system such as a set of computer-executable instructions and that, although a logical order is illustrated in the flowcharts, in some cases, the steps illustrated or described may be performed in an order different than presented herein.

In practical applications, the TIM is a basic structure of a traffic indication bitmap, a format of a TIM element in the prior art is shown in table 1, a standard TIM only indicates unicast information cached by an AP, and a DTIM is a special TIM which indicates multicast information cached by an AP in addition to the cached unicast information. Generally, each Beacon frame includes a TIM, and the TIM is specifically not a DTIM, and needs to be determined according to two parameters, namely a DTIM count and a DTIM period. The DTIM count indicates how many Beacon frames (including the current Beacon frame) before the next DTIM arrives, for example, if the DTIM count is 0, the current TIM is a DTIM. The DTIM period field indicates the number of Beacon frames between two consecutive DTIMs. For example, if all TIMs are DTIMs, a DTIM period equal to 1 and a DTIM period equal to 0 are reserved. The bitmap control field has a length of 0 or 1 byte, and the format of the bitmap control field in the prior art is shown in table 2.

Table 1 format of TIM element in prior art

Name of field

Element ID

Length of

DTIM counting

DTIM period

Bitmap control

Partial virtual bitmap

Byte number

1

0 or 1

0-251

Table 2 format of bitmap control field in prior art

Name of field	Flow indication	Bitmap offset
			Number of bits	1	7

In an embodiment of the application, the type of the AID includes the first AID and a second AID, the STA corresponding to the second AID does not have cached data in the AP, the DTIM count includes two cases, that is, 0 and not 0, and the splitting is performed on the partial virtual bitmap field according to the DTIM count, the number of the first STAs, and the first AID includes: acquiring the number of bytes of the second AID between any two adjacent first AIDs to obtain at least one first number of bytes when the number of the first STAs is greater than or equal to 2; splitting the partial virtual bitmap field when the DTIM count and at least one of the first byte number satisfy a first predetermined condition, where the first predetermined condition includes: the DTIM count is 0, each of the first byte numbers is greater than 2, the DTIM count is not 0, a first one of the first byte numbers is greater than 3, the DTIM count is not 0, and an nth one of the first byte numbers is greater than 2, where a first one of the first byte numbers is the first byte number between first two adjacent first AIDs, N is a positive integer greater than or equal to 2, and an nth one of the first byte numbers is the first byte number between any two adjacent first AIDs after a second one of the first AIDs. When the number of the STAs is large, the number of the STAs is determined by determining the distribution of the AIDs corresponding to the STAs with cached data at the AP, that is, determining the number of bytes of the second AID between two adjacent first AIDs to determine whether to split the partial virtual bitmap, so as to further reduce the waste of resources.

In order to facilitate a subsequent STA to analyze a TIM element in a Beacon frame, when a DTIM count is not 0, a traffic indicator bit is marked as a fragmentation indicator bit, in another embodiment of the present application, when the DTIM count and at least one first byte number satisfy a first predetermined condition, splitting the partial virtual bitmap field includes: when the first predetermined condition is that the DTIM count is not 0 and the first byte number is greater than 3, or the DTIM count is not 0 and the nth first byte number is greater than 2, the flow indicator bit is marked as a fragmentation indicator bit having a value of 1, the end flag field is added before the first AID, and the start flag field and the end flag field are added before each first AID subsequent to the first AID. The fragment indicating bit is used for representing whether the partial virtual bitmap is split or not, and if the value of the fragment indicating bit is 1, the partial virtual bitmap is split. The start identification field and the end identification field are used for identifying a byte section where a first AID following the first AID is located, and the start identification field of the first AID is a bitmap offset in the bitmap control field. The start identification field and the end identification field are both 1 byte long.

In practical application, for a TIM element whose DTIM count is not 0, that is, non-DTIM, the format of the bitmap control field in the TIM element is shown in table 3, where a traffic indication bit in the bitmap control field is reserved and used as a fragmentation indication bit, and when the number of first STAs is greater than or equal to 2, a first AID of a kth first STA that records buffered traffic at the AP is X _k : for the case of k =2, if

Splitting a partial virtual bitmap for the first STA and the second first STA for k>2, if

The partial virtual bitmap for the kth first STA and the k-1 st first STA is split, wherein,

indicating a rounding down.

TABLE 3 bitmap control field Format for TIM element with DTIM count not 0

Name of field	Fragmentation indication	Bitmap offset
			Number of bits	1	7

Specifically, for the traffic indication bitmaps of the first STA and the second first STA, if the split processing is performed (that is, there are two partial virtual bitmaps to indicate the traffic buffering situation), three more bytes are added, which are the end identification field of the first split partial virtual bitmap, the start identification field of the second split partial virtual bitmap, and the end identification field of the second split partial virtual bitmap, respectively. Therefore, when the number of bytes between the number of bytes of the first STA and the number of bytes of the second first STA is greater than 3, splitting is performed with fewer resources than the original indication method. And for the kth STA and the (k-1) th STA, k >2, two more bytes are added each time splitting is carried out, and the two more bytes are respectively a start identification field and an end identification field of the added split partial virtual bitmap. Therefore, when the number of bytes between the number of bytes of the kth STA and the number of bytes of the (k-1) th STA is greater than 2, splitting is performed with less resources than the original indication method. The start identification field may be a bitmap start offset field, the end identification field may be a bitmap end offset field or a sub-bitmap length field, as shown in tables 4 and 5, table 4 is to split a partial virtual bitmap when the DTIM count is not 0, and split the partial virtual bitmap into at least two partial virtual bitmaps, the end identification field is a TIM element format of the bitmap end offset field, table 5 is to split a partial virtual bitmap when the DTIM count is not 0, and the end identification field is a TIM element format of the sub-bitmap length field.

Table 4 TIM element format for splitting partial virtual bitmap when DTIM count is not 0

Table 5 another TIM element format for splitting a partial virtual bitmap when the DTIM count is not 0

In another embodiment of the present application, when the DTIM count and at least one of the first number of bytes satisfy a first predetermined condition, splitting the partial virtual bitmap field includes: when the first predetermined condition is that the DTIM count is 0 and the first byte count is greater than 2, the end flag field is added before the first AID, and the start flag field and the end flag field are added before the first AID after the first AID. When the DTIM count is 0, the traffic indication field is used to indicate whether an STA associated with AID 0 in the partial virtual bitmap has cached data at the AP, and by adding an end identifier field before the first AID, the STA may determine whether a subsequent partial virtual bitmap field is split when parsing the TIM element, that is, after parsing the subsequent partial virtual bitmap according to the end identifier field before the first AID, if it is determined that the element has not been parsed according to the length field in the TIM element, it may be determined whether there are fragments of the subsequent partial virtual bitmap.

In practical applications, for a TIM element with a DTIM count of 0, since 1 bit is needed as a traffic indication field to indicate whether one or more multicast or broadcast frames are buffered at an AP, the traffic indication bit in the bitmap control field may no longer be used as a fragmentation indication subfield, and for the DTIM, the bitmap control field is always followed by an end identification field, which may be a bitmap end offset field or a sub-bitmap length field, and the format of the end identification field being a bitmap end offset field is shown in table 6.

Table 6 TIM element format for splitting partial virtual bitmap with DTIM count of 0

Specifically, for the case where the number of STAs is 2 or more, if

The partial virtual bitmap for the kth STA and the (k-1) th STA is split. This advantage of saving resources is greater if the AIDs of STAs that need to be instructed to buffer traffic are more scattered.

In a specific embodiment of the present application, a fragmentation indication field is added after a bitmap control field, a value of the fragmentation indication field includes a first symbol and a second symbol, and the fragmentation indication field is the first symbol and indicates that no partial virtual bitmap is split, and only one partial virtual bitmap indicates a traffic cache condition; and if the fragment indicating bit is a second symbol, the fragment indicating bit indicates that the partial virtual bitmap is fragmented, and at least two partial virtual bitmaps behind the fragment indicating bit indicate the flow cache condition. If the slice indication bit in the slice indication field is the second symbol, the format of the end identification field being a bitmap end offset field is shown in table 7.

Table 7 another TIM element format for splitting a partial virtual bitmap with a DTIM count of 0

Specifically, for the case where the number of STAs is 2 or more, for the case where k =2, if

Splitting partial virtual bitmaps of a first STA and a second first STA; for k>2, if

The partial virtual bitmap for the kth STA and the (k-1) th STA is split. In this embodiment, the length required by the DTIM without splitting is one byte longer than the length of the DTIM defined by the protocol, and if the AIDs of the STAs to be indicated are more distributed and need to be split, the traffic indication encoding method in this embodiment is better than the scheme in the protocol, and the advantage is more obvious when the AIDs are more distributed.

In order to further save resources, in another embodiment of the present application, the method further includes: and under the condition that the DTIM count and at least one first byte number do not meet the first preset condition, not splitting the partial virtual bitmap field.

In another embodiment of the present application, the method further includes: and under the condition that the number of the first STAs is less than 2, the partial virtual bitmap field is not split. When the number of the first STA is less than 2, the first STA is not split, and resources are saved.

In order to make the traffic indication coding formats consistent under different conditions, in another embodiment of the present application, the not splitting the partial virtual bitmap field includes: under the condition that the DTIM count is not 0, marking the flow indicating bit as a fragmentation indicating bit, wherein the value of the fragmentation indicating bit is 0; when the DTIM count is 0, the end flag field is added after the bitmap control field.

In practical application, when the DTIM count is not 0, since the traffic indication bit in the bitmap control field is reserved, the traffic indication bit is used as a fragmentation indication bit, the fragmentation indication bit is 0 to indicate that no partial virtual bitmap is split, only one partial virtual bitmap indicates traffic caching, if only zero or one STA has cached traffic at the AP, splitting is not required, and the TIM element format is shown in table 8. When the DTIM count is 0, 1 bit is needed as a traffic indication field to indicate whether one or more multicast or broadcast frames are cached at the AP, so that the traffic indication bit in the bitmap control field may not be used as the fragmentation indication subfield any more, additional information is needed to indicate whether fragmentation is performed, an end identification field may be added after the bitmap control field, the TIM element format is shown in table 9, or a fragmentation indication field may be added after the bitmap control field, where the fragmentation indication field indicates that a part of the virtual bitmap is not fragmented for the first symbol, and the TIM element format is shown in table 10.

Table 8 TIM element format with partial virtual bitmap not split when DTIM count is not 0

Table 9 TIM element format with DTIM count of 0 without splitting partial virtual bitmap

Table 10 another TIM element format with DTIM count of 0 without splitting partial virtual bitmap

In order to make the value of the bitmap offset indicating the partial virtual bitmap larger, in another embodiment of the present application, the method further includes: determining whether the DTIM count is 0 or not when the number of the first STAs is less than 2; and under the condition that the DTIM count is not 0, controlling the flow indication bit to be combined with the bitmap offset bit to obtain a target bitmap offset, wherein the target bitmap offset is used for representing the starting byte of the partial virtual bitmap.

Specifically, when the bitmap offset is set to K, that is, the partial virtual bitmap is indicated to start from K × 2 bytes, which is denoted as N1, and N2 is the last byte number indicated by the partial virtual bitmap. That is, the traffic virtual bitmaps for workstations with AIDs of 1 to N1 × 8-1 and (N2 + 1) × 8 to 2007 are all 0. The length of the partial virtual bitmap field is 0-251 bytes, that is, the partial virtual bitmap field contains 2008 bits at most, the value of bit N (1 ≦ N ≦ 2007) in the bitmap indicates whether the STA with AID N has cache traffic at the AP, 1 represents that there is cache, and 0 represents that there is no cache. The 0 bit is a reserved field and is not allocated to a node to represent all multicast and broadcast. Since the indication partial virtual bitmap starts from K × 2 bytes, that is, the number of starting bytes of the partial virtual bitmap is always even, when the number of bytes of the AID of the STA to be indicated is odd, an indication byte number is wasted. In the above embodiment, for the TIM element whose DTIM count is not 0, since the traffic indication bit in the bitmap control field is reserved, it may also be used as a bitmap offset bit. That is, a total of 8 bits is used to indicate the bitmap offset, and when the bitmap offset is set to K, that is, the partial virtual bitmap is indicated to start from K bytes, that is, when the number of bytes where the AID of the STA that needs to be indicated is an odd number, one indicated byte is saved.

In practical applications, the above method may be used when the number of the first STAs is greater than or equal to 2.

An embodiment of the present application further provides an encoding apparatus of a traffic indication map, where the traffic indication map at least includes a DTIM count field, a bitmap control field, and a partial virtual bitmap field, where the bitmap control field includes a traffic indication bit and a bitmap offset bit, and the partial virtual bitmap field includes at least one AID. The following describes an encoding apparatus of a traffic indication map provided in an embodiment of the present application.

Fig. 2 is a schematic diagram of an encoding device of a traffic indication map according to an embodiment of the present application. As shown in fig. 2, the apparatus includes:

an obtaining unit 10, configured to obtain a DTIM count, a number of first STAs, and a first AID corresponding to the first STA, where the first STA is an STA having cached data at an AP;

a splitting unit 20, configured to split the partial virtual bitmap field according to the DTIM count, the number of the first STAs, and the first AID, so that the first AID has a start identifier field and an end identifier field corresponding to the first AID, where the start identifier field and the end identifier field are used to represent byte positions where the first AID is located.

In the encoding apparatus for the traffic indicator map, the obtaining unit obtains a DTIM count, a number of first STAs and a first AID corresponding to the first STA, where the first STA is an STA having cached data at an AP; and splitting the partial virtual bitmap field by the splitting unit according to the DTIM count, the number of the first STAs and each first AID, so that each first AID has a corresponding start identification field and an end identification field, and the start identification field and the end identification field are used for representing a byte interval of a byte position where each first AID is located. A large number of indication bytes can be wasted under the condition that AIDs of STAs needing to be indicated in a partial virtual bitmap are scattered, the device splits the AIDs of the STAs needing to be indicated into bytes in an interval near the bytes where the AIDs of the STAs needing to be indicated are located, and a plurality of partial virtual bitmaps are formed, so that the number of bytes can be saved, resources are saved, and the problem that resources are wasted under the condition that the AIDs of the STAs needing to be indicated in the partial virtual bitmaps in the prior art are scattered is solved.

In practical applications, the TIM is a basic structure of a traffic indication bitmap, a format of a TIM element in the prior art is shown in table 11, a standard TIM indicates only unicast information buffered by an AP, and a DTIM is a special TIM which indicates multicast information buffered by an AP in addition to the buffered unicast information. Generally, each Beacon frame includes a TIM, and the TIM is determined according to two parameters, namely, a DTIM count and a DTIM period if the TIM is not a DTIM. The DTIM count indicates how many Beacon frames (including the current Beacon frame) before the next DTIM arrives, for example, if the DTIM count is 0, the current TIM is a DTIM. The DTIM period field indicates the number of Beacon frames between two consecutive DTIMs. For example, if all TIMs are DTIM, a DTIM period equal to 1 and a DTIM period equal to 0 are reserved. The bitmap control field has a length of 0 or 1 byte, and the format of the bitmap control field in the prior art is shown in table 2.

TABLE 11 format of TIM element in the prior art

Name of field

Element ID

Length of

DTIM counting

DTIM period

Bitmap control

Partial virtual bitmap

Number of bytes

1

0 or 1

0-251

Table 12 format of bitmap control field in prior art

Name of field	Flow indication	Bitmap offset
			Number of bits	1	7

In an embodiment of the application, the type of the AID includes the first AID and a second AID, the STA corresponding to the second AID does not have buffered data in the AP, the DTIM count includes two cases, that is, 0 and not 0, and the splitting unit includes an obtaining module and a splitting module, where the obtaining module is configured to obtain, when the number of the first STA is greater than or equal to 2, the number of bytes of the second AID between any two adjacent first AIDs, and obtain at least one first number of bytes; the splitting module is configured to split the partial virtual bitmap field when the DTIM count and at least one of the first number of bytes satisfy a first predetermined condition, where the first predetermined condition includes: the DTIM count is 0, each of the first byte numbers is greater than 2, the DTIM count is not 0, a first one of the first byte numbers is greater than 3, the DTIM count is not 0, and an nth one of the first byte numbers is greater than 2, where a first one of the first byte numbers is the first byte number between first two adjacent first AIDs, N is a positive integer greater than or equal to 2, and an nth one of the first byte numbers is the first byte number between any two adjacent first AIDs after a second one of the first AIDs. When the number of the STAs is large, the number of the STAs is determined by determining the distribution of the AIDs corresponding to the STAs with cached data at the AP, that is, determining the number of bytes of the second AID between two adjacent first AIDs to determine whether to split the partial virtual bitmap, so as to further reduce the waste of resources.

In order to facilitate subsequent STAs to parse a TIM element in a Beacon frame, when the DTIM count is not 0, the flow indication bit is marked as a fragmentation indication bit, in another embodiment of the present application, the fragmentation module includes a first fragmentation sub-module, where the first fragmentation sub-module is configured to mark the flow indication bit as a fragmentation indication bit when the first predetermined condition is that the DTIM count is not 0 and a first number of bytes is greater than 3, or the DTIM count is not 0 and an nth number of bytes is greater than 2, where a value of the fragmentation indication bit is 1, add the end identification field before a first AID, and add the start identification field and the end identification field before each first AID after the first AID. The fragment indicating bit is used for representing whether the partial virtual bitmap is split or not, and if the value of the fragment indicating bit is 1, the partial virtual bitmap is split. The start identification field and the end identification field are used for identifying a byte section where a first AID following the first AID is located, and the start identification field of the first AID is a bitmap offset in the bitmap control field. The start identification field and the end identification field are both 1 byte long.

In practical applications, for TIM elements whose DTIM count is not 0, that is, non-DTIM, the format of the bitmap control field in the TIM element is shown in table 13, where the traffic indication bit in the bitmap control field is reserved and used as a fragmentation indication bit, and when the number of first STAs is greater than or equal to 2, the first AID of the kth first STA remembering that there is buffered traffic at the AP is X _k : for the case of k =2, if

Then the partial virtual bitmap for the first STA and the second first STA are split for k>2, if

Splitting a partial virtual bitmap for the kth first STA and the (k-1) th first STA, wherein,

indicating a rounding down.

TABLE 13 bitmap control field format for TIM elements with DTIM count not 0

Name of field	Slice indication	Bitmap offset
			Number of bits	1	7

Specifically, for the traffic indication bitmaps of the first STA and the second first STA, if the split processing is performed (that is, there are two partial virtual bitmaps to indicate the traffic buffering situation), three more bytes are added, which are the end identification field of the first split partial virtual bitmap, the start identification field of the second split partial virtual bitmap, and the end identification field of the second split partial virtual bitmap, respectively. Therefore, when the number of bytes between the number of bytes of the first STA and the number of bytes of the second first STA is greater than 3, splitting is performed with fewer resources than the original indication method. And for the kth STA and the (k-1) th STA, k >2, two more bytes are added each time splitting is carried out, and the two more bytes are respectively a start identification field and an end identification field of the added split partial virtual bitmap. Therefore, when the number of bytes between the number of bytes of the kth STA and the number of bytes of the (k-1) th STA is greater than 2, splitting is performed with less resources than the original indication method. The start identification field may be a bitmap start offset field, the end identification field may be a bitmap end offset field or a sub-bitmap length field, as shown in table 14 and table 15, table 14 splits a partial virtual bitmap into at least two partial virtual bitmaps when the DTIM count is not 0, the end identification field is a TIM element format of the bitmap end offset field, table 15 splits a partial virtual bitmap when the DTIM count is not 0, and the end identification field is a TIM element format of the sub-bitmap length field.

Table 14 TIM element format for splitting partial virtual bitmap when DTIM count is not 0

Table 15 another TIM element format for splitting a partial virtual bitmap when the DTIM count is not 0

In another embodiment of the application, the splitting module includes a second splitting submodule, where the second splitting submodule is configured to, when the first predetermined condition is that the DTIM count is 0 and each of the first byte numbers is greater than 2, add the end identifier field before a first one of the first AIDs, and add the start identifier field and the end identifier field before each of the first AIDs after the first one of the first AIDs. When the DTIM count is 0, the traffic indication field is used to indicate whether an STA associated with AID 0 in the partial virtual bitmap has cached data at the AP, and by adding an end identifier field before the first AID, the STA may determine whether a subsequent partial virtual bitmap field is split when parsing the TIM element, that is, after parsing the subsequent partial virtual bitmap according to the end identifier field before the first AID, if it is determined that the element has not been parsed according to the length field in the TIM element, it may be determined whether there are fragments of the subsequent partial virtual bitmap.

In practical applications, for a TIM element with a DTIM count of 0, since 1 bit is needed as a traffic indication field to indicate whether one or more multicast or broadcast frames are buffered at an AP, the traffic indication bit in the bitmap control field may no longer be used as a fragmentation indication subfield, and for the DTIM, the bitmap control field is always followed by an end identification field, which may be a bitmap end offset field or a sub-bitmap length field, and the format of the end identification field is the bitmap end offset field is shown in table 16.

Table 16 TIM element format for splitting partial virtual bitmap with DTIM count of 0

Specifically, for the case where the number of STAs is 2 or more, if

In a specific embodiment of the present application, a fragmentation indication field is added after a bitmap control field, a value of the fragmentation indication field includes a first symbol and a second symbol, and the fragmentation indication field is the first symbol and indicates that no partial virtual bitmap is split, and only one partial virtual bitmap indicates a traffic cache condition; and if the fragment indicating bit is a second symbol, the fragment indicating bit indicates that the partial virtual bitmap is fragmented, and at least two partial virtual bitmaps behind the fragment indicating bit indicate the traffic caching condition. If the fragmentation indication bit in the fragmentation indication field is the second symbol, the end identification field is the bitmap end offset field, and the format is shown in table 17.

Table 17 another TIM element format for splitting partial virtual bitmaps with a DTIM count of 0

Splitting partial virtual bitmaps of the first STA and the second first STA; for k>2, if

The partial virtual bitmap for the kth STA and the (k-1) th STA is split. In this embodiment, the length required by the DTIM without splitting is one byte longer than the length of the DTIM defined by the protocol, and if the AIDs of the STAs to be indicated are scattered and splitting needs to be performed, the traffic indication encoding apparatus in this embodiment is better than the scheme in the protocol, and the advantage is more obvious when the AIDs are scattered.

In order to further save resources, in another embodiment of the present application, the apparatus further includes a first processing unit, where the first processing unit is configured to not split the partial virtual bitmap field when the DTIM count and at least one of the first byte counts do not satisfy the first predetermined condition.

In another embodiment of the present application, the apparatus further includes a second processing unit, where the second processing unit is configured to not split the partial virtual bitmap field when the number of the first STAs is less than 2. When the number of the first STA is less than 2, the first STA is not split, and resources are saved.

In order to make the traffic indication coding formats consistent under different conditions, in yet another embodiment of the present application, the first processing unit or the second processing unit includes a first processing module and a second processing module, where the first processing module is configured to mark the traffic indication bit as a fragmentation indication bit when the DTIM count is not 0, and the fragmentation indication bit has a value of 0; the second processing module is configured to add the ending identifier field after the bitmap control field when the DTIM count is 0.

In practical application, when the DTIM count is not 0, since the traffic indication bit in the bitmap control field is reserved and is used as the fragmentation indication bit, the fragmentation indication bit being 0 indicates that no partial virtual bitmap is split, only one partial virtual bitmap indicates a traffic buffering condition, if only zero or one STA has a buffered traffic at the AP, the splitting is not required, and the TIM element format is as shown in table 18. When the DTIM count is 0, since the traffic indication bit in the bitmap control field is not a reserved bit but needs to be used as a traffic indication field of the multicast/broadcast frame, additional information is needed to indicate whether fragmentation is performed, an end identification field may be added behind the bitmap control field, the TIM element format is shown in table 19, a fragmentation indication field may be added behind the bitmap control field, the fragmentation indication field indicates that a part of the virtual bitmap is not fragmented for the first symbol, and the TIM element format is shown in table 20.

Table 18 TIM element format for not splitting partial virtual bitmap when DTIM count is not 0

TIM element format for not splitting partial virtual bitmap when DTIM count of table 19 is 0

Table 20 shows another TIM element format without splitting a partial virtual bitmap when the DTIM count is 0

In order to make the value of the bitmap offset indicating the partial virtual bitmap larger, in a further embodiment of the present application, the apparatus further includes a determining unit and a third processing unit, where the determining unit is configured to determine whether the DTIM count is 0 when the number of the first STAs is less than 2; the third processing unit is configured to control the traffic indication bit to be combined with the bitmap offset bit to obtain a target bitmap offset when the DTIM count is not 0, where the target bitmap offset is used to represent a byte at which the partial virtual bitmap starts.

Specifically, when the bitmap offset is set to K, that is, the partial virtual bitmap is indicated to start from K × 2 bytes, which is denoted as N1, and N2 is the last byte number indicated by the partial virtual bitmap. That is, the traffic virtual bitmaps for workstations with AIDs of 1 to N1 × 8-1 and (N2 + 1) × 8 to 2007 are all 0. The length of the partial virtual bitmap field is 0-251 bytes, that is, the partial virtual bitmap field contains 2008 bits at most, the value of bit N (1 ≦ N ≦ 2007) in the bitmap indicates whether the STA with AID N has cache traffic at the AP, 1 represents that there is cache, and 0 represents that there is no cache. Bit 0 is a reserved field and is not allocated to a node to represent all multicast and broadcast. Since the indication partial virtual bitmap starts from K × 2 bytes, that is, the number of starting bytes of the partial virtual bitmap is always even, when the number of bytes of the AID of the STA to be indicated is odd, an indication byte number is wasted. In the above embodiment, for the TIM element whose DTIM count is not 0, since the traffic indication bit in the bitmap control field is reserved, it may also be used as a bitmap offset bit. That is, a total of 8 bits is used to indicate the bitmap offset, when the bitmap offset is set to K, that is, when the bitmap offset indicates that part of the virtual bitmap starts from K bytes, that is, when the number of bytes where the AID of the STA that needs to be indicated is located is odd, one indicated byte number is saved.

In practical applications, the above apparatus may be used when the number of the first STAs is greater than or equal to 2.

The encoding device of the flow indication map comprises a processor and a memory, wherein the acquisition unit, the splitting unit and the like are stored in the memory as program units, and the processor executes the program units stored in the memory to realize corresponding functions.

The processor comprises a kernel, and the kernel calls the corresponding program unit from the memory. The kernel can be set to one or more than one, and the problem of resource waste under the condition that AIDs of STAs needing indication in a part of virtual bitmaps are dispersed in the prior art is solved by adjusting kernel parameters.

The memory may include volatile memory in a computer readable medium, random Access Memory (RAM) and/or nonvolatile memory such as Read Only Memory (ROM) or flash memory (flash RAM), and the memory includes at least one memory chip.

The embodiment of the invention provides a computer-readable storage medium, which includes a stored program, wherein when the program runs, a device where the computer-readable storage medium is located is controlled to execute an encoding method of the flow indication map.

The embodiment of the invention provides a processor, which is used for running a program, wherein the program executes the coding method of the flow indication graph during running.

The embodiment of the invention provides equipment, which comprises a processor, a memory and a program which is stored on the memory and can run on the processor, wherein when the processor executes the program, at least the following steps are realized:

step S101, obtaining a DTIM count, the number of first STAs and a first AID corresponding to the first STAs, wherein the first STAs are the STAs with cache data at an AP;

step S102, splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs, and each first AID, so that each first AID has a corresponding start identifier field and an end identifier field, where the start identifier field and the end identifier field are used to represent a byte section of a byte position where each first AID is located.

The device herein may be a server, a PC, a PAD, a mobile phone, etc.

The present application further provides a computer program product adapted to perform a program of initializing at least the following method steps when executed on a data processing device:

The present application further provides an electronic device, including: one or more processors, memory, a display device, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs including encoding methods for performing any of the above-described flow indication maps.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static Random Access Memory (SRAM), dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), read Only Memory (ROM), electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), digital Versatile Disks (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium, which can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising one of 8230; \8230;" 8230; "does not exclude the presence of additional like elements in a process, method, article, or apparatus that comprises the element.

From the above description, it can be seen that the above-mentioned embodiments of the present application achieve the following technical effects:

1) In the method for encoding the flow indication map, firstly, a DTIM count, the number of first STAs and first AIDs corresponding to the first STAs are obtained, wherein the first STAs are STAs with cache data at APs; and then, splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs and each first AID, so that each first AID has a corresponding start identification field and an end identification field, and the start identification field and the end identification field are used for representing a byte section of a byte position where each first AID is located. According to the method, the AIDs of the STAs needing to be indicated are split into bytes in an interval near the bytes where the AIDs of the STAs needing to be indicated are located, and a plurality of partial virtual bitmaps are formed, so that the number of bytes can be saved, resources are saved, and the problem that resources are wasted under the condition that the AIDs of the STAs needing to be indicated in the partial virtual bitmaps in the prior art are scattered is solved.

2) In the encoding device of the traffic indication map, the obtaining unit obtains a DTIM count, the number of first STAs and a first AID corresponding to the first STA, where the first STA is an STA having cache data at an AP; and splitting the partial virtual bitmap field by the splitting unit according to the DTIM count, the number of the first STAs and each first AID, so that each first AID has a corresponding start identification field and an end identification field, and the start identification field and the end identification field are used for representing a byte interval of a byte position where each first AID is located. A large number of indication byte numbers can be wasted under the condition that AIDs of STAs needing to be indicated in the partial virtual bitmaps are scattered.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. An encoding method of a traffic indication map, the traffic indication map at least includes a DTIM count field, a bitmap control field and a partial virtual bitmap field, the bitmap control field includes a traffic indication bit and a bitmap offset bit, the partial virtual bitmap field includes at least one AID, and the method is characterized by comprising:

obtaining a DTIM count, the number of first STAs and first AIDs corresponding to the first STAs, wherein the first STAs are the STAs with cache data at an AP;

splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs and each first AID, so that each first AID has a corresponding start identification field and an end identification field, and the start identification field and the end identification field are used for representing a byte interval of a byte position where each first AID is located.

2. The method of claim 1, wherein the type of AID comprises the first AID and a second AID, wherein the STA corresponding to the second AID does not have data buffered in the AP, wherein the DTIM count comprises two cases of 0 and not 0, and wherein splitting the partial virtual bitmap field according to the DTIM count, the number of the first STAs, and the first AID comprises:

acquiring the number of bytes of the second AID between any two adjacent first AIDs to obtain at least one first number of bytes under the condition that the number of the first STAs is greater than or equal to 2;

splitting the partial virtual bitmap field if the DTIM count and at least one of the first number of bytes satisfy a first predetermined condition, the first predetermined condition including: the DTIM count is 0, the first byte number of each first byte is greater than 2, the DTIM count is not 0, the first byte number is greater than 3, the DTIM count is not 0, the Nth first byte number is greater than 2, the first byte number is the first byte number between the first two adjacent first AIDs, N is a positive integer greater than or equal to 2, and the Nth first byte number is the first byte number between any two adjacent first AIDs after the second first AID.

3. The method of claim 2, wherein splitting the partial virtual bitmap field in the event that the DTIM count and at least one of the first number of bytes satisfy a first predetermined condition comprises:

under the first predetermined condition that the DTIM count is not 0 and the first number of bytes is greater than 3, or the DTIM count is not 0 and the nth number of bytes is greater than 2, marking the traffic indication bit as a fragmentation indication bit, where the fragmentation indication bit has a value of 1, and adding the end identification field before the first AID, and adding the start identification field and the end identification field before each first AID after the first AID.

4. The method of claim 2, wherein splitting the partial virtual bitmap field in the event that the DTIM count and at least one of the first number of bytes satisfy a first predetermined condition comprises:

and when the first predetermined condition is that the DTIM count is 0 and the number of first bytes is greater than 2, adding the end identifier field before a first AID, and adding the start identifier field and the end identifier field before each first AID after the first AID.

5. The method of claim 2, further comprising:

not splitting the partial virtual bitmap field if the DTIM count and at least one of the first number of bytes do not satisfy the first predetermined condition.

6. The method of claim 2, further comprising:

and under the condition that the number of the first STAs is less than 2, the partial virtual bitmap field is not split.

7. The method of claim 5 or 6, wherein not splitting the partial virtual bitmap field comprises:

under the condition that the DTIM count is not 0, marking the flow indicating bit as a fragment indicating bit, wherein the value of the fragment indicating bit is 0;

and under the condition that the DTIM count is 0, adding the ending identification field after the bitmap control field.

8. The method of claim 2, further comprising:

determining whether the DTIM count is 0 if the number of the first STAs is less than 2;

and under the condition that the DTIM count is not 0, controlling the flow indication bit to be combined with the bitmap offset bit to obtain a target bitmap offset, wherein the target bitmap offset is used for representing the starting bytes of the partial virtual bitmap.

9. An encoding device of a traffic indication map, the traffic indication map at least includes a DTIM count field, a bitmap control field, and a partial virtual bitmap field, the bitmap control field includes a traffic indication bit and a bitmap offset bit, the partial virtual bitmap field includes at least one AID, and the encoding device is characterized by comprising:

an obtaining unit, configured to obtain a DTIM count, a number of first STAs, and a first AID corresponding to the first STA, where the first STA is an STA having cached data at an AP;

and a splitting unit, configured to split the partial virtual bitmap field according to the DTIM count, the number of the first STAs, and the first AID, so that the first AID has a start identification field and an end identification field corresponding to the first AID, and the start identification field and the end identification field are used to represent byte positions where the first AID is located.

10. A computer-readable storage medium, comprising a stored program, wherein the program, when executed, controls an apparatus in which the computer-readable storage medium is located to perform the method for encoding the traffic indication map according to any one of claims 1 to 8.

11. A processor, characterized in that the processor is configured to execute a program, wherein the program executes the method for encoding a traffic indication map according to any one of claims 1 to 8.

12. An electronic device, comprising: one or more processors, memory, a display device, and one or more programs, wherein the one or more programs are stored in the memory and configured to be executed by the one or more processors, the one or more programs comprising code for performing the method of encoding the flow indication map of any of claims 1-8.