[android] Tablets not able to synchronise time in school

[spadam]

We have a few Android tablets in our school which we are testing with a view to maybe buying more if they prove useful. Amongst those that we have are 4 Scroll Extreme tablets (Android 4.0.4) which we bought because they were cheap to be used as shared devices in classrooms. The plan is that these tablets will never be taken out of school.

 

The tablets connect to the internet via our Smartcache proxy. The problem is that the tablets will not synchronise time from the network while in school despite having selected this in the Settings. This means that if left off for a few days the tablets revert back to default time and have to be manually reset before they will connect to the Play store. I took one home to test it and the time synchronised almost immediately so there is something about our school network that is causing the issue. Other tablets we have which run Android 4.4.2 synchronise the time ok.

 

There is nothing showing up as filtered for the tablet on our Smartcache logs... I can see that it periodically connects to a few https://android.clients.google.com/..... urls and I am guessing that these are how it normally updates the time but am not really sure. I have limited knowledge of networking, proxy servers, firewalls and don't really know where else to look to try and work out if this can be resolved for these devices. Has anyone else experienced anything similar or know what else I can try to resolve this?

[localzuk]

Android does not have 100% support for proxies, so it is quite probable that it is trying to do it using a non-web based port and is therefore blocked by your firewall/router.

[spadam]

This is what I was thinking was most likely, I just don't understand why the 4.4.2 devices sync ok but these ones don't unless the way they do it changed between versions....

 

The firewall/router are managed by RM so I have no access. RM say that if they investigate this issue any further and it turns out to be a problem with the devices rather than the network then they will charge us for the engineers time so I am really reluctant to ask them to look into it but at the same time I don't see how else to get it resolved.