LTE: Define Location Service (LCS) and how it works?

Question

In PDCP layer, there is functionality of timer based discard. Can anyone please elaborate on this functionality of PDCP layer.

Answer 1

To better define it this one be the best link
http://tech.queryhome.com/42618/location-based-services-lcs-architecture-for-lte-eps

and how does it works ?
In the LCS architecture, an Evolved SMLC is directly attached to the MME. The objectives of this evolution is to support location of an IMS emergency call, avoid impacts to a location session due to an inter-eNodeB handover, make use of an Evolved and support Mobile originated location request (MO-LR) and mobile terminated location request MT-LR services.

Release 9 LCS solution introduces new interfaces in the EPC:

SLg between the GMLC and the MME
SLs between the E-SMLC and the MME
Diameter-based SLh between the HSS and the HGMLC