From 7671f4d091eb6c56ce38c7545450a6c171c5364c Mon Sep 17 00:00:00 2001 From: Mika Liljeberg Date: Mon, 25 Oct 2010 16:28:06 +0300 Subject: [PATCH] radio settings: document FastDormancy property --- doc/radio-settings-api.txt | 57 ++++++++++++++++++++++++++------------ 1 file changed, 40 insertions(+), 17 deletions(-) diff --git a/doc/radio-settings-api.txt b/doc/radio-settings-api.txt index f1b91ad9..00eca546 100644 --- a/doc/radio-settings-api.txt +++ b/doc/radio-settings-api.txt @@ -44,22 +44,45 @@ Properties string TechnologyPreference [read-write] boolean FastDormancy [read-write, optional] - This property will enable or disable fast - dormancy. Fast dormancy refers to UE initiated - release of radio resources quickly after a - burst of data transfer has ended. Normally, + This property will enable or disable the fast + dormancy feature in the modem. Fast dormancy + refers to a modem feature that allows the + modem to quickly release radio resources after + a burst of data transfer has ended. Normally, radio resources are released by the network - after a timeout configured by the network - operator. Fast dormancy allows the modem to - release radio resources more quickly. - Typically, fast dormancy would be enabled if - no data transfer is predicted to occur in the - near future, for instance, when the end user - is not actively using the device. This is a - major power-saving feature for mobile devices, - but can be ignored for USB sticks or PCI - devices. + after a timeout configured by the network. + Fast dormancy allows the modem to release the + radio resources more quickly. - If the modem does not support such a feature - the property should never be exposed to the - user. + Fast dormancy is a major power-saving feature + for mobile devices. Typically, fast dormancy + would be enabled when the device is not being + interactively used by a human user and only + networking applications with keep-alive + traffic are active (e.g. mail client or a + presence application). In this case it is + desirable to release radio resources quickly + after a keep-alive transaction has ended, + since typically no network traffic will occur + until the next keep-alive transaction. Fast + dormancy should not be enabled during + interactive use because the release and setup + of radio resources introduces perceivable + delay for the end user. + + The fast dormancy implementation in the modem + is vendor specific. The implementation should + try to release radio resources more quickly, + when the situation allows it, but should also + take care not to increase the signalling load + on the cellular network by releasing and + re-establishing radio resources too often. The + modem should adjust its behaviour to the 3GPP + release supported by the network and the + parameters set by the operator. + + Fast dormancy can be ignored for externally + powered modems such as USB sticks or PCI + devices. If the modem does not support such a + feature the property should never be exposed + to the user.