i hc Quc gia Thnh ph H Ch Minh

Trng i hc Cng Ngh Thng Tin

Tm hiu v JADE (Java Agent Development Framework)

Hc k: VI Lp: CNTN02 Mn hc: Tr tu nhn to nng cao Ging vin hng dn: ThS. Nguyn Trn Minh Khu Thc hin: Nguyn Hu Vit Long 07520205 Hong Linh 07520

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1. CNG NGH AGENT

1.1. nh ngha: 1.1.1.Agent: Theo Wooldridge v Jennings (hai gio s ni ting ngnh Khoa hc my tnh ca hai trng i hc ln Anh l University of Liverpool v School of Electronics and Computer Science at

Southampton University): Agent (tc t) l mt h thng tnh ton (my tnh) c kh nng t ch hnh ng vi t cch i din cho mt ai (tm ra cc cch thc hon thnh mc tiu thit k hn l ch nht nht lm theo nhng g c ch bo)

Gio s Michael Wooldridge

1.1.2.Multi-agent:

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Multi-agent l mt h thng gm nhiu agents c th tng tc vi nhau bng cch trao i cc thng ip thng qua h tng mng my tnh. tng tc thnh cng, cc agents phi c cung cp kh nng cng tc (cooperate), phi hp (coordinate) v dn xp (negotiate) vi nhau. 1.2. Tnh cht: Tnh phn x Tnh t ch ng Tnh cng ng Kh nng t hc Tnh thch nghi Kh nng di chuyn 1.1. The Foundation for Intelligent, Physical Agents (FIPA) FIPA l mt t chc phi li nhun, thnh lp nm 1996. y l thnh vin ca IEEE Computer Society, n cung cp, ci tin cc cng ngh trn c s Agent, Multi-agent v tch hp n vi cc cng ngh khc. Ngy nay FIPA c 65 cng ty thnh vin trn ton th gii Website chnh thc ca FIPA: http://www.fipa.org/ 2. JADE PLATFORM 2.1. Lch s JADE JADE c pht trin ln u bi Telecom Italia vo khong cui nm 1998 v c thc y pht trin bi mong mun cng b nhng k thut, tiu chun u tin, s khi ca FIPA JADE tin ti tr thnh m ngun m vo nm 2000 vi giy php LGPL (Library Gnu Public Licence). 2.2. Tng quan v JADE JADE (Java Agent Development Framework) l mt nn tng phn mm gip cho vic pht trin cc ng dng agent d dng hn, n cung cp c bn lp trung (middleware-layer) cc chc nng m khng ph thuc vo ng dng c th v gip n gin ha vic thc hin pht trin cc ng dng khai thc cc phn mm Agent (Theo Wooldridge v Jennings) JADE hon ton hng i tng, s dng ngn ng Java v c pht trin trn nn tng m ngun m. Phin bn mi nht ca JADE l JADE 4.0 cng b ngy 20-04-20102.3. Kin trc ca JADE:

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JADE platform l kt hp ca cc Agent Containers c th pht trin thng qua mng Internet. Cc Agents c ng trong cc Containers l cc tin trnh Java cung cp JADE run-time v tt c dch v cn thit cho vic hosting v thc hin cc Agents. C mt container c bit, gi l main container, biu din bootstrap point ca mt platform: n l container u tin c ni ti v tt c containers khc phi tham gia vo mt main container bng cch ng k vi n. Main container mt s chc nng c bit sau:

Qun l container table (CT), dng cha cc thng in ng k ca cc i tng tham chiu v a ch lun chuyn ca tt c cc container nodes kt hp trn mt platform Qun l Global Agent Descriptor Table (GADT), cha cc thng tin ng k ca tt c Agents trn platform, bao gm trng thi hin ti v v tr ca chng Hosting AMS v DF, hai Agents c bit cung cp b qun l Agent, white page service v yellow page service mc nh ca platform.

JADE platform tun theo cc tiu chun ca FIPA cho cc h thng a tc t thng minh. Mc ch ca JADE l n gin ha vic pht trin m vn m bo tun th cc tiu chun thng qua 1 tp hn hp cc dch v h thng v cc tc t. t c mc ch ny, JADE a ra 1 danh sch cc tnh nng cho ngi lp trnh agent: Tiu chun FIPA v nn tng Agent (FIPA-compliant Agent Platform), bao gm h thng qun l Agent AMS (Agent Management System), DF (Directory Facilitator) v knh thng tin agent ACC (Agent Comunication Channel). C 3 agent u c kch hot t ng ngay khi khi ng nn tng agent ny. Nn tng agent phn tn. Nn tng agent ny c th c phn chia trn 1 vi my ch (vi iu kin khng c tng la gia chng). Ch c 1 ng dng c thc thi trn mi my ch v ch c 1 my o Java. Cc agent c thc thi nh 1 lung Java v cc s kin Java c dng nng cao hiu sut v gim nh gnh nng lin lc gia cc agent4

trn cng 1 host. Cc tc v song song c th c thc thi bi 1 agent, v JADE lp lch cho cc tc v ny 1 cch hiu qu hn my o Java thc hin cho 1 lung (thm ch c th n gin hn i vi ngi lp trnh tt). Mt s DFs (Directory Facilitator) chun FIPA c th c khi ng khi ang chy chng trnh thc thi cc ng dng a min, ni m khi nim min (domain) l 1 khi nim logic nh c m t trong phn 1 FIPA97. Lp trnh giao din n gin ha vic ng k ca 1 dch v agent vi 1 hay nhiu min (domain).

C ch truyn ti v giao din cho vic gi / nhn thng ip i / n cc agent khc Dng giao thc IIOP chun FIPA97 kt ni cc nn tng agent khc nhau S truyn ti nh nhng ca cc thng ip ACL bn trong cng nn tng agent th tt hn cc chui, hn na c th trnh cc th tc ghp ni, v cc thng ip ny c m ha nh cc i tng Java. Th vin ca cc giao thc tng h FIPA lun sn sng s dng. Giao din ha ngi dng qun l cc agent trong cng 1 agent. Hot ng ca mi nn tng (platform) c th c theo di v ghi li. Ton b vng i hot ng ca cc agent (to mi, treo hay kt thc 1 agent ang tn ti,...) c th c thc hin thng qua giao din qun l ny.

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M hnh UML trnh by khi qut mi quan h gia cc phn t kin trc chnh ca JADE

1.1. Message transport service Message transport service (MTS) l mt trong ba dch v quan trng m mt agent platform yu cu (hai dch v cn li l AMS v DF). MTS qun l tt c cc giao tip thng ip bn trong v gia cc platforms1.1.1.Message Transport Protocols

pht trin ng dng giao tip vi cc platforms khc (khng phi l JADE), JADE thc thi tt c Message Transport Protocols (MTPs) c nh ngha bi FIPA. Mi MTP nh ngha mt phng thc vn chuyn v mt chun m ha thng ip Mi thng ip cung cp mt chun xut ra khi kt ni ti mt main container v thng bo tng t nh th ny: INFO: MTP addresses: http://anduril:7778/acc

1.1.2.Internal Message Transport Protocol6

JADE IMTP (Internal Message Transport Protocol) ch c dng khi trao i thng ip gia cc Agents c ng trong cc containers khc nhau ca cng mt platform. Do ch c dng giao tip bn trong cc platform, nn n khng cn ph hp vi mt chun FIPA no. N hon ton c quyn t ch nn thng c thit k gia tng hiu sut platform. JADE IMTP thc ra khng ch c dng vn chuyn cc thng ip m cn vn chuyn cc cu lnh bn trong cn thit qun l platform phn tn. JADE c thit k cho php chn la IMPT ti thi im kt ni vi platform. C hai IMPT chnh: IMPT da trn java RMI l la chn mc nh ca h thng; IMPT da trn mt phng thc s dng TCP sockets, iu ny hn ch s bin mt ca Java RMI trong mi trng J2ME. C hai IMPT ny u cung cp vi la chn v cu hnh cho php iu chnh tt IMPT trong mng ch nh v cc c trng ca thit b 2. KIN TRC NI TI CA JADE 3. TI LIU THAM KHO: Fabio Bellifemine, Giovanni Caire, Dominic Greenwood Developing Multi-Agent Systems with JADE John Wiley & Sons Ltd, 2007 Michael Wooldridge An Introduction to Multiagent Systems John Wiley & Sons Ltd, 2002

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