Target Network Selection and Network Assisted Roaming for Heterogeneous Access Networks. Jouni Korhonen / 30-Sep-2005

Transcription

1 Target Network Selection and Network Assisted Roaming for Heterogeneous Access Networks Jouni Korhonen / 30-Sep-2005

2 Topics Background General requirements Open issues Topics for Work/Research Thoughts and concerns Example

3 Background Background in WLAN roaming work An operator may have hundreds of roaming partners Mobile nodes are surrounded by multiple possible targer networks Currently no tools to manage roaming and handovers on IP data oriented devices from network side Currently there is no standard way of managing roaming and handover policies on mobile terminals Cellulars have OTA & OMA Device Management but they are not device independent, far from real-time and may need established IP connectivity to management servers One hotspot may provide access services for multiple Providers and one Provider may be connected to multiple hotspots. Also Hotspots may not be directly connected to Home Provider Roaming/handover decision making gets complex as it is not only based on policies how to make a seamless handover between ARs or links

4 General Needs Network assisted mechanism for target network selection Network assisted mechanism for handovers over administrative domains Three layers of handover management Local mobility management e.g. between ARs Access management e.g. across access technologies Roaming management e.g. between Providers Steering of roaming Operators have preferences.. Load balancing or e.g. granting capacity during emergency situations Preparing for operator controlled multi-access roaming Clear separation of roles: Network operator, Multi-access operator, Service operator

5 Open Issues Topics for Work/Research How does a MN inform home network about surrounding networks? inform network side mobility management entity about available target networks for the MN How does network suggest/trigger a MN to do a handover? Initial Request/Reply exchange and after that.. a possible push from network side mobility management entity towards the MN when e.g. mobility management entity so desires Should work even on flow granularity Hierarchical network information needed?...yes.. AP/AR identity, target network identity, provider identity How to gather relevant data within heteroneneous access network Ideology similar to IEEE Lightweight signalling between MN and network Part of mobility signalling? Would ease solving security issues...

6 Thoughts and Concerns Should be independent of the IP mobility solution coexist with local mobility management solutions coexist with handover optimization solutions be independent of access technology and used access authentication/authorization solutions work with multi-homes MNs work when MN is using multiple accesses simultaneously Other related tasks Level of network identity information that is required for handover policies and decision making How the MN actually collects the target network information Level of MN / AN involvement who does what and when Must be possible to demonstrate on existing networking technologies with minimal changes i.e. we are not doing a completely new architecture build from scratch without any legacy burden!

7 Example scenario

8 1/3 Neighborhood Discovery The MN solicitates for network neighborhood information AP & AR addresses Provider identities Services Link characteristics The MN maintains a cache of canditate target networks while it moves The MN repeats the procedure time to time... For the initial access the MN needs to pick up some target network that works

9 2/3 Update Target Network Information with Home Network... Initial Target Networks infoset Selected & prioritized Target Networks set Updates to Target Networks set when needed... Selected & prioritized updates if any MN initiates a HO Binding updates... MM entity Roaming Manager Updates to Target Networks set when needed Selected & prioritized updates if any The MN updates its neighborhood information with the Home network Roaming Management Server Home Network is able to mask out unnecessary target networks Home Network is able to prioritize roaming partners Home Network is able to suggest a handover to another target network e.g. during the initial update The MN does handover decisions with the help of the Home Network selected & prioritized set of canditate target networks suggestion to do a handover The MN may utilize any HO optimization technology e.g. MPA

10 3/3 Network Controlled Handover over Provider Domains Updates to Target Networks set when needed Handover suggestion MN initiates a HO Binding uppdates... Selected & prioritized updates if any MM entity Roaming Manager Updates to Target Networks set when needed Selected & prioritized updates if any Administrative decision Home network Roaming Management Server knows a good set of target networks around the MN Home Network is able to suggest/initiate a handover on the MN Home Network may initiate handover optimization procedures towards the target network if such exist The MN may utilize any HO optimization technology e.g. MPA or FMIP or...

11 Any Questions / Comments? jouni.korhonen@teliasonera.co m