OX EMail Push Introduction

Introduction to EMail Push in Open-Xchange

Abstract

In combination with OXtender_for_Business_Mobility and OXtender_2_for_Microsoft_Outlook a working mail push is very important. It is important to know, that this is a combined requirement to the mail server and the Open-Xchange server to make that happen. Both of the listed OXtenders are accessing Open-Xchange via the USM interface (Universal Synchronization Module, which ist the package open-xchange-usm).

Mail Push with OXtender_for_Business_Mobility

In addition to an externally triggered mail push, in internal mail poll initiated by the usm module is executed.

This is, how this polling can be influenced via /opt/open-xchange/etc/groupware/usm.properties:

1. com.openexchange.usm.session.sync.email_pull_delay=50%
2. com.openexchange.usm.session.sync.email_pull_min_delay=60000

These values are the default values.

1. defines, when an internal poll should be triggered while waiting for the client. This can be done as an absolute value (in milliseconds) or as a percentage value based on the waiting time as been specified by by the client per Active Sync Protocol (EAS). In the EAS protocol, the client specifies this time dynamically, usually between 30 seconds and 30 minutes. If an absolute time is specified here and the time set by the client is smaller, a mail poll is initiated at the end of the waiting time if not prevented by the setting of (2).

2. defines an additional minimum waiting time, which is enforced to be followed, before an internal poll is executed. Is the value as specified by the EAS client/protocol smaller than this value, no poll will be executed. If 2. is set to a negative value, the internal mail polling of USM will be completely disabled.

Examples

(A)

com.openexchange.usm.session.sync.email_pull_delay=50%
com.openexchange.usm.session.sync.email_pull_min_delay=-1

Es wird kein internes Mail-Polling durch das USM durchgeführt.

B

com.openexchange.usm.session.sync.email_pull_delay=50%
com.openexchange.usm.session.sync.email_pull_min_delay=60000

Wartezeit des Clients: 30 Sekunden -> kein Mail-Polling 90 Sekunden -> Mail-Polling nach 60 Sekunden (!) 180 Sekunden -> Mail-Polling nach 90 Sekunden 1800 Sekunden -> Mail-Polling nach 900 Sekunden

C

com.openexchange.usm.session.sync.email_pull_delay=120000 com.openexchange.usm.session.sync.email_pull_min_delay=60000

Wartezeit des Clients: 30 Sekunden -> kein Mail-Polling 90 Sekunden -> Mail-Polling nach 90 Sekunden (!) 180 Sekunden -> Mail-Polling nach 120 Sekunden 1800 Sekunden -> Mail-Polling nach 120 Sekunden

D

com.openexchange.usm.session.sync.email_pull_delay=60000 com.openexchange.usm.session.sync.email_pull_min_delay=120000

Wartezeit des Clients: 30 Sekunden -> kein Mail-Polling 90 Sekunden -> kein Mail-Polling (!) 180 Sekunden -> Mail-Polling nach 120 Sekunden 1800 Sekunden -> Mail-Polling nach 120 Sekunden

Beispiel (D) ist nicht sehr sinnvoll, es soll vor allem aufzeigen, dass Property (2) eine höhere Priorität hat als Property (1).

Das Default-Verhalten ist damit:

Wartezeit X des Clients/Protokolls (in EAS: Ping):

       X < 60 s   -> kein interner Mail-Poll

60 s <= X <= 120 s -> interner Mail-Poll nach 60 s 120 s < X -> interner Mail-Poll nach X/2 s