Title of Invention

OPTIMISING RESOURCE USAGE IN A PACKET SWITCHED NETWORK

Abstract

A method of optimising the bandwidth usage on a Real-Time Protocol managed link-transporting media from a Media Resource Function of a cellular telecommunications network to User Equipment. The method comprises monitoring properties of the link and, as a result of said monitoring, adapting the sending rate over the link by re packetising media, received at the Media Resource Function from third party nodes, to increase or decrease the si7e of packets sent over the link.

Full Text

FORM 2 THE PATENTS ACT, 1970 (39 of 1970) & The Patents Rules, 2003 COMPLETE SPECIFICATION (See section 10, rule 13) “OPTIMISING RESOURCE USAGE IN A PACKET SWITCHED NETWORK" TELEFONAKTIEBOLAGET LM ERICSSON (publ), a Swedish Company, of 164 83 Stockholm, SWEDEN. The following specification particularly describes the invention and the manner in which it is to be performed. WO 2005/086404 2 PCT/EP2004/0S0229 Optimising Resource Usage in a Packet Switched Network Field of the Invention 5 The present invention relates to optimizing resource usage in a packet switched network and more particularly within a packet switched network of a cellular telecommunication network Background to the invention 10 Many operators of existing 2G cellular telecommunication network have now fitt&tatoa by *e Genoa! Packet ladat Service (OSS) aeotooole aad eyaaaaa. A typk^m IS the 3* Goaeaafoa Pataaeadap FwjecQ have kawdamiid ate concept of a Modk Reeoaaoe Raactkw QdRF) 1 vAasli k iteaded to act at a central pagans aaadia lHHtBHkME MBflte ttM* WBttBBK vVBMOflflHT 90 lOCflVBS ^IVBH AMI IK OBDBDHBOHH SMmr^vRvlBkW (WfTi) 1 nfaai iirahnai aiOriwI *Wa«doiaiayakolwh*odaceda*2Ga«t«i OaVtaCattvlfltB 3 iB 4% OQflHOaVCMOG 43BH QfcwaaBMaVn' afcC OflH QSBBME SQNftQK BHHflkiOM InRttVOOOl CI -If r Ji iF ti ii 1 m 1 ' ' i -f iflf ASVaotvsrS 25 Iowa* « fee Serriag CM Seeewi Canted Rnicta and final the MKF 1 ia oater «a eeteniea. aad ooatnt cafla, Oaoe a eaaaoa hat beea cetabnatod,aa»SaMiouaribefrMMllttlaW "Oner BavkMeaT or UB*) via the Radu Aooeat Netwwk (RAN) 6 and ta» GPRS con aetwoik7^pMStoBlarv»feGPRSCh*»«^SBp MB. b 30 Bgm 1 «Jy im^tf VrlTT— « «■— rf A» T1H« T —A flV « anoana in dotal. Tin rinaaoliianiliitwurn Ihr m tuorir and BV mfcriTWa(atratifimlliy dotted Uses) aaanhr indicate (he eachaane of data (Le. loayeenveRANi.IKfSS.etoane onattcd). 5 13:18 FROM MARKS&CLERK TO EPO HAGUE EP0450229 RL.P53006WO 3 The Real time Transport Protocol (RTP) is an Internet protocol standard that defines a way for applications to manage the real-time transmission of multimedia data. RTP is used at the bearer or media level (as opposed to the call control level which employs 5 SIP or other call control protocol) for Internet telephony applications including VoIP. RTP does not guarantee real-time delivery of multimedia data, as this is dependent on the actual network characteristics. RTP provides (he functionality to manage the data as it arrives to best effect User Plane Adaptation (UPA) is the procedure used by the MRJF and a given UE to monitor the RTP traffic between them and to adjust bandwidth 10 utilisation in an attempt to provide optimal quality during a talk session. UPA provides for the MRF td dynamically redefine the talk burst duration which is encapsulated in a given RTP packet on a given link (this parameter is known as ptime) and the codec used for that link (the codec is identified by one of a number of parameters contained in a "mode set"). The SIP message relNVTTE/UPDATE is used to signal these parameter; 15 to the UE. The UE may also send this message to me MRF m order to notify the MRF of its capabilities/requirements. The group know as the Open Mobile Alliance has developed a Push to talk Over Cellular (PoC) specification aimed at enabling the provision of services over standard 20 mobile networks which resemble walkie-talkie services, i.e. at the posh of a button a subscriber can be instantly connected to one or more other subscribers. PoC relies upon the MRF to set up and handle connections- The PoC specification describes the tools available to detect packet loss over the links between the MRF and individual Ues PoC also describes a means to request a change in bandwidth utilization, but does no; 25 provide detailed algorithms or procedures to enable this. Summary of the Invention According to a first aspect of the present invention there is provided a method of 30 optimising the bandwidth usage on a Real-Time Protocol managed link transporting media from a Media Resource Function of a cellular telecommunications network \ User Equipment, the method comprising. ;eived at the EPO on Jun 01 2006 15:18:53 Pa 01-06-2006 5 13:18 ™ MARK&SCLERK TO EPO HAGUE EP0450229 RL.P53006WO 4 monitoring the rate of packet loss of the link to determine whether the rate of packet loss is unacceptably high or within acceptable limits; and as a result of said monitoring, adapting fee sending rate over the link by re-packetising media, received at the Media Resource Function from third party nodes, to 5 either increase the size of packets sent over the link when the rate of packet loss is unacceptably high, thereby reducing packet header overhead and reducing bandwidth usage on the link; or to decrease the size of packets sent over the link when die rate of packet loss is within acceptable limits, thereby reducing die transmission delay over the link. 10 The invention is applicable in particular to networks in which the Media Resource Function is arranged to handle media distribution for Push-to-talk over Cellular services. 15 Embodiments of the present invention have the advantage that adaption on die downlink can be achieved without having to vary the packet sizes transmitted by third party nodes- Thus, transmission delays on these uplinks to die Media Resource Function are maintained at optimum levels. An additional consequential benefit is mat bandwidth usage can be adapted without having to signal to other UEs. Expensive additional 20 signalling traffic is thus avoided. Preferably, the method comprises re-packetistng received media only into packet sizes which are larger than the packet sizes in which the media is received at die Media Resource Function. 25 Typically, the step of monitoring the rate of packet loss of the link comprises sampling the rate of packet loss on the link. This may be carried out at the receiving UE, with the UE sending the samples to the Media Resource Function. The Media Resource Function adjusts the sent packet size in order to reduce the rate of packet loss on the link 30 Or to decrease the transmission delay. In particular, when the rate of packet loss is unacceptably high, the Media Resource Function may re-packettse incoming media into larger packets, thereby reducing the packet header overhead and reducing the bandwidth usage on the downlink. When the rate of packet loss is within acceptable limits, the ceived at the EPO on Jun 01,2006 15:18:53. Pa 5 13;18 FROM MARKS&CLERK TO EPO HAGUE EP0450229 RL.P53006WO incoming media may be re-paeketised to reduce the packet size, thereby reducing the transmission delay over the link. It will be appreciated that said step of adapting the sending rate is carried our 5 dynamically in response to the monitored rate of packet loss. Preferably, in the event that media is to be repacketised at the Media Resource Function, received media is stored at the Media Resource Function in a buffer until such time as sufficient media has been received to construct a packet of the necessary size. 10 Said third party nodes are typically peer User Equipment (UEs), although they may be other nodes such as web servers, etc. According to a second aspect of the present invention there is provided a Media 15 Resource Function node for use in a cellular telecommunications network, the node handling media sent between itself and user equipment over a Real-Time Protocol managed link, the node comprising: means for monitoring the rate packet loss of the downlink to the User Equipment to determine whether the rate of packet loss is unacceptably high or within acceptable 20 limits; and means for adapting, based upon the monitored packet loss, the sending rate over the link by re-packetising media received from third party nodes, to increase the size of packets sent over said downlink when the rate of packet loss is unacceptably high, hereby reducing packet header overhead and reducing bandwidth usage on the link, or 25 to decrease the si2e of packets sent over the link when the rate of packet loss is within acceptable limits, thereby reducing the transmission delay over the link. Brief Description of the Drawings 30 Figure 1 illustrates schematically the architecture of a cellular telecommunications network employing a MRF node to coordinate VoIP voice conferencing; and Figure 2 is a flow diagram illustrating a method for adapting bandwidth usage on a link of a VoIP voice conference. Ceived at the EPO on Jun 01,2006 15 18:53. Pa-- 5 13: 19 FROM MARKS&.CLERK TO EPO HAtGUE EP0450229 RL.P53006WO Detailed Description of Certain Embodiments Considering now in detail the PoC service, a single MRF can manage thousands of talk 5 sessions, with each session being independent from other sessions that may be hosted by the same MRF. A given talk session will comprise two or more pieces of user equipment (UE) and the central MRF. These UEs might each have different capabilities. Talk bursts from a U£ are encoded and sent to the MRF (via respective GGSNs) as one or more RTP packets, referred to here as simply "packets". The MRF 10 then forwards the packets to the or each other UE participating in the same talk session. The path which the packets take from the UE to the MRF is called the "uplink". The ceived atttie EPO on Jun 01, 2006 15:18:53. Pa~ c ~' "c WO 2005/086404 7 PCT/EP2004/050229 pafliwhichpw&BtstakBfiamtieMBFtotelJEttcallfldte'Vkmnaiil^. The rate of packet toss may be different for each link in fhe chain. Particularly for real-time applications audi as VoIP, the quality of fee perceived user experience is critically dependent upon fhe rate of packet loss. A talk session involving ten UEs will involve 5 twenty different finks (UB to MRF and MRF to UE) and therefore Iworty different potential trouble areas. As set oat above, User Plane Adaptation (UPA) is the procedure used to detect and then reduce packet km for fhe duration of a talk session. Once it has been determined that 10 foe leVd of pacto low occurring on a grvenhnkkanft^^ service quality, fhe UPA procedure will act to reduce packet loss. The only practical tool available to fhe MRF and the UEs for achieving oris result is fhe redaction of bandwidth usage on the troubled Hole. Bandwidth can he reduced by using a higher nwipH, asm rate codec and/or by iwkw'iug transport overheads by sending larger 15 packets. UnJfcklteketLosS The MRF kioapoaato for dotocu^ packet kan on die iglin^ AUBis notifial of paite loss by the MRF sending to MariRT^ AKR 20 provides fhe total number of packets last aasae fhe talk aesakn began. The packets lost over a given taflr burst can be cakolaaedby anbtiacnag fhe packet kiss identified in fhe latest report from that identified in fhe last received saport. 25 The UE is responsible for detecting packet loss on the downlink. The UE will send an RR to fhe MRF after each talk burst is received on fhe downlink, thereby hiforuuug the MRF of any lost packets. A packet receiver (at the MRF or UE) detects packet toes by measuring gaps in the RTP 30 sequence numbers wed in a packet stream. Let St be fhe Inghest seqoerioe number received, let Si be fhe lowest sequence number received, and let P be fhe total nmnber of packets received. Then fhe munberoflost packets is: Lost-((S*.Sd+l)-P WO 2005/086404 PCT/EP2004/050229 As some packets may be duplicates, it is possible to arrive at a negative value for me number of packets lost This is inoooaeqnential hero. TmaasapfemrmiibceqRiinsmat the RTF sequence number umamtoiriftdmronghoat me talk session (allowing for wrap-around of sequence numbers), and is not sestarted at the beginning of each butat 5 Throughout a session, me MRF and UB can detect me loss of packets. However, an oorasioMl kaa of packets shoold not trigger link adaptation. Rather, adaptation of the link should be triggered only by continued r«cxBtk)n over rnany samples. Packet loss samples are taken peaodicany, occasionally triggering bandwidth adaptation if 10 continued loss k evident A sample loss rate is calculated far each Mnk at the end of each talk burst received on nrth^ or wlmn a receiver report (RIQ arrives. The sate afloat for a single sample is the number of packets lost since the last sample. Tne taw oflcas over several samples is IS UKaveots^sacnple loss rate. The loss analysis una wduw? uses five parameters: 1. Tlw sampled toss, £. 2. TfeacanberofsarDplmA'requiredmcadertocalort 20 Thet&tf lam M^*btttRL~^-14*1^^^**^100* toce^ sampled loss. 3. The aooeutsble rate of loss. ChalmisTalne^JtL 4. The time mat must pass between aiteua.M's to porfow bandwidth adaptation. Call uns value T. This value may be defined in terms of samples rather man 25 actual time. Once me node has garnered .V samples, it can begm to calculate XL. The rate of loss catenation only mcmdes me last N sanmka as defmed by a sWing wiridW irfikih is advanced by cme sample each tkne a new samr^ k obtained. If RL exceeds the ARL 30 value and a time That passed since the last link soaptatkw, una a bandwidm adaptatkm procedure is initiated. The MRF will be configured with flic values for N,ARL,aaAT. The DE may be shnflarry configured, or these values may be hard coded. WO 2005/086404 PCT/EP2004/050229 Once a bandwidth efficiency improvement measure has been applied to a link, it k said tetu» link has been'downgraded'. Links trial perform well in a downgraded state may be upgraded later. A Blue that has bem previously downgraded wfflb well either because the new bandwidth utilisation is ideal tor the link conditions, or 5 because the problems causing packet loss have dissipated. Therefore, me UPA process should upgrade a previously downgraded fink after some period of good performance. B is necessary, therefore, to define good performance and the period of good pw CM immfW thattmurfp—a hnSnrn iiMnpn^Hig ^n ^ipgiwfr» 10 GoodjWTfiyrramne is reached when the rate of km remairis below or at the , This performance must be luaiiiUiued for some period called hew good performance time(GPr). The GCTshotiM be greater than 7. If me mte of IOM ever exceeds me il^valne, men perfoixiancekoonsideredpoor again, an^ Only after good pcrfonnance has been maintained for a period equal to or greater man GPT, can 13 oie hnk be upgraded. Once the MRF or the UB dun-manra mat bandwidth adaptation k required, each may eepaiately imtkte a bandwidth adaptation procedure. It k possible for both me UE and ate MRF to initiate bssidwidm adaptation TJrisk 20 allowed by me PoCapeci3cafion. However, it k win wary for bom me UB and the MKP to initiate bandwidth adaptation lapocdores. bkracommendedmataUEhononni a uewptime value and mode-set when it recer«esanyreINVrrEAJPIlATlKono»t,but that me UB does not actually monitor or perform media changes itself, Le. the UE should not ilaelf initiate baiidwidmarlaptat^ 25 30 As each link •Johns*' a talk session, the link k grvta a grade tltat deteimmef the granted ptime «nd mods-set (codecs) that may be used on me Hnk. Bandwidth adaptation awolvBidowiigiadmgornpgradmgtte on mat Hnk. The flow diagram of Figure 2 illustrates the method of adaptivery varying bandwidth WO 2005/086404 PCT/EP2004/OS0229 to ConsideiLag now each of the various components in detail: Media Resorace Fraction S Uplink The MRF can request mat a given UE attempt to use less bandwidm on the noting: in oider to reduce packet loss on that fink. This is accomplished by sending a relNVITE/lJPDATE with an SDP (Session Description Protocol, RFC 2327) that requests a higher J>WM« value or a lower bandwidth codec This request is sent oary to 10 the UE tranaantting on the troobtod inilink. If the cuxrentinW value has reached me wmptime for Oat Hnk and me lowest rate codec available to an participants k already being used, then farther adaptation cannot be initiated, Downlink IS The MRF can attempt to improve downlink pcri«»M^ 1. Reotgnaise me packets for Oat link in such away to to packets require lees lkA^kri^^^^flS^BV *sl^L£d M■ ■ rti ■ M * — —^sj m Jt ■■ - — —J—^* —*^ — — UCBXnVKKD* IJDkl MWWlRMff JJB CBUOVa SCPBCSMBUSSVDUD* 2. Request mat anoomUEsm the aeaambegm to send more ba^ packets. This memodis called Least ComnonDessnmaaaar. 20 ftmaybepoasMetocofflbmemcsemothodr.faex^^ basis, whilst requesting lower bandwidfli codecs from all UEs. Considering aoaation 1. above, die MRF could rearrange padoets before aondaie them on the downlink. This could mean transcoding to a mote bandwidm efficient codec, 25 nsing larger packets with a lower overhead, or a combmation off both. However, under the current proposals, nie MRF is not capable of transcoding, which leaves only the option of building larger packets. In order to create larger packets, (he MRF must buffer, on a downlink4>y-downlmk basis, snialkr packets until a padoet of me requhnd size can be composed. If a talk burst ends before enough packets are collected, men 30 whatever packets have been buffered are used to build the final packet which is sent immediaterytotheUE. As the largest packet corresponds to a 400ms speech burst; this approach will result in the buffering of no more man 300 bytos per downlink. This is considered manageable. WO 2005/086404 PCT/EP2004/050229 An assumption is made tot w-packatisation is used only to create packets which are larger ton those corresponding packets received on to upfok, Le. le-packctisatiofl is rot used to break im received packets into sniaUer packets. Of comae, flris possibflny is 5 not excluded. The main advantages of Ibis approach are: The performances of to remaining downlinks do not suffer due to a single problem fink. 10 • It does not require to cooperation of to UEs. It d\>ee not require signalling of new jrt^ vanes. The main disadvantage is: ft requires more complexity into MRF processor (MRFP) to handle packet IS Considering now solution Z, mis approach requires tot afl UBa begin to send more bandwidth eflk.ient ymJueH on their uplink in older to give better nrrftwii—KC to a singfetionbfeddownfink. Tnis approach reqimea tot a relNVITE/UFnAlS be sent by to MRF to each UB m order to move participating UEs to to new media values. 20 The mam advantage oftUs approach is: The MRFP k not reaponsmte for nianipnlah^packetr All finks in to session may be subject to longer delays andfor use lower rate «*" *" «*■■ *" «v»««wh 25 because of to need to buffo nmtounitt an an»^ packet sine has been received. If a UB ignores to new ptime value (notified to it in to relNVITE/UFDATB message), packets from tot UB may still be lost All npgodeAdowngmde uiuuedures most consider to lowest attribute of all 30 participants before Inking any action. A considerable amount of additional network signallmg k leooired whenever a fink grade changes. WO209S/MK44M ICT/Et>2004/»5»229 ft ft is worth considering the affect of these sotatioos when UBs ate added to or removed from an ongoing union. If fee lepiirl nation approach (sofatiee. 1.) is need for downfaak adaptation, men no special action is reqoired to adjust tbe/time vatoe when a rate htoitingUBfcai^ or joins a session. * V—T*-*1^ T*«^r'"*—*"• "-I-'T^" S approach (solntion Z) is need, free oawaining UBs Must be notified of the now jrttoe 9e*tmgrfitJshisJiirorViwri than toe esiating settings. The Adaptor Mpto Rate codec defines eager modes of opciaisjB. Different] ^p** ff*ffimffit alwfHH i ♦* Ffyeit aW difftriT-"4 IIWHIT > A handset is able to supply a nst 10 of snppcetodnaobes, ora'aaode-set". to order to duaumtof. a mode acceptable to al UBs m a sends*, too MBF MCWCS a nwde-set fion each TO, and selects a nude at sbtoilwinto intototiaa iinsrinitj need, toeliRPi IS toeaBBdesetaarfliyaMP&fcntoiBliwrtietiaCaMi I Ift InlC IVWsTt BttftCaVnWg UDWJMBBBW TMBS JsnMttM Hktt jnTttCSCCteMaaV Of tWiirriii|sliieachlaaieaPEjeaMeeleasests^jiiaiiML ITfee estlm i imaiaiiiatiiltnl 20 A carefid rw'aVirtiiia of to» ^arioas lototioas mnsidmd above leads to toe coBclnsion that me cs^aaal etilatinn is Ihat wine h involves toese-patlBliesHnn of media attteMedtotoaonweBaBtliinisriorto This ntonmises or efinaaates acldttanal sisaaBiag w^ other UBs to be ■—■■««hf1i at an optimal level toldng into account toe desire to 25 minimise tianssainaon delays. Other codecs such as EVRC (used by CDMA handsets) do not make ose of toe concept of mode-sets. 30 User Uptink WO 26*5*06404 PCT/EF2604MS0Z29 /3 A UB may decitest bandwidth iwilirjiimi on the nphnk by rl—igiiig to a lower bandwidth codec, by sending lamer packet*, or asmg a eombejenon of both action*. TheUBdoe«aotDetdtoa«MteaaeofalDe>erj)ttMvakie,butitiaa7*otiaea vafec lower ten that specified by fee MRF or a value higher than some tmxptime 5 value. The UE does aot need to a%aal1)ieii3e of a lower late codec, bat k nary oajyose rortrninmi iminUmnrir ml ■ii.iiallrilbjlhr MET A OB may acquest mat me MRF aead mom bandwidth efficient packets on the 10 iliniasna I) IHIBIHI iiirnTTTTTmrnTTnii Ihi lirr nilli >n ilis|Hi JLJbO AfltF ataW mWaMNaY aft© SCMMflet waflftseWmnelY wMWenOsseK Css* T^nWCesi OVWDaasMC DMnQWldB SaafHRM wHOMat * V *nVfc Asm Cesewff GK eaTsV auCenVC l^OTssaTDOam AJBaaWeTanfanwMsm anPOasQeManV ■a MRF wi ynaH an apsBasatote ■JHVIIPDi'DAIE aad aen* » to aM omcr IS irninnnatim muw*,*^ham*^mpe*hyhaBbni*mim iehowad par kits ^BjJ yw^yl^a^ aaWMeaT fffana^sasnnt asm* asms* BBBsVassaTannnnnt- V enMflanf ■§) BMBOCMCC eweC OCBBCHK^C » JBBML VMP KT ■BC ■*• HMHC saVv eewuesesM-E ■Bd aMMMaaaaBg of aaata. nr eaaaaaae, one aaajK ssaae nets acccatnae; ID a \ to a 20 sc»le>wk«mtfeatosmwfefemenenfetnn^ TJmmtaaamatsm*meyteeViMemdri Bach ink gtademnpsteaspntalicjiwwH, lahw aad mode-set Qnr.lndmg codec) that may be wed on lae fink. The ipecific chaagea at each level may be confignnrbte. Table 1 below shows an example of how the moda-sat and/Kane vanes might be set tor each of the 25 tinkgtedes, where the mode-set shown hv&ides modmO and 1 feme AMRcooec. m me table, commas 3 and 4 indicate for each giade me bandwidth m kbps which win be reqmredtosnppoitinodeO and mode 1. Was a new UB is added to a session, that UB speofiei(m the SDPINVTra message) 30 inedkperaaaes^tliatconcaposritoiteundcts^ The mode-set specified by me UB represents all of the modes Art it supports, atrifanrnxe the MRF will always take toe intersection of the mode-«et imtiaty offered by the UB and the mode-set selected based on the link's grade. The MRP should assign an initial WO 2M5/M6404 PCT/£P2*M/»S0229 »t grade to die Hnk based on the/case value oflbsed. link upgrading or downgndsng SIBfEf Iran ne tnsnei gEaoe: The MBF mnst be updated in order to perform User Plane Adaptation. The idNVITE/UPDATE BgnalBng is atieady snppected in die MRFC and nWeftm no changes ate ucteasarj. AO changes will be made in me MRFP as described in me following! WO2M5IM6404 PCT/EPZ»M/05©:Z29 Tecamcal Owhne MsdiallesowcePiMclfengtocewor S CtMfl&wafkm Pmvmttttn operations aad inasatenaoce intefbee. Tbe VirtawFD POT should be updated to coataw these new values. 10 iMiliianaiatliasiifml' -*« 3* to 1000,aVIawHOO VtetoMeNMoniiom ***** **■" 30 1o MOO, Mao* SO Value to—ewauiiTaiii m jITmi saaaples M»BH 1 to MOO, Nuafeer of samples to we when •HKWS nl[awlfaj,iii nflim rtimayirtrMwnwiurj iatoaar S to 1000, fteoneacy of totjas; five dawapade dtfeWtlO weaawea given in saaaples. Owed Tatweovtsview. Ml float OJ> to 100, Acrtptaik rate of toss. Called ARL default 1 Mnc owuvi&vf. opgnwiciPWycy iateger 5 to 1000, Flfiyttmcy of taking link ippgnptte de&olt30 measwe*. gnfcSfcfM wtoger 5 to 12; Nwnber of steps to we in a link default 12 grade. This value it wed to create a grade table based on the mm and max ptinoe values. jPcj/w'/miwcc Jafefls w ttnents Inocdertojnd^1heqpamyoftenetwod:aiKlnwe£K«iveiiewofteUPApcocedDTe IS and cenfigwatkm, new perfwnance measurement WO 2005/08M04 PCT/EP2WW/05022* should be stepped each time a fink is downgraded and bandwidth A counter should be stepped each time a tink is upgraded and bandwidth The average nee of Ion far all links should be reported periodically, pemaps at The average fiafc asade far all finks should be leported periodically, pemaps at 10 > sat asorideiby each OB save turn to saber DBS mat join a tscssaeleaatoiBesedtoasv/IKaetaesesssme IS I sssfssssassssftssi pawuaaafc Aa each pasMcajss* faiee, amir SW w9 isclssle me saoeVsat witt itek UB suppests. Thia set is a series rf ■malm fa— 0 to 7. The set shsnld be 20 casvyesseaTto ntsssasD, far caasnplec MooVset: 0,1^7 accomes 10000111 The MRFP stoics Has bitmap with data about each partidpant (PdVember class). The MRFP keeps a recced of the ennent mode-set in use wim the session, also 25 staled as a bitmap. This mode-set starts oat as 11111111 far a new empty When a participant joins, thstpwuupauftinode-eetiB'anded* wimthecrawrt mode-set The icwk is ased m me answer S».ff the resutt is O.nxsUE must be rejected and me current sat does not change. If the currem set tau changed as 30 aiesukcfacceptiDgtlwiiswp^rticfaan^ ofleml to all ctsgentp^srticipairiB. When a DB exits the session, me current mode-set for the session is re-catenlated by iterating through the list c€ remaining pejtkapents, and "anding" W\l iWjfl^WW^ PCT/EP2084/050229 I? (together. Tbe matting mode^ becomes the anient act If it is different fin the mode-set in nee befcse the TJB exited the session, a new SDP most be generated and offered to all remaining partiripanti Tbe cnaent mode-set nrme session may be "anded" with the set required doe to me User Plane Adaptation procedures, ffit changes as a result, a new SDP must be fjrffwatfii and f1*^'*" ** M* pft*tiiipiifl4T at me end of each Ante Ins* jfiashtw 10 EssfleaMntaunn preys 15 tanjtrsatsnnsisai aanfaaak nncn riOMBanecr cssse an nave na msianee or me isnnQassnmAnspssnssi class. AM packets pniieawd by a WMcaater wfll be passed to me Bandwidth The Bandwidth Adaptation class has buffeted psevious packet* it wil add me packet to its insfirnal buffer. If the buffet has mchfd the muiiiaan retained size, 25 it will be sent The Bandwidm Adaptation class most be notified when me floor is released. Any buffered dsiak sent inmiediately upon this liodfication. If a new packet for me snwnbnk arnves mat is smaller man the rmnimran a&Wed; and the binfokenipty, men me packet wfll be pbwedm If 30 the packet is greater man or equal to me nnmmum size, then ft will be sent iHiHieniately* The PdMember wiB infirm me Bandwidm Adaptor each time a new Rate of Loss valne is calcinated. The Bandwidm Adaptor will, using the configured W0 2M5*M4frl PCT/»20©4^5»2» valnesBYT>A»X,Hmd or duwHfjwifid mom na cmcnt position If a dowasnsVs gode m 5 If^i^JiaaAgp^krt^iyrt, flKaanc^SDPwfflbecoaipntcidandsentoo mat link, Xsvir ffvding Mntki KnuyntlatiKit 25 lmplcinrahni The MRFP should accept new SDP ofltaa during a session. The remote end may change me mode-cet it accepts or reqnest a difierantpttse. Other changes should lesnlt in me offer being rejected. (Optionally, if tmie permits, we could accept anew sddsess and port) 30 These offers can change the grade of the downlink. A new grade should be assigned based on mis offer. The bandwidth adaptation methods should be applied as though me downlink grade has changed based on me packet loss analysis procedure. WO 2M5/0M404 PCTAEP2004/OSe229 T^3mwaS»dK»MhcffiaatkdmkitekxatdUttdoal^a^tatettiD^ cDfXGnJftjra User Phmt Adaptation Teat Tool 5 ft (boitf be poaAfc to nasi tool doling batic It* art UPA pmewluM m woririag at wprrtrd. Thai meaac the tool abooU naxriate packet low on bo* lae npfiak aad domnnnk in a predictable way aolbet Ike behaviour of the MRFP can be obeerad. The tool ahonld akw accept and lunajly to newpttme and 10 Grade ptime 4.75 kbps 5kbps 8 80 10.2 10.6 7 100 92. 9.6 6 120 85 8.9 5 140 8.1 83 4 160 7.7 8.1 3 200 7.2 7.6 2 260 6.7 7.1 1 34ft 6.4 68 01-06-2006 i:"'ly TO EPOHHGUE EF-,450229 RL.P55006WO 21 Claims 1. A method of optimising the bandwidth usage on a Real-Time Protocol managed link transporting media from a Media Resource Function of a cellular 5 telecommunications network to User Equipment, the method comprising: monitoring the rate of packet loss of the link to determine whether the rate of packet loss is unacceptably high or within acceptable limits; and as a result of said monitoring, adapting the sending rate over the link by re-packetising media, received at tbe Media Resource Function from third party nodes. To 10 either increase the size of packets sent over the link when the rate of packet loss is unacceptably high, thereby reducing packet header overhead and reducing bandwidth usage on the link; or to decrease the size of packets sent over die link when the rate of packet loss is within acceptable limits, thereby reducing the transmission delay over the fink. 15 2. A method according to claim 1, wherein the step of monitoring the rate of packet loss of tbe link comprises sampling. 3. A method according to claim 1 or 2, wherein the step of adapting the sending 20 rate is carried out dynamically in response to tbe monitored rate of packet loss. 4. A method according to any one of the preceding claims, wherein, in the event that media is to be repacketised at the Media Resource Function, received media is stored at tbe Media Resource Function in a buffer until such time as sufficient media 25 has been received to construct a packet of the necessary size. 5. A method according to any one of the preceding claims, wherein said third party nodes are peer User Equipment (UEs). 30 6. A Media Resource Function node for use in a cellular telecommunications network, the node handling media sent between itself and user equipment over a Real Time Protocol managed link, the node comprising: =eived at the EPO on Jun 01, 2006 15:18:53. Pa- 01 -06-2006 ° 13=19 FROM MARKS&CLERK TO EFO HAGUE EP0450229 RL.P53006WO 22 means for monitoring the rate of packet loss of the downlink to the User Equipment to determine whether the rate of packet loss is unacceptably high or within acceptable limits; and means for adapting, based upon the monitored properties, the sending 5 rate over die link by re-packetising media received from third party nodes, to increase the size of packets sent over said downlink when the rate of packet loss is unacceptably high, thereby reducing packet header overhead and reducing bandwidth usage on the link; or to decrease the size of packets sent over the link when the rate of packet loss is within acceptable limits, thereby reducing the transmission delay over the link. 7. A method of optimising the bandwidth usage on a Real-Time Protocol managed link transporting media from a Media Resource Function of a cellular telecommunications network to User Equipment substantially as herein described with reference to the accompanying drawings. 8. A Media Resource Function node for use in a cellular telecommunications network substantially as herein described with reference to die accompanying drawings. Dated this 8th day of September, 2006. Q OFK&S AGENT FOR THE AP ;ervecl at the EPO on Jun 01, 2006 15:18:53 Pa _. „ o ~x -« AMENDED SHEET 23 ABSTRACT OPTIMISING RESOURCE USAGE IN A PACKET SWITCHED NETWORK A method of optimising the bandwidth usage on a Real-Time Protocol managed link transporting media ftom a Media Resource Function of a cellular telecommunications network to User Equipment. The method comprises monitoring properties of the link and, as a result of said monitoring, adapting the sending rate over the link by re packetising media, received at the Media Resource Function from third party nodes, to increase or decrease the si7e of packets sent over the link.

Documents:

1094-mumnp-2006-abstract.doc

1094-mumnp-2006-abstract.pdf

1094-MUMNP-2006-CLAIMS(AMENDED)-(22-6-2012).pdf

1094-MUMNP-2006-CLAIMS(AMENDED)-(24-9-2014).pdf

1094-MUMNP-2006-CLAIMS(MARKED COPY)-(22-6-2012).pdf

1094-MUMNP-2006-CLAIMS(MARKED COPY)-(24-9-2014).pdf

1094-mumnp-2006-claims.doc

1094-mumnp-2006-claims.pdf

1094-mumnp-2006-correspondance-others.pdf

1094-mumnp-2006-correspondance-received.pdf

1094-MUMNP-2006-CORRESPONDENCE(15-10-2012).pdf

1094-MUMNP-2006-CORRESPONDENCE(25-8-2014).pdf

1094-MUMNP-2006-CORRESPONDENCE(26-11-2012).pdf

1094-mumnp-2006-correspondence(26-3-2008).pdf

1094-MUMNP-2006-CORRESPONDENCE(27-5-2011).pdf

1094-MUMNP-2006-CORRESPONDENCE(9-6-2014).pdf

1094-mumnp-2006-description (complete).pdf

1094-mumnp-2006-drawing(12-9-2006).pdf

1094-MUMNP-2006-DRAWING(14-6-2012).pdf

1094-mumnp-2006-drawing.pdf

1094-MUMNP-2006-EP DOCUMENT(14-6-2012).pdf

1094-MUMNP-2006-FORM 1(15-10-2012).pdf

1094-mumnp-2006-form 1(27-10-2006).pdf

1094-MUMNP-2006-FORM 13(14-6-2012).pdf

1094-MUMNP-2006-FORM 13(15-10-2012).pdf

1094-mumnp-2006-form 18(14-2-2008).pdf

1094-mumnp-2006-form 2(title page)-(12-9-2006).pdf

1094-MUMNP-2006-FORM 26(14-6-2012).pdf

1094-MUMNP-2006-FORM 3(14-6-2012).pdf

1094-MUMNP-2006-FORM 3(26-11-2012).pdf

1094-mumnp-2006-form 3(26-3-2008).pdf

1094-mumnp-2006-form 3(27-10-2006).pdf

1094-mumnp-2006-form-1.pdf

1094-mumnp-2006-form-2.doc

1094-mumnp-2006-form-2.pdf

1094-mumnp-2006-form-26.pdf

1094-mumnp-2006-form-3.pdf

1094-mumnp-2006-form-5.pdf

1094-mumnp-2006-general power of attorney(12-9-2006).pdf

1094-mumnp-2006-pct-search report.pdf

1094-MUMNP-2006-PETITION UNDER RULE-137(14-6-2012).pdf

1094-MUMNP-2006-REPLY TO EXAMINATION REPORT(14-6-2012).pdf

1094-MUMNP-2006-REPLY TO EXAMINATION REPORT(22-6-2012).pdf

1094-MUMNP-2006-REPLY TO HEARING(24-9-2014).pdf

1094-MUMNP-2006-SPECIFICATION(AMENDED)-(27-5-2011).pdf

1094-MUMNP-2006-US DOCUMENT(14-6-2012).pdf

1094-mumnp-2006-wo international publication report(12-9-2006).pdf

abstract1.jpg