tag:blogger.com,1999:blog-35417538.post476540544680197118..comments2007-04-02T11:07:20.066+08:00Paul Mahnoreply@blogger.comBlogger4125tag:blogger.com,1999:blog-35417538.post-84219149704376552622007-04-02T11:07:00.000+08:002007-04-02T11:07:00.000+08:00Hi Anonymous, you did not list your email, so I am not able to revert to you directly. Please post your questions at www.techatplay.com.Paul Mahhttp://www.blogger.com/profile/03703424266447233950noreply@blogger.comtag:blogger.com,1999:blog-35417538.post-63372235668490748892007-03-27T22:43:00.000+08:002007-03-27T22:43:00.000+08:00Nice page you have here!<BR/><BR/>I just want to verify one thing.<BR/><BR/>By reading your article I get the impression that the heartbeat only serves to verify that a connection isn't lost due to some unexpected circumstances.<BR/><BR/>I believe that the heartbeat is also necessary because the connection will always be lost after a fixed time due to a time-out value defined by network settings.<BR/><BR/>Am I right?<BR/><BR/>I also wonder why the changes (new mail for example) can't be sent down the open TCP connection as soon as they occur. Why must the MS issue the sync?Anonymousnoreply@blogger.comtag:blogger.com,1999:blog-35417538.post-49295279224360451482006-10-19T13:48:00.000+08:002006-10-19T13:48:00.000+08:00Yes, you are right in that sense. For (2), it really is the limitation of GPRS itself. The trade-off is that since Direct Push essentially works on standard TCP/IP technology, you are not held hostage as to whether your telco is Blackberry-enabled and where I live (Singapore), you can opt for the cheaper pure data plans and not have to pay the higher-priced Blackberry subscription.<br /><br />But overall, I find that the data useage is quite acceptable. Personally, my traffic is at about 5MB a month when set to "Manually" for weekdays 9am-6pm, and "When new items arrive" for the rest of the time. I receive average 15 mails during the non-manual setting period - though I only download the first 1KB most of the time. I don't use GPRS for any other activity.Paul Mahhttp://www.blogger.com/profile/03703424266447233950noreply@blogger.comtag:blogger.com,1999:blog-35417538.post-11249398219361385322006-10-18T23:23:00.000+08:002006-10-18T23:23:00.000+08:00Note that, as I understnad it, the high bandwidth overhead of Direct Push is in part due to the way the heartbeat works and the fact that it will send a new package every time:<br /><br />1) You switch on the device<br />2) You end a phone call (unless you are on 3G or better)<br />3) You lose data reception and regain it<br />4) A change occurs and so a 'sync' takes place (e.g. new email(s) arrives)<br />5) Timeout period for the heartbeat is reached<br /><br />Add this up over a month and most users are seeing >10MB a month of traffic however well 'tweaked' their timeout settings are.Anonymousnoreply@blogger.com