| dc.description.abstract | The 3GPP Long Term Evolution (LTE) is considered as a dominant future cellular wireless
technology in terms of performance and user experience. With technological advancement of the
wireless networks, dependencies and business impact of the mobile network services have
increased phenomenally. It is, therefore, crucial to address the issues regarding network
infrastructure or service failure. In this thesis, a self-healing solution is presented for the LTE
Evolved Packet Core (EPC) with a view to maintaining service continuity in the event of core
network elements - the MME and S-GW failures. The core network element failures have
significant impact on a larger number of subscribers in comparison to the access network element
failures. In the proposed self-healing scheme, the restoration mechanisms and associate failover
recovery procedures with regards to service survivability are described in details from the LTE
network and protocol perspective.
This thesis studies two different self-healing approaches - the centralized active-backup and
distributed active-active and conducts simulation for each approach in various failure scenarios.
The performances of each of these scenarios are evaluated in terms of service restoration time,
throughput, EPS (Evolved Packet System) bearer delay etc. The results show that the proposed
self-healing system can ensure service continuity at a certain level if resources are properly
provisioned. And in terms of restoration delay, in general, the active-backup configuration
performs better than the active-active configuration.
The thesis presents analytical and simulation methods to estimate signaling message overhead at
the LTE EPC that arises due to the recovery process. It also analyzes the bandwidth requirements
of the signaling traffic that is incurred by the other operational procedures of the self-healing
scheme and their ramification to the LTE core network. | en |
