Chapter 3: Dual-bandwidth Data Path and BOCP Design

Transcription

1 Chater 3: Dual-bandwdth Data Path and BOCP Desgn 3. Introducton The focus of ths thess s on the 4G wreless moble Internet networks to rovde data servces wthn the overlang areas of CDA2000-WLA networks. In the overlang area, the user s requests are sent out through CDA2000 networks and the rely through WLA networks. In order to do ths, the Dual-bandwdth data ath and the Bandwdth Otmzaton Control Protocol (BOCP desgn wll be roosed n ths chater. Ths chater wll be dvded nto seven sectons: Secton 3. s a bref ntroducton and the roosed soluton of our research. In order to understand the valdty of our research, we wll resent a mathematcal model n secton 3.2. The detaled methodology dscusson of the Dual-bandwdth data ath desgn s n secton 3.3 and the BOCP desgn s n secton 3.4. Secton 3.5 dscusses the functonalty of the BOCP desgn. In secton 3.6, we wll lst the erformance metrcs of BOCP desgn. Fnally, secton 3.7 s our conclusons about ths chater. 3.2 athematcal odel for the BOCP Desgn The urose of the Dual-bandwdth data ath s to mrove the throughut and get hgher data rates n the CDA2000-WLA ntegrated network. Cal et al. defned and develoed an analytcal model [80 to calculate the ntegrated network throughut. Followng the analytcal model, Ge et al. develoed and extended mult-class model [8. In both researches [80 and [8, messages are transmtted n a slot wth a 3-

2 robablty. We alyng the methodology to develo and exlot our methodology to calculate the throughut wth the BOCP rotocol. We assume that PDS selects WLA n a slot tme wth a robablty as well. As gven n the mult-class model, the system throughut R can be defned as B[ L R ( B[ T s Where B s the average message length of BOCP, and B T s the average [ L length of vrtual selecton tme, whch s defned as the nterval tme between two successful selecton as shown n Fgure 3-. [ s Fgure 3-: A vrtual selecton tme Followng the Fgure-, the exresson of B[ T s s derved n (2 and (3 as B[ T s B[ dletme + B[ collsontme + B[ successfultme (2 Where B [[dletme s the average consecutve dle tme; B[ collsontme s the average tme that the channel s busy due to a collson; B [ successfultme s the average tme requred to comlete a successful selecton. ormally, after many tmes faled a successful selecton can be done. We assume 3-2

3 that there are c [B tme collsons n a vrtual selecton tme. The case has been shown n the Fgure 3-2. Followng the methodology, the Fgure 3-2: Vrtual selecton tme B[ T s can be exressed as B[ T B[ dletme( [ B + + B[ collsontme [ B B[ successfultme (3 s c c + Consderng WLA system and CDA2000 system n whch there are traffc classes and n (,2,..., statons for class- traffc, the dervaton of total number of c [B for the mult-class traffc can be founded n [8 shown as follows: ( c[ B (4 [ ( (, We assume that an dle tme slot st dletme and a collson tme st collsontme, then the B [dletme and B[ collsontme can be found n the [8 as follows: Where we assume that ( B[ dletme. T dletme (5 ( ( B[ collsontme. T collsontme (6 ( s the selecton robablty for CDA statons. s the selecton robablty for WLA statons and 3-3

4 3-4 We alyng the formula (4, (5 and (6 n to the formula (3, then we can get [ s T B. Followng the methodology, we alyng formula (3 n to formula (, the throughut R can be exressed as follows: [ [ s WLA L WLA B T B R (7 [ [ s CDA L CDA B T B R (8 From the two formulas (7 and (8 above, the throughut raton between WLA and CDA traffc can be calculated as follows: ( ( * [ [ [ [ / [ [ CDA L WLA L s CDA L s WLA L CDA ELA P B B B T B B T B R R r (9 From the two formulas (5 and (6 above, the raton of [[dletme B and [ me collsont B can be calculated as follows: [ [ collsontme B B dletme λ [ * * ( ( * ( ( * ( ( [ ( (, collsontme B T T dletme dletme + collsontme dletme B T * ( ( * ( ( ([ (, collsontme dletme B T * ( ( [ ( collsontme dletme B T * ( ( ( (0

5 In the formula (0 above, the ( f (, ( [ + ( 2 ( ( 2 f, * + *[( f (, 2 f (, * ( 2 Where f (, s a factor between the and. we alyng Taylor formula and then get the formula ( above. ow let x (, b a 2 *[( ( can be rewrte as 2 f (, From the formula (2 above, a 0 f (, 2 2 d ax + bx 0 (2 d f (,, and d (. The formula 2 2 d 2 4a( d b 4ac b 4* a *( b + 0 (3 d d Therefore, there are real roots for the formula (2. Snce x and ( s the selecton robablty for WLA, the formula (2 and (3 shows that the model can select WLA for transmsson. 3.3 Dual-bandwdth Data Path Desgn The Dual-bandwdth data ath s desgned to get hgher data rates and utlze the two network resources. Snce no sngle network can rovde the moble users fast seed and wde coverage, t s necessary for 4G wreless moble Internet networks to ntegrate current exstng networks. However, ths knd of ntegraton can be based on any two overlang network areas. When a moble node comes nto the overlang area, both networks can rovde servces for the moble node smultaneously. In our roosed soluton, data request can be sent from one of the networks (.e. CDA

6 and rely can be receved from the other network (.e. WLA Dual-bandwdth Data Path odel In order to desgn Dual-bandwdth data ath, we ssue the model. The model desgn s based on WLA and CDA2000 two networks overlang area. When a moble node comes nto the overlang area, WLA and CDA2000 networks are servng for the moble node smultaneously. Data requests are sent from CDA2000 network, and reles are receved from WLA network (see Fgure 3-3. In ths model, the request goes through the frst connecton ( BS PDS C and the resultng rely comes from the second connecton (C PDS AP. Thus, two networks rovde servces for the moble node smultaneously. HA C PDS AP BS Fgure 3-3: Dual-bandwdth Data Path odel Dual-bandwdth Data Path Desgn The comonents of the Dual-bandwdth data ath mlementaton are shown n Fgure 3-4. There are four comonents whch are bandwdth management, bandwdth selecton, acket recever and bandwdth montor. The functon of bandwdth 3-6

7 management s to nstall and delete bandwdth montor comonents dynamcally when t receves ndcaton messages. The bandwdth management s located at both ends.e. the sender and the recever. On each ath, there s one bandwdth montor nstalled. The functon of bandwdth montor s to montor the avalable bandwdth and calculate the roer transmsson rates on the corresondng ath. The current exstng ath s nformed by the bandwdth management after nstallng/deletng each bandwdth montor. The bandwdth montor wll rovde the rates nformaton when t receves the current exstng ath nformaton from bandwdth management. The functon of the bandwdth selecton s to calculate and reort encodng rates to encoder, and then alcatons wll be encoded to arorate aths. The ackets recever accets ncomng ackets from the bandwdth montor, flters and reorders them before sendng them to the decoder. A detaled descrton on each of these four modules s gven n the followng sub-sectons Bandwdth anagement Our Dual-bandwdth data ath mlementaton s based on the WLA and CDA2000 networks. WLA network s mlemented to cover small area, whereas CDA2000 network s mlemented to cover wde area. Both of them have dfferent bandwdth, data rates and cost. Therefore, bandwdth management comonent s needed for mlementng bandwdth selecton n the Dual-bandwdth data ath archtecture. Durng the bandwdth selecton, the bandwdth management wll erform the followng two oeratons: Frstly, the bandwdth management nstalls bandwdth montor for the new 3-7

8 bandwdth ath, and then t sends a RATE_READY message to the local sender/recever to ndcate the exstence of new bandwdth when moble IP reorts a new locaton wth PATH_ADD message; Fgure 3-4: Dual-bandwdth Data Path The bandwdth management wll delete the bandwdth montor and send a RATE_DEL message to the local sender/recever to ndcate that an exstng bandwdth s lost when the moble IP reorts a loss of new locaton wth PATH_LOSS message. Both tyes of bandwdth ndcaton messages (.e RATE_READY and RATE_DEL contan a unque PATH_ID to dentfy the bandwdth to a moble node. To allow a sender to be able to mantan two bandwdths smultaneously, moble IP 3-8

9 smultaneous bndng and route otmzaton otons are used Bandwdth Selecton Bandwdth selecton s only located at the sender sde. Snce WLA has been ntegrated nto CDA2000 networks, the message exchange s needed between both networks. In ths case, the bandwdth selecton calculates and reorts the encodng rates to the encoder so that t can adat ts encodng rates accordngly after the bandwdth selecton receves the bandwdth exstence nformaton from the bandwdth management and the rate nformaton from the bandwdth montor. The bandwdth selecton s also resonsble for assgnng bandwdth encoded alcaton Bandwdth ontor We have stated earler that the functon of bandwdth montor s to calculate the roer transmsson rates and montor acket flows on the corresondng ath. The bandwdth montor s located at both the sender and the recever on each bandwdth ath whch s nstalled by the bandwdth management. The sender and the recever reorts are exchanged between the sender and the recever. In ths case, the sender generates a reort to udate the rate control nformaton and the recever generates a reort for the controlled ath n order to observe congeston status to the sender. The rate control nformaton of the reort ncludes the ath ID so that t can be drected to the corresondng bandwdth montor Packets Recever Packets recever s located at the recever sde only. The functon of ackets recever 3-9

10 s to buffer and reorder all the ackets receved from both bandwdth montor. It s also resonsble to flter out the redundant ackets before delverng them to the target alcaton. In order to establsh and manage the Dual-bandwdth data ath, we roose Bandwdth Otmzaton Control Protocol (BOCP whch wll be dscussed n the followng secton. 3.4 Bandwdth Otmzaton Control Protocol Desgn Desgnng the bandwdth otmzaton control rotocol s a challengng task due to the followng factors: oble Internet rotocol s a basc rotocol runnng on the future 4G wreless moble Internet networks. The moble IP assgns IP address on moble nodes accordng to ts locaton nformaton, whch related wth locaton management, and the bandwdth otmzaton control rotocol desgn s based on two network bandwdth utlzaton. Ths s very dffculty to math the current moble Internet rotocol; and Dual-bandwdth data ath for 4G wreless moble Internet works s based on the ntegraton of WLA-CDA2000 network resources. To establsh a data connecton between the two networks, the bandwdth otmzaton control rotocol desgn s a bg challenge. In order to establsh the Dual-bandwdth data ath, we roose the bandwdth otmzaton control rotocol whose desgn s based on both the locaton management and the network resources management. 3-0

11 The current exstng locaton nformaton management technques can be classfed nto two categores: etwork layer management technques; and Transort layer management technques. The man obectve of most of the network layer locaton management technques was to reduce re-routng acket loss. The transort layer locaton management technques were roosed to get relable data transmsson. Both the network layer management technques and transort layer management technques are not nvolved n the bandwdth utlzaton under the ntegraton of WLA-CDA2000 networks. WLA s oeratng n 2.4GHz frequency band whch can suort a maxmum data rate of b/s or 54b/s about ts standard 802.b and 802.g resectvely [82. As local area coverage, WLA technologes can acheve a hgher data rate at a very low cost and therefore are now wdely mlemented n hotels, restaurants, shong malls, homes etc. On the other hand, for a wde area coverage, the CDA2000 network s wdely mlemented but wth moderate data rate. These two networks are ncomatble but allowng these networks to comlement each other s an added advantage. Possble soluton that we have roosed s to otmze the network resource usage by allowng moble devces full access to both networks smultaneously. Accordng to Lucent research result, t s found that the Internet characterstcs n bandwdth utlzaton that relates to request amounts to one fourth of the rely [83. WLA bandwdth s much hgher than cellular network. Our research 3-

12 s to allow moble node sendng request through CDA2000 network and gettng rely from WLA network by Dual-bandwdth data ath. The bandwdth otmzaton control rotocol desgn s to establsh the Dual-bandwdth data ath, whch s based on the ntegrated archtecture of CDA2000-WLA networks as resented n Fgure GPP2, a standard organzaton has ssued the ntegrated archtecture of WLA and CDA2000 networks, n whch a new comonent has been added n. The new comonent, Packet Data Interworkng Functon (PDIF s between the access ont and the Internet networks [64. The functons of the PDIF have been secfed as followng: Securty gateway; IP connectvty; User authentcaton; Secure tunnel management; Polcy Enforcement; and Accountng Two of the PDIF functons.e. the IP connectvty and user authentcaton related wth our research. The bandwdth otmzaton control rotocol s desgned to use the PDIF functons to manage the Dual-bandwdth. In the case, the alcaton requests wll be managed by PCF (Packets Control Functon n CDA2000 network and the rely wll be controlled by PDIF n WLA network. The bandwdth connecton s rerouted through PDS from CDA2000 network to WLA network. 3-2

13 HLR 4 PST BS PCF SC/VLR HA PDS AAA 2 ITERET AP PDIF 3 Fgure 3-5: CDA2000-WLA Convergence etwork Archtecture [64 The bandwdth otmzaton control rotocol (BOCP s mlemented n between AC layer and TCP/IP layer. An llustratve examle of the functonalty of BOCP consstng of BOC (Bandwdth Otmzaton Control and BOCA (Bandwdth Otmzaton Control Agent comonents s resented n Fgure 3-6. Packets receved from hgher layer are aggregated to BOC. The BOC s defned to resonse for generatng, sendng out and recevng BOCP messages and subsequently usng receved udates to udate the relevant routng tables n our smulaton model. The BOCA s a comonent whch holds nformaton about drect lnk nterfaces of one node and nterfaces of other nodes assocated wth the BOCP. Fgure 3-4 shows that ackets are assgned from network layer to AC layer by 3-3

14 BOC and BOCA comonents. Thus, the basc desgn choces are below: When and where to erform ackets assgnment; Whch ackets are selected for assgnment. Asyncoronous Data/Alcaton TCP(UDP/IP Interface (BOC/BOCA D ata L n k L ayer P h yscal L ayer A C S u b L ayer P L C P S u b layer P D S u b layer Fgure 3-6: BOCP Overvew 3.5 Functonalty of the BOCP Desgn 3.5. BOCP Packets Selecton and Assgnment Fgure 3-7 llustrates the rocessng of ackets from the network layer to data lnk layer for transmsson. The rocessng ncludes ackets selecton and assgnment. In the BOCP, we consder that the selecton of ackets s n strct order receved from network layer. Packets from the network layer are enqueued n order. Frst n Frst out (FIFO algorthm s selected to ensure strct orderng. Ths nvolves an 3-4

15 teratve oeraton that wll frst select the acket at the head of the queue for transmsson rearaton. Then the next acket n the queue wll be selected. If the destnaton address of the acket s the same as the destnaton address of the current workng frame, the acket s aggregated wth the current set. Ths selecton rocess terates untl condton s false. The aggregated collecton of ackets s then encasulated nto the WLA frame for transmsson. Fgure 3-7: etwork Layer and Data Lnk Layer for BOCP After the acket s selected, t wll be queued to nterface for sendng out. In the Fgure 3-7, t shows that the BOCA has a drect lnk nterface whch s used to send BOCP messages after the messages generated by BOC. The BOCP messages wll be sent through the BOCA. In order to do ths, the BOCA needs to have a lst of nodes 3-5

16 nterfaces and ther drect neghbors so that t can generate a correct BOCP message. Any ackets that need to be sent out wll be generated by the BOC. In addton, the BOC wll also receved BOCP messages and subsequently usng receved udates to udate relevant routng tables. Thus, the necessary BOCP messages are generated by BOC, and then dsatched them to a correct destnaton BOCP Defnton and Assumton The BOCP s mlemented usng Java etwork Smulator (ns2 ava verson [84. The Java etwork Smulator (JS allows develoer of networkng rotocols to smulate ther rotocols n a controlled envronment. Several assumtons are necessary to lmt the scoe of our research. The ntent of these lmtng assumtons s to kee the smulaton comlexty manageable, whle stll meetng the research goals. Fgure 3-8: CDA2000-WLA Integrated etwork Comonents 3-6

17 The focus of ths research s the 4G wreless moble Internet to rovde data servces nsde the ntegrated CDA2000-WLA network. Therefore, the voce servce, crcut swtched doman shown n the Fgure 3-5 s not consdered. Thus, the man system comonents of the CDA2000-WLA acket doman archtecture are remodeled as n Fgure 3-8. The archtecture conssts of the moble node (, the base staton (BS, the acket control functon (PCF, the Packet data servce node (PDS, the access ont (AP, and the acket data nterworkng functon (PDIF. The moble node can be a handset, a lato, a ersonal dgtal assstant, etc. We assume that these devces can have full TCP/IP rotocol suort wth data and multmeda alcaton runnng. The base staton (BS and the access ont (AP rovde rado nterface and rado lnk management functonalty for the moble node. These devces rovde connectvty to acket control functon (PCF and acket data nterworkng functon (PDIF resectvely. The acket data servce node (PDS rovdes IP nterface to the Internet. For sesson management and rado resource management, we assume that the CDA2000 connecton s already establshed under the overlang area, and the WLA rado resource s avalable for settng u a new connecton BOCP Assocaton The BOCP assocaton s ntated between the moble node and the base staton or the access ont. Certan BOCP frame s used to ntate the BOCP assocaton. The BOCP frame s based on the defned WLA data frame tyes n secton and 3-7

18 conforms to IEEE 802. requrements [53. Wthn the AC Header, the frst two octets defne Frame Control (FC feld as shown n Fgure frame structure. The Frame Control feld conssts of the followng subfelds: Protocol Verson, Tye, Subtye, To DS, From DS, ore Fragments, Retry, Power anagement, ore Data, Wred Equvalent Prvacy (WEP, and Order. The format of the Frame Control Feld s llustrated n Fgure 3-9. B0 B B2 B3 B4 B7 B8 B9 B0 B B2 B3 B4 B5 Protocol Verson Tye Subtye To DS From DS ore Frag Retry Pwr gt ore Data WEP Order Fgure 3-9: IEEE 802. Frame Control Feld [53 Wthn the Frame Control Feld, there are Tye and Subtye subfelds. The Tye feld s 2 bts n length, and the Subtye feld s 4 bts n length. The Tye and Subtye felds together dentfy the functon of the frame. There are three frame tyes: control, data, and management frames. Each of the frame tyes has several defned subtyes. In the AC header, as shown n Fgure Frame Structure and Fgure Frame Control Feld, the followng tems are related secfcally to our BOCP rotocol: Tye/Subtye feld: Tye/Subtye felds wll be used to ndcate that ths frame s a BOCP frame. The tye feld wll be set to the revously reserved value (, and the subtye (0000- wll be used to ndcate any of the acceted data frames; Duraton/ID feld: Immedately followng the Frame Control feld n the IEEE 802. AC header s the Duraton/ID feld. The Duraton/ID feld s 3-8

19 also 6 bts n length. The contents of ths feld that relates to our research are as follows: o In the subtye frames, the Duraton/ID feld carres the assocaton dentty (AID of the staton that transmtted the frame n the 4 least sgnfcant bts (lsb, wth the 2 most sgnfcant bts (msb both set to. The value of the AID s n the range of to 2007; o In all other frames, the Duraton/ID feld contans a duraton value as defned for each frame tye. For frames transmtted durng the contenton-free erod (CFP, the duraton feld s set to Frame Check Sequence (FCS: FCS wll be comuted over the entre aggregate header. Therefore, we assume that durng assocaton between the PDIF and AP, t s necessary for an assocaton request frame to suort our BOCP enhancement by settng the frst 5 bts (.e. bt from B0 to B4 of the caablty nformaton feld shown n Fgure 3-0. Ths frame s transmtted by the PDIF to AP n order to ntate assocaton. The AP wll resond wth an assocaton resonse frame. The AP wll use the same frst 5 bts n the caablty nformaton feld to declare ts ablty to suort the BOCP. B0 B B2 B3 B4 B5-B5 ESS IBSS CF Poll able CF Poll request Prvacy Reserved Octets: 2 Fgure 3-0: WLA Caablty Informaton Feld [53 3-9

20 3.5.4 BOCP Frame Format The BOCP frame format s shown n Fgure 3-. The followng tems are secfc to our BOCP: command ( verson ( Routng Doman (2 Address Famly Identfer (2 Route Tag (2 IP Address (4 Subnet ask (4 ext od (4 20 bytes etrc (4 Fgure 3-: Format of BOCP message [53 Command feld defned message tye and subtye of request or resonse. Tye/Subtye felds exlaned earler wll be used to ndcate that ths frame s a BOCP frame; Routng Doman feld wll be used to ndcate that moble nodes of one routng rocess can be located n both WLA and CDA2000 domans; and ext od feld s set to IP address of the next node along the way. As we have resented n secton 3.2, the necessary BOCP messages are generated from all nodes to all ther neghbors. Therefore, ths feld s used to ndcate the moble node neghbor s IP address. The other frame felds are used to ndcate the same functonalty as exlaned n [53:. Verson s set to be 2;. Address Famly Identfer for Internet networks s always 2 for IP; 3-20

21 . v. Route Tag rovdes suort for EGPs; Subnet ask ndcates the destnaton subnet mask (all s for host address; and v. etrc wll be used to count node number of the secal routng. 3.6 Performance etrcs on BOCP Desgn The BOCP s evaluated based uon throughut and buffer requrement. Therefore, the throughut and buffer requrement are two man metrcs for evaluatng the BOCP erformance. The two metrcs are defned as follows: 3.6. Throughut The CDA2000 network and WLA are two dfferent networks wth dfferent technologes and bandwdth. The WLA bandwdth s much wder than CDA2000 network. Regardng the bandwdth dsarty, we establsh the Dual-bandwdth data ath for utlzng the two network resources to get hgher throughut by mlementng the BOCP. Thus, throughut can be used to evaluate the erformance of ths ntegraton. In communcaton networks, throughut s the amount of dgtal data er tme unt that s delvered over a hyscal or logcal lnk, or that s assng through a certan network node. For examle, t may be the amount of data that s delvered to a CDA2000 network moble node or a WLA network moble node, or between the two moble nodes. The throughut s usually measured n bts er second (bts/s or bs and occasonally n data ackets er second. Relatve to our research, throughut s defned as the total number of bts sent to the network layer from the data lnk layer. 3-2

22 The data ackets receved at the hyscal layer are sent to the hgher layer f they are destned. We measured ths value n terms of bts er second. Throughut reresents an average rate of traffc flow where hgher values are better Buffer Requrement As we have shown n Fgure 3-4, the Dual-bandwdth data ath was roosed and the buffers are requred for the Dual-bandwdth data ath. Accordng to ITU (Internatonal Telecommuncaton Unt standards, for a non-real-tme Internet sesson, the buffer tme, B, s defned as the length of tme that the ackets are released from t the exstng route to a new route whch s establshed and ths s calculated as follows [85: B ( t R t (C, Durng the course of the establshng the Dual-bandwdth data ath, the alcaton ackets were transmttng from C to, usng any two nodes dstances by the ackets rate to calculate the buffer tme for the moble IP ackets whch s from C to. R t ( C, In the formula above, one can denote the buffer tme as whch s shown n (. Ths reresents the tme that the controlled-load traffc s buffered by C. Then, the requred buffer sze, B B * P s (2 P b * P r r t (3 r s B s, s calculated as follows: From the formula, the buffer sze ( B s equal to buffer tme ( B tmes wth s acket rate ( P r, and the acket rate ( P r s equal to bt rate ( b r tmes wth the acket sze ( P s. Thus, we can get buffer sze ( B s as follows: t 3-22

23 B B * b * P s (4 t r s BOCP Evaluaton Technques Generally, there are three ossble technques of erformance evaluaton used n research, whch are analytc, smulaton, and measurement [86. The selecton of a artcular evaluaton technque deends on whether t can sgnfcantly mact the outcome of a erformance evaluaton. These methods dffer n terms of accuracy, cost, and requred tme. We choose smulaton to conduct ths erformance analyss due to lmtatons n avalable resources BOCP Smulaton Parameters We have develoed a smulaton envronment to evaluate our roosed archtecture. Smulaton arameters for our smulaton model are based on the values that accurately modeled the archtecture roosed by 3GPP2. These smulaton matrces are gven n Table

24 Smulaton Parameters Descrtons Values PDIF Functonalty Ths value secfed whether the Packet Data Interworkng Functon s enabled for the WLA AC. Enabled AP Functonalty WLA Physcal Layer Characterstcs WLA Data Rate CDA2000 x-evdo Cell State Ths value secfed whether the access ont s enabled for the WLA-AC. The value of ths attrbute determned the hyscal layer technology n use. Ths value secfed the data rate that s used by the AC for the transmsson of the data frames va the hyscal layer. Ths value ndcated that all CDA2000 x-evdo ulnk and downlnk traffc s sent on data control channels (DCCH. Table 3-: BOCP Smulaton atrces Enabled Drect Sequence bs DCCH PDIF Functonalty 3GPP2 has secfed the functonaltes of acket data nterworkng functon (PDIF. These functonaltes have been resented earler n ths chater. Ths value secfed whether the Packet Data Interworkng Functon s enabled for the WLA-AC AP Functonalty WLA access ont s a general comonent n ts network whch s used to assgn user request and rely. Ths value secfed whether the access ont s enabled for the WLA-AC [ WLA Physcal Layer Characterstcs The smulaton s run wth the WLA hyscal layer characterstcs set to Drect 3-24

25 Sequence Sread Sectrum (DSSS. The value of ths attrbute determned the hyscal layer technology n use WLA Data Rate Followng the IEEE 802.b standards, we set WLA data rate to bs. Ths value secfed the data rate that s used by the AC for the transmsson of the data frames va the hyscal layer CDA2000 x-evdo Qualcomm s roretary HDR (Hgh Data Rates technology dedcates a x carrer for fast data use only. Ths s called xev DO (Data Only. CDA2000 xev-do s secfed n 200 by 3GPP2, whch ntroduces a new ar nterface and suorts hgh data rates servce for downlnk [64. It requres a searate.25 Hz carrer for data only, but the seed can be u to 3. bs on the downlnk. Data transmsson on sulemental channel s suorted. Ths value sets for the smulaton arameter ndcates that all CDA2000 x-evdo ulnk and downlnk traffc are sent on the data control channels (DCCH BOCP Smulaton Scenaro The smulaton s runnng under the scenaro termed a dual mode moble node access CDA2000-WLA convergence archtecture of 3GPP2. The smulaton model of the network s shown n Fgure

26 Fgure 3-2: Smulaton Scenaro odel The rmary focus of the scenaro s the two access network used smultaneously for the moble node. When the moble node comes nto the WLA overlang regon from the CDA2000 coverage area, the request wll go through the frst connecton ( BS PCF PDS C and the resultng rely wll come through the second connecton (C PDS PDIF AP. The scenaro smulated a moble node runnng the BOCP on the ntegrated CDA-WLA network. The urose of the smulaton s to exercse the ntegrated system over the new rotocol to demonstrate system data rates BOCP Smulaton Desgn The ratonale and the overvew of the smulaton-based exerments emloyed to evaluate the BOCP enhancement wll be dscussed n ths secton. The results and analyss from each of those smulatons wll be dscussed n the next chater. We used 3-26

27 JS standard models and modfed them to suort our BOCP. The man classes such as BOC class, BOCA class, BOCPessage class, obleode Class, Route Class and RoutngTable class are desgned as followng. Other suorted classes such as QueueLst class, RouteAlreadyInRoutngTableExceton class, etc. are not lsted but can be found n attachment BOC Class The BOC class s resonsble for generatng BOCP messages and sendng them to the correct destnatons. It s also resonsble for recevng the udates and usng them to udate the relevant routng table. At ths stage t s necessary to take the decson of whether to have a global (statc BOC class. The global BOC class would be resonsble for sendng out udates from nodes and udatng the routng tables of all the nodes n the smulaton network. The BOC class actvty dagram s resented n Fgure 3-3 where t shows that the BOC class generates BOCPessages for all node nterfaces. The BOCPessages wll be used to udate arorate routng tables. Once all the BOCPessages have been sent out and all the routng tables have been udated, the BOC class wll lace a new command n the smulator queue for stong or contnung the actvty. The BOC class wll accomlsh ts tasks by makng use of the global nformaton avalable n the BOCA class. 3-27

28 Fgure 3-3: Actvty dagram for the BOC class 3-28

29 BOCA Class In the smulaton network, we are nterested wth the drect lnk nformaton snce n BOCP a moble node wll need to send data to ts drect lnk neghbor only. Hence t s necessary to have a lst of node nterfaces and ther drect neghbors n order to generate the correct BOCP routng udate messages. Therefore, the BOCA class needs to have nformaton about the nterfaces assocated wth a artcular node and kee track of what s lnked to what n the smulaton network (see Fgure 3-4. Fgure 3-4 shows the BOCA class hash table. The ndex of the array reresents the nterface of a node and t wll be stored n the hash table.e. gven a router nterface, one could retreve from the hash table the ndex of the array whch contans lnks to that nterface. From the BOCA class hash table, a reference to a vector wll be stored at that ndex and ths second-dmensonal vector wll hold all the nterfaces that the router nterface s drectly lnked to. An array has been chosen for the frst dmenson because once a network has been set u t wll not be necessary to add new nodes very often. In fact, n the smulator rogram at resent, once a network has been set u and the smulaton starts, t s not ossble to add new nodes to the network. In the hash table, the nformaton about the nterfaces assocated wth artcular nodes wll be stored as a moble nodes obect. The BOCA class has a Vector contanng references to the moble node obect. The moble node obect wll then be occurred as nstance varables n the BOCA class. The beneft of usng hash table for the BOCA class s that t would save retreval 3-29

30 tme and therefore be more effcent. In order to reduce the retreve tme, the data retreved from the hash table need not to check table tems one by one. It needs to check the node nterface and then for the node nterface 2 n the hash table. Fgure 3-4: The BOCA Class Hash Table BOCPessage Class The BOCPessage holds the necessary nformaton to udate a obleode s routng table accordng to BOCP. The class contans man nformaton as followng: The frst s a obleode nterface from and to whch ths BOCPessage wll be sent; The second s the smulator tme of ths udated; and The thrd s vector contans BOCPessage obect references. The functonalty of ths class s to defne what wll be sent from a certan node to ts neghbor n order to udate the routng tables of the neghbor. Ths s the 3-30

31 Route that wll be chosen to be sent to that artcular neghbor. After the BOCPessage verfed ts route, then the route can reach destnaton. A Vector as a lnear data structure s sutable to hold the Route obects. We created the class of RouteAlreadyInRoutngTable to deal wth ths obleodes Class The obleode class contans a node and the nterfaces assocated wth that node. The BOC class has a vector as an nstance varable whch contans references to the obleode obect Route Class The Route class holds nformaton about whch nterface to send ackets out for a artcular destnaton together wth the IP addresses of ts neghbors. Ths class wll be modeled on the re-exstng Route class found n JS, but wll requre some modfcaton for comatblty wth BOCP RoutngTable Class The RoutngTable class s used to store the route obects. Ths class s modeled on the re-exstng RoutngTable class from JS. The data structure of the class s hash table (see Fgure 3-4. Ths would be more effcent when udatng routes snce t s not needed to go through the whole routes lookng for the one for udates. 3.7 Conclusons In ths chater, we have roosed a concetual desgn of Dual-bandwdth data ath at 3-3

32 CDA2000 and WLA networks. In order to establsh the Dual-bandwdth data ath between the two networks under the ntegrated archtecture of CDA2000-WLA, we roosed the Bandwdth Otmzaton Control Protocol. BOCP s desgned for the Dual-bandwdth data ath. Data transmsson on the Dual-bandwdth data ath s controlled and managed by the BOCP. Thus, ths chater roosed two desgns, the Dual-bandwdth data ath desgn and the BOCP desgn. In order to desgn BOCP, we have defned the functonaltes of the BOCP ncludng the BOCP ackets selecton and assgnment, the BOCP acket defnton and assumton, the BOCP assocaton and the BOCP frame format. The erformance metrcs on BOCP desgn has been defned whch are ncludng the BOCP evaluaton technques, the BOCP smulaton arameters, the BOCP smulaton scenaro and the BOCP smulaton desgn. In order to rove the Dual-bandwdth data ath and BOCP desgn, the system smulaton wll be resented n the followng chater