1 WP2.5: Definition of the network architecture

2 Outline About M20 Analysis of business models Analysis of physical and link layer Topology under consideration Basic assumption Authentication and security QoS Routing Network management Conclusion

3 M20 Definition of network architecture including management facilities

4 Business Models Roles: Network operator: provide network resources and service infrastructure to the service providers Service Provider: at least maintains customer relationship and do billing Subscriber: subscribes to different services The relationship between the network operator and service provider and their role in service creation and delivery is important from the network architecture view of point. Current trend indicates the growing portion of “zero” service providers (e.g. ADSL) The network operator does all works, The service provider does billing and maintains customer relationship

5 Business Models HAP network operator Other network operator Other network operator Other network operator …… Network operatorsValue added service operators Service Provider Service Provider Subscriber

6 Analysis of Physical and Link Layer Authentication: support user authentication in LL Not per-user, but per-terminal (X509 certificate) Each BS has its own authentication database Security: has security mechanisms at LL PKM key management mechanism Adaptation between MAC and upper layer QoS mapping IP address and MAC address mapping Scheduling

7 Topology under consideration HAP1 HAP4 HAP2 HAP3 Optical link We consider the network topologies with inter-platform links and processing on board

8 Basic Assumption Basic assumption: IP in the network layer IP technologies (IETF standards) should be applied Problems related to HAP and the provision of targeted services should be identified User authentication, authorization Security Routing: unicast and multicast QoS Network management Mobility support Possible technologies such as MPLS, provision of IPv6

9 User Authentication NAS Diameter server User CPE=layer 2 gateway Networ k Subscriber credential Access-Request Access-Accept NAS Diameter server User CPE=NAT server Networ k Subscriber credential Access-Request Access-Accept IP address (a) (b) Candidate AAA protocols: Tacacs+, Radius, Diameter Diameter is the best-suited AAA protocol for Capanina

10 Integration of authentication and security mechanisms with Diameter EAP integration into PKM messages. Terminal-based authentication user-based Distributed user database

11 QoS Architecture Terestrial network Satellite Gateway HAP Access link (IntServ/DiffServ) Inter platform link (DiffServ) Backhaul link (DiffServ)

12 QoS mapping Helinet: mapping of IntServ and DiffServ into MAC QoS Open question: How to map IntServ QoS classes to DiffServ classes?

13 APS Scheduling Algorithm. The objective of the algorithm Enhance overall throughput Guarantee the long term fairness Provide a minimal throughput per user Download direction Can be implemented on HAP Takes adaptive burst profiles into account

14 Performance Evaluation of APS Improve app. 20% of system throughput

15 Routing 1 Unicast routing for point-to-point connections Inter-domain BGP is scalable, efficient and widely deployed suitable to inter-work with Internet Intra-domain Link-state vs Distance-vector based routing Link-state algorithms provide better performance Better scalability Faster convergence even in case of radio link errors Simpler management OSPF vs IS-IS The two most popular solutions Offer nearly identical service and performance IS-IS slightly more suitable to use on HAPs The most significant factor in choosing is probably the familiarity and comfort in both engineering and operation!

16 Routing 2 Multicast routing Efficient handling of multicast services Video on Demand, Video Conference, Phone Conference, Massive Multiplayer Online Gaming Traffic traverses tree(s) spanning IP group members Source based trees for groups with a few sources (e.g. VoD) Shared trees for groups with multiple sources (e.g. Video Conference) IP group management IGMP to handle JOINGROUP, LEAVEGROUP messages and poll reachable members Definied only for Ethernet Broadcast medium for both direction of dataflow supports only down-link multicast at the link layer HAPs must provide IGMP service for SSs

17 Routing 3 To join a group a SS must connect to the HAP and on the channel it sends the IGMP JOINGROUP message The HAP creates a new CID for the IP group (if necessary) and initiates a new multicast connection with the SS To query the SSs the HAP sends an IGMP QUERY message on the multicast channel, SSs respond like in the Ethernet case The HAP must forward the response to the related multicast channel to notify all group members

18 Routing 4 Intra-domain Several solutions with different objectives DVMRP, MOSPF and PIM-DM for dense mode services MOSPF provides a robust, fast converging solution but needs OSPF for unicast routing DVMRP and PIM-DM converge slower PIM-DM is absolutely „unicast independent” PIM-SM and CBT for sparse mode services Lack of robustness: single point of failure! Slow convergence Inter-domain Still under research, no widely accepted protocol HDVMRP to connect to MBone (multicast capable Internet hosts) BGMP and MSDP might be the winner in the long-run

19 Network management Proven network management standard SNMP is recommended MIB database for SS and BS Roaming and mobile station (train) association with HAP

20 Conclusion Define the network architecture based on Business models Physical and LL of standard The network architecture is IP-based, then a lot of proven technologies are available for use Identification of the problems related to the deployment of IP-based technologies on the top of Areas of interests: authentication, routing, QoS, network management

21 Document Properties