Efficient content delivery over wireless networks using guaranteed prefetching

Abstract

A method for content delivery includes selecting one or more time intervals. During each time interval among the selected time intervals, given content is prefetched from a content source to a communication terminal using a guaranteed prefetching mode, by continuously tracking the given content on the content source, so as to detect changes to the given content as they occur during the selected time interval, and maintaining the communication terminal continuously synchronized with the content source with respect to the given content, throughout the selected time interval, notwithstanding the changes that occur during the selected time interval, by continuously prefetching at least part of the given content from the content source to the communication terminal. Outside of the one or more selected time intervals, the given content is prefetched using a best-effort prefetching mode, by tracking the given content less frequently than the guaranteed prefetching mode.

1 - 39 . (canceled) 
     
     
         40 . A method for content delivery to a communication terminal, the method comprising:
 selecting one or more content items on a content source;   assigning the selected content items to be handled by a guaranteed prefetching mode in which (i) the selected content items are continuously tracked on the content source, so as to detect changes to the content items as they occur, and (ii) the communication terminal is continuously maintained synchronized with the content source with respect to the selected content items, notwithstanding the changes that occur, by continuously prefetching at least part of the selected content items from the content source to the communication terminal;   prefetching the selected content items from the content source to the communication terminal using the guaranteed prefetching mode; and   visually marking the selected content items with visual marks, which indicate to a user of the communication terminal that the selected content items have been assigned to be handled using the guaranteed prefetching mode.   
     
     
         41 . The method according to  claim 40 , and comprising prefetching one or more other content items, which are not assigned to the guaranteed prefetching mode, using a best-effort prefetching mode, by tracking the one or more other content items less frequently than in the guaranteed prefetching mode. 
     
     
         42 . The method according to  claim 40 , wherein selecting the one or more content items comprises:
 evaluating, for at least some of the content items on the content source, respective visibility metrics that are indicative of one or more of (i) respective times and (ii) respective amounts of user actions, needed to make the content items visible to the user; and   selecting the content items based on the visibility metrics.   
     
     
         43 . The method according to  claim 40 , wherein selecting the one or more content items comprises (i) selecting a first content item that is visible without scrolling when presented on the communication terminal, and (ii) not selecting a second content item that requires scrolling to be visible. 
     
     
         44 . The method according to  claim 40 , wherein selecting the one or more content items comprises (i) selecting a first content item that is available on a landing page of an application, and (ii) not selecting a second content item that is not available on the landing page. 
     
     
         45 . The method according to  claim 40 , wherein selecting the one or more content items comprises (i) selecting a first content item that is accessible from a current display of the communication terminal, and (ii) not selecting a second content item that is not accessible from the current display. 
     
     
         46 . The method according to  claim 40 , wherein selecting the one or more content items comprises (i) selecting a first content item that changes at a rate that is lower than a predefined threshold, and (ii) not selecting a second content item that changes at a rate that is above the predefined threshold. 
     
     
         47 . The method according to  claim 40 , wherein selecting the one or more content items comprises (i) selecting a first content item having a level of security that is above a predefined threshold, and (ii) not selecting a second content item having a level of security that is below the predefined threshold. 
     
     
         48 . A method for content delivery to a communication terminal, the method comprising:
 evaluating a condition depending one or more of (i) a movement of the communication terminal, (ii) a velocity of the communication terminal, (iii) exposure of the communication terminal to light, (iv) a screen-lock status of the communication terminal, (v) a battery level of the communication terminal, (vi) a charging status of the communication terminal, (vii) a quality of a network connection of the communication terminal, and (viii) a type of the network connection;   when the condition is met, prefetching content from a content source to the communication terminal using a guaranteed prefetching mode in which (i) content items are continuously tracked on the content source, so as to detect changes to the content items as they occur, and (ii) the communication terminal is continuously maintained synchronized with the content source with respect to the content items, notwithstanding the changes that occur, by continuously prefetching at least part of the content items from the content source to the communication terminal; and   when the condition is not met, prefetching content from the content source to the communication terminal using a prefetching mode other than the guaranteed prefetching mode.   
     
     
         49 . A content delivery system, comprising:
 an interface for communicating with a content source and with a communication terminal; and   one or more processors, which are configured to:
 select one or more content items on a content source; 
 assign the selected content items to be handled by a guaranteed prefetching mode in which (i) the selected content items are continuously tracked on the content source, so as to detect changes to the content items as they occur, and (ii) the communication terminal is continuously maintained synchronized with the content source with respect to the selected content items, notwithstanding the changes that occur, by continuously prefetching at least part of the selected content items from the content source to the communication terminal; 
 prefetch the selected content items from the content source to the communication terminal using the guaranteed prefetching mode; and 
 visually mark the selected content items with visual marks, which indicate to a user of the communication terminal that the selected content items have been assigned to be handled using the guaranteed prefetching mode. 
   
     
     
         50 . The system according to  claim 49 , wherein the one or more processors are configured to prefetch one or more other content items, which are not assigned to the guaranteed prefetching mode, using a best-effort prefetching mode, by tracking the one or more other content items less frequently than in the guaranteed prefetching mode. 
     
     
         51 . The system according to  claim 49 , wherein the one or more processors are configured to:
 evaluate, for at least some of the content items on the content source, respective visibility metrics that are indicative of one or more of (i) respective times and (ii) respective amounts of user actions, needed to make the content items visible to the user; and   select the content items based on the visibility metrics.   
     
     
         52 . The system according to  claim 49 , wherein the one or more processors are configured to (i) select a first content item that is visible without scrolling when presented on the communication terminal, and (ii) not select a second content item that requires scrolling to be visible. 
     
     
         53 . The system according to  claim 49 , wherein the one or more processors are configured to (i) select a first content item that is available on a landing page of an application, and (ii) not select a second content item that is not available on the landing page. 
     
     
         54 . The system according to  claim 49 , wherein the one or more processors are configured to (i) select a first content item that is accessible from a current display of the communication terminal, and (ii) not select a second content item that is not accessible from the current display. 
     
     
         55 . The system according to  claim 49 , wherein the one or more processors are configured to (i) select a first content item that changes at a rate that is lower than a predefined threshold, and (ii) not select a second content item that changes at a rate that is above the predefined threshold. 
     
     
         56 . The system according to  claim 49 , wherein the one or more processors are configured to (i) select a first content item having a level of security that is above a predefined threshold, and (ii) not select a second content item having a level of security that is below the predefined threshold. 
     
     
         57 . A content delivery system, comprising:
 an interface for communicating with a content source and with a communication terminal; and   one or more processors, which are configured to:
 evaluate a condition depending one or more of (i) a movement of the communication terminal, (ii) a velocity of the communication terminal, (iii) exposure of the communication terminal to light, (iv) a screen-lock status of the communication terminal, (v) a battery level of the communication terminal, (vi) a charging status of the communication terminal, (vii) a quality of a network connection of the communication terminal, and (viii) a type of the network connection; 
 when the condition is met, prefetch content from a content source to the communication terminal using a guaranteed prefetching mode in which (i) content items are continuously tracked on the content source, so as to detect changes to the content items as they occur, and (ii) the communication terminal is continuously maintained synchronized with the content source with respect to the content items, notwithstanding the changes that occur, by continuously prefetching at least part of the content items from the content source to the communication terminal; and 
 when the condition is not met, prefetch content from the content source to the communication terminal using a prefetching mode other than the guaranteed prefetching mode.