in a method for distributing a mobile broadcast service according to an embodiment of the present invention , header information is added into broadcast service contents , the header information includes integrality information and version information of a service packet . the service packet contains the broadcast service contents . the service packet is classified into integral service packet or update service packet in accordance with the integrality information . the version information reflects the version of a service packet . the service packet is distributed to a user terminal ; the user terminal may update or accept its own service data by using the service packet in accordance with the integrality information and version information of the service packet . in an embodiment of the present invention , the content information of an update service packet may be divided into three portions including contents to be added , contents to be changed or contents to be deleted . in actual applications , the content information of an update service packet may be divided into more portions , for example , the contents to be changed may be configured into multiple levels so that different levels of the contents to be changed may be changed differently . in one embodiment , the method according to the embodiments of the present invention may be implemented in several ways . one way is to distribute a service packet to a user terminal in accordance with the integrality of the service packet through the following steps : first , it is determined in accordance with the integrality information of the service packet . if the service packet is an integral service packet , the integral service packet of a new version is compared with the integral service packet of a current version . if the new version is higher than the current version , the integral service packet of the current version is replaced with the integral service packet of the new version , and then the integral service packet of the new version is distributed to the user terminal . otherwise the integral service packet of the new version may be discarded . if the service packet is an update service packet , similarly the update service packet of the new version is compared with the update service packet of the current version . if the new version is higher than the current version , the update service packet of the current version is replaced with the update service packet of the new version , and the update service packet of the new version is distributed to the user terminal . otherwise the update service packet of the new version may be discarded . secondly , a user terminal that has received the service packet may update or accept its own service data through the following procedures : the user terminal determines in accordance with the integrality information of the received service packet . if the received service packet is an integral service packet , the user terminal overwrites the current service packet stored locally with the integral service packet ; otherwise the user terminal compares the version of the received service packet with the version of the current service packet stored locally . if the version of the received service packet is higher than the version of the service packet stored locally and the version difference is equal to a predefined number of levels , the user terminal updates the service packet stored locally with the received service packet . if the version of the received service packet is higher than the version of the service packet stored locally and the version difference is greater than the predefined number of levels , the user terminal sends an integral service packet request to the network side through an interactive channel carrying the version information of the current service packet stored locally in the user terminal , requesting for the latest integral service packet . if the version of the received service packet is lower than or equal to the version of the service packet stored locally , the user terminal may discard the received service packet . usually , there are different ways for setting or counting the version , and the number of levels of the version difference may be set as required . in this embodiment , the version is counted with natural numbers , for example , version 1 , version 2 , . . . , version n , etc . therefore , the number of levels of the version difference is 1 in this embodiment . furthermore , the user terminal may update the service packet stored locally with the received service packet in various different ways , for example : for contents to be added , the user terminal may insert the contents to be added directly to the service packet stored locally and then update the version of the service packet into the version of the received service packet . for contents to be changed , the user terminal may change corresponding contents in the service packet stored locally in accordance with the contents to be changed and then update the version of the service packet into the version of the received service packet . for contents to be deleted , the user terminal may delete the corresponding contents from the service packet stored locally and then update the version of the service packet stored locally into the version of the received service packet . hereinafter more embodiments of the present invention will be detailed with reference to the accompanying drawings . fig1 is the block diagram of a system according to an embodiment of the present invention . the system as shown in fig1 includes a broadcast service distributor 1 , an interactive service unit 2 , a broadcast service unit 3 , a user terminal 4 , and a determining and selecting unit 5 . the broadcast service distributor 1 is adapted to add header information into broadcast service contents . the header information includes integrality information and version information of the service packet containing the broadcast service contents , the service packet is classified into an integral service packet or an update service packet in accordance with the integrality information , and the version information reflects the version of the service packet . furthermore , the broadcast service distributor 1 is also adapted to distribute an integral service packet and an update service packet to the interactive service unit 2 and broadcast service unit 3 . the interactive service unit 2 is adapted to receive an integral service packet and distribute the corresponding integral service packet to the user terminal 4 . the broadcast service unit 3 is adapted to receive an update service packet and distribute the corresponding update service packet to the user terminal 4 . the determining and selecting unit 5 is adapted to determine the service packet containing the broadcast service contents distributed by the broadcast service distributor 1 in accordance with the integrality information , and enable the broadcast service distributor 1 to distribute the service packet to the interactive service unit 2 or broadcast service unit 3 accordingly , and thereby enable the interactive service unit 2 and broadcast service unit 3 to distribute the corresponding service packet to the user terminal 4 . in this embodiment , the determining and selecting unit 5 is provided with a storage module 51 which saves the version information of the service packet stored in interactive service unit 2 or the broadcast service unit 3 , as shown in fig1 . fig2 shows a basic control flow of the system as shown in fig1 ; and fig3 is a control flow diagram of the embodiment as shown in fig2 . as shown in fig1 and fig2 : 1 ) the broadcast service distributor 1 adds header information into the broadcast service contents to be distributed . the header information includes at least integrality information and version information of the service packet containing the broadcast service contents , the service packet is classified into an integral service packet or an update service packet in accordance with the integrality information , and the version information reflects the version of the service packet . 2 ) the determining and selecting unit 5 determines the integrality information and version information of the service packet as follows : 21 ) if the service packet is an integral service packet and the version of the service packet is higher than the version of the service packet stored in the interactive service unit 2 , the service packet will be transmitted to the interactive service unit 2 ; 22 ) if the service packet is an update service packet and the version of the service packet is higher than the version of the service packet stored in the broadcast service unit 3 , the service packet will be transmitted to the broadcast service unit 3 . 3 ) the interactive service unit 2 or the broadcast service unit 3 distributes the service packet to the user terminal 4 . 4 ) the user terminal 4 updates or processes the service packet in accordance with the information contained in the service packet . when the condition of integrality information and the condition of version information are met at the same time , these conditions constitute the sufficient condition for distributing the service packet to the interactive service unit or broadcast service unit . in other words , the interactive service unit 2 or broadcast service unit 3 will distribute the service packet to the user terminal 4 . 1 . the broadcast service distributor 1 adds header information into the service packet containing the broadcast service contents to be distributed , the header information includes integrality information and version information . as shown in fig4 , in the integral service packet , the service contents are divided into n segments based on the principle of independence and self - containing . each segment has a specific id and contents , each id is a global parameter and corresponds to the contents of a unique segment exclusively . the integrality information f / p is a boolean variable . if f / p is true , it indicates that the service packet is an integral service , and if f / p is false , it indicates that the service packet is an update service packet . the version field is the unique id of the version of the service packet and is an integer variable . the version of the service packet depends on the time when the service packet is generated . the higher the version is , the greater the version value will be ; on the other hand , the lower the version is , the smaller the version value will be . as shown in fig5 , in the update service packet , the header information portion “ info of header ” is identical with that in the integral service packet . the content information includes three portions : contents to be added ( new contents ), contents to be changed ( change contents ), contents to be deleted ( delete contents ). these three portions contain the field identifications , the corresponding identification numbers ids , and the contents of the segments corresponding to the ids . the field identifications identify the contents to be added , contents to be changed , contents to be deleted respectively . 2 . the determining and selecting unit 5 processes as follows in accordance with the integrality information of the service packet : 21 . if the integrality information indicates that the service packet is an integral service packet , the determining and selecting unit 5 will compare the version of the integral service packet with the version of the current integral service packet stored in the interactive service unit 2 ( in the embodiment of the present invention , the version information of the current integral service packet stored in the interactive service unit 2 is stored in the storage module 51 ), and execute the following process : 211 . if the version of the integral service packet is higher than the version of the current integral service packet stored in the interactive service unit 2 , the determining and selecting unit 5 distributes the service packet to the interactive service unit 2 , and enables the current integral service packet stored in the interactive service unit 2 to be overwritten with the service packet , and updates the information stored in the storage module 51 accordingly ; 212 . if the version of the service packet is lower than or equal to the version of the current integral service packet stored in the interactive service unit 2 , the determining and selecting unit 5 discards the service packet . 22 . if the integrality information indicates that the service packet is an update service packet , the determining and selecting unit 5 will compare the version of the service packet with the version of the current update service packet stored in the broadcast service unit 3 ( in the embodiment of the present invention , the version information of the current update service packet stored in the broadcast service unit 3 is stored in the storage module 51 ), and execute the following process : 221 . if the version of the service packet is higher than the version of the current update service packet stored in the broadcast service unit 3 , the determining and selecting unit 5 distributes the service packet to the broadcast service unit 3 , and enables the current update service packet stored in the broadcast service unit 3 to be overwritten with the service packet , and updates the information stored in the storage module 51 accordingly ; 222 . if the version of the service packet is lower than or equal to the version of the current integral service packet stored in the interactive service unit 2 , the determining and selecting unit 5 discards the service packet . 3 . the interactive service unit 2 or the broadcast service unit 3 distributes the service packet to the user terminal 4 . for an update service packet , if any error occurs during the distribution procedure and thus the user terminal 4 can not receive the current update service packet , the user terminal 4 will send an integral service packet request to the interactive service unit 2 through the interactive channel requesting for the latest integral service packet . the interactive service unit 2 will distribute the requested integral service packet to the user terminal 4 . 4 . the user terminal 4 processes the service packet as follows in accordance with the header information in the service packet : 41 . if the integrality information indicates that the service packet is an integral service packet , the user terminal 4 will overwrite the current service packet stored locally with this integral service packet directly . 42 . if the integrality information indicates that the service packet is an update service packet , the user terminal 4 will determine the version of the update service packet in accordance with the header information and processes as follows : 421 . if the version of the update service packet is lower than or equal to the version of the current service packet stored locally in the user terminal 4 , the user terminal discards the update service packet ; 422 . if the version of the update service packet is higher than the version of the current service packet stored locally in the user terminal 4 , the user terminal executes the following process : 4221 . if the version of the update service packet is higher than the version of the current service packet stored in the user terminal by only one level of version , the user terminal 4 will query in the contents of the service packet for the field identification identifying contents to be added , contents to be changed , or contents to be deleted and the corresponding identification number id , and updates the current service packet stored locally with the update service packet as follows : 42211 . for contents to be added , the user terminal directly inserts the contents corresponding to the id in the update service packet into the current service packet stored locally , and updates the version information of the current service packet stored locally into the version of the update service packet ; 42212 . for contents to be changed , the user terminal changes the contents corresponding to the id in the current service packet stored locally into the contents to be changed in the update service packet , and updates the version information of the current service packet stored locally into the version of the update service packet ; 42213 . for contents to be deleted , the user terminal deletes the contents corresponding to the id from the current service packet stored locally , and updates the version information of the current service packet stored locally into the version of the update service packet . 4222 . if the version of the service packet is higher than the version of the current service packet stored in the user terminal by two or more levels of version , the user terminal 4 will send an integral service packet request to the interactive service unit 2 through the interactive channel requesting for the latest integral service packet . the interactive service unit 2 will distribute the requested integral service packet to the user terminal 4 . in an embodiment of the present invention , the determining and selecting unit 5 may obtain the version information of the service packet stored in the interactive service unit 2 or the broadcast service unit 3 through a direct information interaction with the interactive service unit 2 or the broadcast service unit 3 . in this case , the storage module 51 may be omitted . this alteration may be recognized by a person of ordinary skill readily , and therefore will not be repeated here . in an embodiment of the present invention , the determining and selecting unit 5 may be integrated in the broadcast service distributor 1 . this alteration may be recognized by a person of ordinary skill readily , and therefore will not be repeated here .