Research Activities in 4G Networks at INESC Porto

1. Research Activities in 4G Networks at INESC Porto Manuel Ricardo and José Ruela

2. Communication Networks and Services Group • People • 2 professors • 2 senior researchers • 6 PhD students • 6 MSc students • Variable number of Licenciatura students • Located at • INESC Porto • “Campus da FEUP” – Faculdade de Engenharia da Univ. do Porto

3. Research in Mobile Communications – Context • Mobile communications networks vs fixed networks • mobility of the terminals • properties of wireless links • variable bit rates, variable bit error ratios • terminal characteristics • low processing capabilities, low memory, low consumption • 2 key research areas in Networking • 4G networks • Ambient networks

4. Research in Mobile Communications – 4G Networks • 4G mobile terminal • Always Best Connected to the available networks • Multiple network interfaces, of different radio technologies • Information conveyed as IP packets • Research problems include • Mobility support, routing • QoS, radio resource management, traffic accounting • Security • Ad-hoc, mobile networks • Improvement of existing PLMNs (e.g. GPRS, UMTS) VoIP, multicast • Planning, management, and operation • In Europe  focused on IPv6

5. Research in Mobile Communications – Ambient Networks • Ambient intelligence • People immersed in reacting environments • Persons carry small devices  may form a PAN • Devices • communicate over radio links; connections with neighbour networks • Research problems include • Plug-and-play of unknown devices and networks • Network composition • Mobility, security • Multihoming

6. Topics under Research at INESC Porto • Ad-hoc networking • Generic link layer • QoS, congestion control • Testing • Multicast

7. Integrating Ad-hoc with Infrastructure Networks • Ad-hoc used to extend the coverage of infrastrucure networks • Current solution implements • gateway discovery, address autoconfiguration, MIPv6, AODV + OLSR • Under work • terminal handover between ad-hoc and infrastructure modes • Multipath towards the infrastructure

8. Automatic Networking • Plug-and-play of computers and networks • Development of new signaling, which • Detects/establishes links • Detects other (ambient) networks / devices • Forms networks using existing technologies • IPv4, NAT, DHCP, IPv6, MIPv6, HIP, tunnels, IPSec, PPox, PPTP • Exchanges information about routing, security, and QoS • Addresses also multi-homing, multicast and mobility

9. Service Announcement over Ambient Networks

10. Generic Link Layer for Heterogeneous Networks – QoS • QoS reservation in heterogeneous wireless networks • QoS-enabled virtual channels between MN and AR • Technology-independent interface for 802.15.1, 802.11, 802.16, UMTS • Support for handover and multicast

11. Generic Link Layer – RoHC, Robust Header Compression • VoIP, mobile VideoIP - very small IP packets • IP/UDP/RTP headers  significant overheads • RoHC solution • Adapts the IETF RoHC to heteregenous networks • Compatible with QoS Generic Link layer

12. Generic Link Layer – RoHC, Robust Header Compression

13. End-to-End Quality of Service Framework – ScalServ • Evolved from IntServ over DiffServ • Provides end-to-end QoS to real time flows • 3 service classes, with universal semantics • Less than Best Effort, Best Effort, Assured Delivery (AD) • AD service class • Possible microflow aggregation • Uses end-to-end signalling • Interpreted at selected nodes in the access networks

14. Congestion Control • Assumption • (some) networks do not provide QoS mechanisms • but need to transport real time flows • Development of new congestion control mechanisms • preserve the network stability • are media friendly • can be combined with L4 (end-to-end) mobility solutions

15. Passive Testing – Monitoring Mobile Flows • Detection of mobile flows and representing them for • Operator: traffic maps • User: received QoS under wireless and mobile conditions • Sampling

16. Passive Testing – Monitoring Mobile Flows

17. Testing – Monitoring Platform for a 4G Operator • Passive Measurements • Traffic accounting • Detection SLA violations • User Location • Active Measurements • Bandwidth probing

18. Testing – Protocol Conformance Tester S E C I • Protocol / system functional testing • Automatic generation of tests from specifications • Tests and results obtained on-the-fly

19. Multicast • Addressed as an horizontal issue • As a rule, every new work/ thesis addresses multicast • Particular attention to video broadcast • Definition of a secure IP multicast solution • Transmission of multiple video channels • Each channel viewed only by authorized users • If a channel is not visualized, it is not transmitted

20. Testbed 1 – Infrastrucure and Ad-hoc

21. Testbed 2 – QoS Admission control + L2 link capacity renegotiated Data Admission control + LSP capacity renegotiated Admission control + L2 link capacity renegotiated Service request QoS Request Path Path Path Reserve Reserve Reserve QoS Reserved

22. Conclusions • Research in mobile communications networks at INESC Porto • Ad-hoc networking, Generic link layer, QoS, Testing, Multicast • Area appealing and rewarding for research and business • Group active at national and international level • Other national research groups have similar growth • We feel that, in Portugal, we are starting to reach the critical mass required to enable mobile communications to emerge as a relevant industry