Friday 12 September 2008

eHRPD: Stopgap between EV-DO and LTE

Interesting article from TMCnet.

As LTE is picking up steam, more and more operators opting for this technology. It is but natural that some CDMA2000 operators would like to joing the camp as well. Since there is no clear evolution path available from CDMA2000 to LTE, a soft option is required so that there is no immediate need to change the complete infrastructure and in case of any problems suffer.

The transition for CDMA operators from High Rate Packet Data (HRPD) to LTE will be over a period of several years, as is the case still with the transition from 1xRTT to HRPD. As a result, mobile operators must look for a migration path that will enhance their existing HRPD networks, while addressing LTE deployment requirements and will not require a ‘forklift’ upgrade.

The choice of migration path depends on many factors including radio access strategy, network resource strategy, services enabled, timing and cost. A key goal of LTE is to enhance service provisioning while simplifying interworking with non-3GPP mobile networks. This is essential for CDMA operators that have chosen to migrate to LTE.

Evolved HRPD is a method that allows the mobile operator to upgrade their existing HRPD packet core network using elements of the SAE/EPC architecture. Additionally, eHRPD is a more evolutionary path to LTE while also allowing for seamless service mobility — including seamless hand-offs — between the eHRPD and LTE networks.

One of the main advantages of eHRPD is the ability to provide seamless service mobility between HRPD and LTE access networks with a single mobility management protocol. Moreover, with eHRPD, the operator can leverage the benefit of optimized handover – no dropped sessions and reduced handover latency — between LTE and eHRPD. The benefit of seamless and optimized mobility for data is highly dependant on the mobile operator business model for adding new services. As new applications emerge, the requirement for seamless service mobility becomes greater. Since SAE is an all-IP network infrastructure, the network will quickly move to mobile VoIP for voice. Moreover, with the introduction of eHRPD, the operator can leverage the benefit of optimized intra eHRPD handover when the user crosses the HSGW boundaries. This capability does not exist in current HRPD systems.

You can read the complete article here.


Kat said...

Thanks for the concise and useful post on eHRPD. This blog has been one of my resources when I needed something quick, accurate, to the point and precise on HSPA, HSPA+ features and LTE.

RK said...

You said that with introduction of ehrpd the UE is able to perform optimized handover when crossing HSGW boundaries and " this feature is not there in HRPD" . Could you elaborate the last line a little more. how is it that optimized handovers are not supported in HRPD.?