DÃ©partement RÃ©seau, SÃ©curitÃ© et MultimÃ©dia Rapport d'ActivitÃ©s 2008

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Another direction is the association of WiMAXresource allocation and pricing. As alreadymentioned,WiMAX has different QoS classeseach having different parameters. Pricingpolicies can be designed in order to optimizevarious criterions: data rate sum, operatorrevenue, QoS considerations, etc.References[1] L. Nuaymi, WiMAX, Wiley, 2007.[2]Seamless and Secure Mobility,http://www.antd.nist.gov/seamlessandsecure.shtml, Last visit : September 2007[3] A. Belghith and L. Nuaymi, "Design andImplementation of a QoS-included WiMAXModule for NS-2 Simulator," in Proc. ofSimuTools 2008, Marseille, France, 3 - 7 March2008.[4] A. Belghith, L. Nuaymi, "WiMAX capacityestimations and simulation results," VTC2008-Spring, Singapore, May 0818 Extract of Pracom’s Annual Report 2008
Packet scheduling and resource sharing in HSDPAResearch Staff : David Ros, Laurent Toutain – Ph.D. Student : Kamal Deep Singh (IRISA)Keywords : HSDPA, scheduling, video streaming, subjective video qualityApplications : UMTS network, mobile multimediaPartners & Funding : in collaboration with IRISAIntroductionHigh Speed Downlink Packet Access (HSDPA)is a packet-based data service in UMTSnetworks that supports data rates of severalMbit/s, making it suitable for data applicationsranging from file transfer to multimediastreaming. In spite of the fairly high data ratesthat HSDPA offers, the shared downlink radiochannel used in HSDPA is still a challengingenvironment for delay- and loss-sensitiveapplications like video streaming.The first issue we have dealt with is thegeneral problem of resource partitioning forshared wireless links like HSDPA. Weconsidered different QoS classes or usergroups, as shown in the figure below. We havestudied how resource allocation among thosegroups, as well as between individual users,may be done using HSDPA MAC-layerscheduling.In the past, we have looked at several issuesrelated to the streaming of video over wirelesslinks in general, and HSDPA in particular. Themore recent work reported here concerns thecomplementary issues of packet schedulingand resource sharing in HSDPA.This work was performed in the framework ofa Ph.D. thesis funded by the Conseil Régionalde Bretagne, co-advised by two staff membersof the RSM department. The thesis has beenfinished on December 2007 [1].RealizationIn wired links, the task of partitioningresources (e.g., bandwidth) among flows, flowaggregates, users, etc. is relatively easy sincethe link capacity is known and fixed.Nevertheless, such partitioning is complex forwireless links with variable capacity; due to thedynamic nature of the link, it is difficult toeffectively allocate the resources (i.e., timeslots) between users who may be payingdifferent prices for different services.One of the salient points of HSDPA is the useof MAC-layer scheduling to perform resourcemanagement (i.e., bandwidth allocationbetween terminals), taking into account theradio channel conditions of all users. In someproposals, additional factors like fairnessbetween users, cell throughput or quality-ofservice(QoS) parameters are also consideredin the scheduling mechanism.Without loss of generality, we have focused onthe case in which there are two classes: oneconsists in best-effort (BE) users, and theother class in video streaming users. Existingscheduling schemes often allocate resources insuch a way that the BE users are notguaranteed any time slots; they only get theresidual time slots after the QoS requirementsof the other users are satisfied. This type ofresource allocation can cause instability, in thesense that during congestion periods the BEusers will be starved. Note that even a singleuser in a higher-QoS class, suffering with badchannel quality (even if temporarily), cancause starvation to the BE users. Starvationwill last at least for the time needed by theRNC to step in and take appropriatecongestion control measuresIn order to perform hierarchical link sharing(i.e., between QoS classes and then betweenusers in each class), a variant of an existingscheduler, the so-called Required ActivityDetection scheduler [2], was introduced in [3].Also, in order to avoid the starvation problemdescribed above, we proposed that a lowerclass be considered a single virtual user of thenext higher-QoS class. This type of allocation isthen applied iteratively for all the otherPracom’s Annual Report 2008 19
Page 2 and 3: Présentation générale...........
Page 4 and 5: Activités d’enseignementLe dépa
Page 6 and 7: Activités de rechercheLe départem
Page 8 and 9: Notre implication dans les organism
Page 10 and 11: le cadre du projet NextTV4all où l
Page 12 and 13: cloisonnement par domaine tels qu
Page 14 and 15: - le GIS ITS (Intelligent Transport
Page 16 and 17: Twente aux Pays Bas, Université de
Page 18 and 19: Liste des doctorants présents en 2
Page 20 and 21: Annexe 2 : liste des publicationsAr
Page 22 and 23: COMA-BREBEL Céline, CUPPENS Nora,
Page 24 and 25: PHAN LE Cam Tu, CUPPENS Frédéric,
Page 26 and 27: Annexe 3 : description détaillée
Page 28 and 29: Access Control ....................
Page 30 and 31: schemes specifically suitable for l
Page 32 and 33: An easy-to-use solution for IPv6 co
Page 34 and 35: Loss Synchronization and Router Buf
Page 36 and 37: Sensor NetworksRandom Walk Techniqu
Page 38 and 39: Suppressing Neighbor Discovery in W
Page 40 and 41: Media and NetworksIP-based transmis
Page 42 and 43: One of the most difficult aspects o
Page 46 and 47: classes. In our simple study case,
Page 48 and 49: Management of Multiple Access Netwo
Page 50 and 51: Adaptation of Multimedia Flows in a
Page 52 and 53: Optimized mobility management in he
Page 54 and 55: ecause it offers a generic framewor
Page 56 and 57: Future workOur next step is to fina
Page 58 and 59: Security Analysis and ValidationAna
Page 60 and 61: RealizationFigure 1 shows a classif
Page 62 and 63: Policy AdministrationResearch Staff
Page 64 and 65: execution in a distributed manner.
Page 66 and 67: Intrusion DetectionDetection and co
Page 68 and 69: eported alerts have to be managed b
Page 70 and 71: inside the corresponding detection
Page 72 and 73: function has a limitation that it d
Page 74 and 75: 1) Normal Node behavior simulation:
Page 76 and 77: negotiation. These strategies speci
Page 78 and 79: A Fast Adaptative Secure Technology
Page 80 and 81: estricted to the organization to wh
Page 82 and 83: ights and external identities, and
Page 84 and 85: Peer 2 peerP2PIm@gesResearch Staff
Page 86 and 87: Managing a Peer-to-Peer Storage Sys
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Page 90 and 91: Adaptive Application Support in Mob
Page 92 and 93: Wireless Mesh NetworksResearch Staf
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TestbedsA showroom for practical IP
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egistrar and proxies, video streami
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DÃ©partement RÃ©seau, SÃ©curitÃ© et MultimÃ©dia Rapport d'ActivitÃ©s 2008

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