SECURITY ISSUES IN THE OPTIMIZED LINK STATE ROUTING PROTOCOL VERSION 2 (OLSRV2)

Transcription

1 SECURITY ISSUES IN THE OPTIMIZED LINK STATE ROUTING PROTOCOL VERSION 2 (OLSRV2) Ulrih Hererg n Thoms Clusen Hiperom@LI, Eole Polytehnique, Frne ulrih@hererg.nme, thoms@thomslusen.org ABSTRACT Moile A ho NETworks (MANETs) re leving the onines o reserh lortories, to in ple in rel-worl eployments. Outsie speilize omins (militry, vehiulr, et.), ity-wie ommunitynetworks re emerging, onneting regulr Internet users with eh other, n with the Internet, vi MANETs. Growing to enompss more thn hnul o truste prtiipnts, the question o preserving the MANET network onnetivity, even when e with reless or mliious prtiipnts, rises, n must e resse. A irst step towrs proteting MANET is to nlyze the vulnerilities o the routing protool, mnging the onnetivity. By unerstning how the lgorithms o the routing protool operte, n how these n e exploite y those with ill intent, ountermesures n e evelope, reying MANETs or wier eployment n use. This pper tkes n strt look t the lgorithms tht onstitute the Optimize Link Stte Routing Protool version 2 (OLSRv2), n ientiies or eh protool element the possile vulnerilities n ttks in ertin wy, provies ookook or how to est ttk n opertionl OLSRv2 network, or or how to proee with eveloping protetive ountermesures ginst these ttks. KEYWORDS OLSRv2, MANET, Vulnerility Anlysis, Seurity 1. INTRODUCTION OLSRv2 (the Optimize Link Stte Routing Protool version 2) [1], [2], [3], [4], [5] is suessor to the wiely eploye OLSR [6] routing protool or MANETs (Moile A ho NETworks). OLSRv2 retins the sme si lgorithms s its preeessor, however oers vrious improvements, e.g. moulr n lexile rhiteture llowing extensions, suh s or seurity, to e evelope s -ons to the si protool. The evelopments relete in OLSRv2 hve een motivte y inrese rel-worl eployment experienes, e.g. rom networks suh s FunkFeuer [7], n the requirements presente or ontinue suessul opertion o these networks. With prtiiption in suh networks inresing (the FunkFeuer ommunity network hs, e.g., roughly 400 iniviul prtiipnts), operting with the ssumption, tht prtiipnts n e truste to ehve in non-estrutive wy, is utopi. Tking the Internet s n exmple, s prtiiption in the network inreses n eomes more iverse, more eorts re require to preserve the integrity n opertion o the network. Most SMTP-servers were, e.g., initilly ville or use y ll n sunry on the Internet with n inrese popule on the Internet, ttks n uses use the reommene prtie is toy to require uthentition n ounting or users o suh SMTP servers [8]. A irst step towrs hrening ginst ttks isrupting the onnetivity o network, is to unerstn the vulnerilities o routing protool, mnging the onnetivity. This pper thereore nlyzes OLSRv2, to unerstn its inherent vulnerilities n resilienes. The uthors o not lim ompleteness o the nlysis, ut hope tht the ientiie ttks, s presente, orm meningul strting-point or eveloping seure OLSRv2 networks.

2 1.1. OLSRv2 Overview OLSRv2 ontins three si proesses: Neighorhoo Disovery, MPR Flooing n Link Stte Avertisements, esrie in the elow with suiient etils or elorting the nlysis in ltter setions o this pper Neighorhoo Disovery Neighorhoo Disovery is the proess, wherey eh router isovers the routers whih re in iret ommunition rnge o itsel (1-hop neighors), n etets with whih o these it n estlish i-iretionl ommunition. Eh router sens HELLOs, listing the ientiiers o ll the routers rom whih it hs reently reeive HELLO, s well s the sttus o the link (her, veriie i-iretionl). A router reeiving HELLO rom neighor, in whih inites to hve reently reeive HELLO rom, onsiers the link - to e i-iretionl. As lists ientiiers o ll its neighors in its HELLO, lerns the neighors o its neighors (2-hop neighors) through this proess. HELLOs re sent perioilly, however ertin events my trigger non-perioi HELLOs MPR Flooing MPR Flooing is the proess wherey eh router is le to, eiiently, onut network-wie rosts. Eh router esigntes, rom mong its i-iretionl neighors, suset (MPR set) suh tht messge trnsmitte y the router n relye y the MPR set is reeive y ll its 2-hop neighors. MPR seletion is enoe in outgoing HELLOs. Routers my express, in their HELO messges, their willingness (integer etween 1 will never n 7 will lwys ) to e selete s MPR, whih is tken into onsiertion or the MPR lultion, n whih is useul or exmple when n OLSRv2 network is plnne. The set o routers hving selete given router s MPR is the MPR-seletor-set o tht router. A stuy o the MPR looing lgorithm n e oun in [9] Link Stte Avertisement Link Stte Avertisement is the proess wherey routers re etermining whih link stte inormtion to vertise through the network. Eh router must vertise, t lest, ll links etween itsel n its MPR-seletor-set, in orer to llow ll routers to lulte shortest pths. Suh link stte vertisements re rrie in TCs, rost through the network using the MPR looing proess esrie ove. As router selets MPRs only rom mong i-iretionl neighors, links vertise in TC re lso i-iretionl n routing pths lulte y OLSRv2 ontin only i-iretionl links. TCs re sent perioilly, however ertin events my trigger non-perioi TCs Link Stte Vulnerility Txonomy Proper untioning o OLSRv2 ssumes tht (i) eh router n quire n mintin topology mp, urtely releting the eetive network topology; n (ii) tht the network onverges, i.e. tht ll routers in the network will hve suiiently ientil topology mps. An OLSRv2 network n e isrupte y reking either o these ssumptions, speiilly () routers my e prevente rom quiring topology mp o the network; () routers my quire topology mp, whih oes not relet the eetive network topology; n () two or more routers my quire inonsistent topology mps OLSRv2 Attk Vetors Besies rio jmming, ttks on OLSRv2 onsist o mliious router injeting orretly looking, ut invli, ontrol tri (TCs, HELLOs) into the network. A mliious router n either () lie out itsel (its ID, its willingness to serve s MPR), heneorth Ientity Spooing or () lie out its reltionship to other routers (preten existene o links to other

3 routers), heneorth Link Spooing. Suh ttks will in-ine use isruption in the Link Stte Avertisement proess, through trgeting the MPR Flooing mehnism, or y using inorret link stte inormtion to e inlue in TCs, using routers to hve inomplete, inurte or inonsistent topology mps. In ierent lss o ttks, mliious router injets ontrol tri, tune to use n in-router resoure exhustion, e.g. y using the lgorithms lulting routing tles or MPR sets to e invoke ontinuously, preventing the internl stte o the router rom onverging Pper Outline The reminer o this pper is orgnize s ollows: setion 2, 3, n 4 eh represents lss o isruptive ttks ginst OLSRv2, etiling numer o ttks in eh lss. Setion?? summrizes the ientiie vulnerilities in n OLSRv2 network, n setion 6 summrizes inherent resiliene, s oserve in OLSRv2. The pper is onlue in setion TOPOLOGY MAP ACQUISITION Topology Mp Aquisition reltes to the ility or ny given router in the network to quire representtion o the network onnetivity. A router, unle to quire topology mp, is inple o lulting routing pths n prtiipting in orwring t. Topology mp quisition n e hinere y () TCs to not eing elivere to (ll) routers in the network, suh s wht hppens in se o Flooing Disruption, or () in se o jmming o the ommunition hnnel Flooing Disruption MPR seletion (setion 1.1.2) uses inormtion out router s 1-hop n 2-hop neighorhoo, ssuming tht (i) this inormtion is urte, n (ii) ll 1-hop neighors re eqully pt s MPR. Thus, mliious router seeking to ttk the MPR Flooing proess will seek to mnipulte the 1-hop n 2-hop neighorhoo inormtion in router suh s to use the MPR seletion to il Flooing Disruption ue to Ientity Spooing Figure 1() illustrtes network in whih the mliious router (gry irle) spoos the ientity o, i.e. reeives HELLOs rom two routers, oth pretening to e. As HELLOs re itive, n with the mliious router not vertising ny neighors, the topologil view o the 1-hop n 2-hop neighorhoo o is unete y the presene o : s MPR seletion will untion orretly y seleting (i using greey lgorithm). e e spoos () The gry mliious router spoos ress o spoos () The mliious router spoos ress o n vertises link to Figure 1. Ientity Spooing: looing ttk: 1-hop ress uplition. Figure 1() illustrtes network in whih the mliious router (gry irle) spoos the ientity o. In this exmple, link (the otte line) etween n is orretly etete n vertise y. Router will reeive HELLOs initing tht links exist rom to oth e n, therey renering nite MPR on pr with. I oes not orwr looe tri (i.e. oes not ept MPR seletion), its presene entils looing isruption: seleting over reners unrehle y looe tri. In orer to

4 spoos x x Figure 2. Ientity Spooing: looing ttk: 2-hop ress uplition. inrese the likelihoo tht the mliious is selete, it my set its willingess to 7 (mx), ensuring tht it is lwys selete n the routers so overe re not urther onsiere in the MPR seletion lgorithm. Figure 2 illustrtes network in whih the mliious router (gry irle) spoos the ientity o x, i.e. n oth reeive HELLOs rom router pretening to e x. From the point o view o, it ppers s i n hve the sme neighor set, hene either is suitle hoie s MPR. Assuming tht selets s MPR, will not rely looe tri n thus the legitimte (white) x (n routers to the right o x) will not reeive looe tri. In orer to mximize the impt o the isruption, the mliious router my simultneously spoo multiple ientities: y overhering ontrol tri or while, the mliious router my ttempt to lern the ientities o neighors o n spoo these n, in ition, ssume one itionl ientity (possily not otherwise present in the network). A wy o hieving this is to simply hve overher ll TCs, n spoo ll ientities o ll routers in the network (possily exluing ). Router will lern through the HELLOs o tht ll these ientities re 2-hop neighors o. As the set o ientities spooe y the mliious is superset o the neighors o, this will use seletion o s MPR, n onsequently tht is not selete. x spoos x Figure 3. Ientity Spooing: looing ttk: 1 n 2-hop ress uplition. Figure 3 illustrtes network in whih the mliious router (gry irle) spoos the ientity o x, i.e. n oth reeive HELLOs rom router pretening to e x. Router will thereore not selet s MPR s ll the 2-hop neighors rehle vi re lrey rehle iretly in one hop. As onsequene, the white x, n ny routers to the let o it, will not reeive looe ontrol tri rom or trnsite vi rom e.g Flooing Disruption ue to Link Spooing Figure 4() illustrtes network, in whih the mliious router spoos links to the non-existing, i.e. reeives HELLOs rom, pretening the existene o link etween n. This ores to selet s MPR wheres it otherwise woul not nee to selet ny MPRs. In this simple exmple, this oes no hrm s suh. Figure 4() illustrtes network, in whih the mliious spoos links to the existing, s well s to non-existing w. Router reeives HELLO rom reporting links to n w, n rom reporting link to only. Unless i hs vertise willingness o 7, this will use to selet s its only MPR, s presumly overs ll 2-hop neighors o (i.e. the rel neighors o s well s the imginry w). The onsequene is tht s will not selet s MPR, will not rely looe messges reeive rom. Thus, the network to the let o (strting with ) will not reeive ny looe messges rom or trnsiting, suh s messge originting rom s n trnsiting through.

5 s w () Bsi Link Spooing eet on MPR Seletion Figure 4. () Flooing isruption ue to Link Spooing Link Spooing: Flooing Disruption 2.2. Rio Jmming Rio jmming is n ttk in whih legitimte ess to the ommunitions hnnel etween routers is oreully hinere y mliious evie. The lssi exmple hereo is where powerul trnsmitter is generting white noise over the ommunitions hnnel where the network interes o the routers woul otherwise operte, eetively preventing these router interes rom suessully reeiving trnsmissions rom eh other. While this n hppen on ll network intere n hnnel types, wireless networks re espeilly vulnerle to suh; ommeril WiFi jmmers re, or exmple, reily ville [10]. The onsequene o suh jmming is tht the router interes, whih re so jmme, re unle to reeive routing protool ontrol tri, n so re unle to prtiipte in the network. A router where ll its network interes re vitim to jmming is, eetively, unle to quire topology mp o the network n, so, is isonnete rom the network. It n e oserve tht router with multiple network interes essing ierent ommunitions hnnels, n where not ll ommunitions hnnels re jmme, my still e le to prtiipte in network vi links over these non-jmme interes. Figure 5. Rio Jmming: is jmming reeption within the grye-out re, thus is unle to orretly reeive trnsmission. It n lso e oserve tht while iret jmming ets reeption, it my (epening on whih lower lyers L1/L2 re employe) not et trnsmission. Thus, n s illustrte in igure 5,, my reeive trnsmissions rom, the ltter o whih is otherwise jmme y, whih prevents reeptions in the grye re. The Neighorhoo Disovery mehnism o OLSRv2 ientiies uni- n iiretionlity o links, n only i-iretionl links re vertise n use or routing pth lultions. OLSRv2 hs, thus, y virtue o this etetion n use o only i-iretionl links, some resiliene to jmming: while the jmme routers re unle to quire n mintin topology mp o the network, the jmme routers pper s simply isonnete to the un-jmme prt o the network whih is le to oth mintin urte n onsistent topology mps Attk on Jittering OLSRv2 inorportes jittering: rnom, ut oune, ely on outgoing ontrol tri. This my e neessry when link lyers (suh s [11]) re use, whih o not gurntee ollision-ree elivery o rmes, n where jitter n reue the proility o ollisions o rmes on lower lyers is [1].

6 In OLSRv2, TC orwring is jittere y vlue etween 0 n MA_JITTER. In igure 6, router reeives three pkets, eh ontining one TC to e orwre. For eh o these, the sheule retrnsmission time is lulte s now plus jitter, illustrte y the horizontl rrows. In orer to reue the numer o trnsmissions, when ontrol messge is ue or trnsmission, OLSRv2 piggygs ll queue messges into single trnsmission. Thus, i mliious router sens mny TCs within very short time intervl, the jitter time o the ttke router tens to 0. This reners jittering ineetive n n le to ollisions on L2. pket inoming eetive tx time o ll messges sheule tx time time Figure 6. Jittering: I severl messges re sheule to e trnsmitte, ll the messges re sent t the minimum o the sheule trnsmission times Hop-ount n Hop-limit Attks The hop-ount n hop-limit iels re the only prts o TC tht re moiie when orwring. A mliious router n moiy either o these when, when orwring TCs Moiying the Hop Limit A mliious router n erese the hop limit when orwring TC. This will reue the sope o orwring the messge, n my le to some routers in the network not reeiving tht TC. Note tht this is not neessrily the sme s not relying the messge (i.e. setting the hop limit to 0), s illustrte in igure 7. TC TC Figure 7. Hop limit ttk A TC rrives t n is orwre y, suh tht it is reeive y oth n the mliious. n orwr the TC without ny ely (inluing without jitter) suh tht its trnsmissions rrives eore tht o t. Beore orwring, it signiintly reues the hop limit o the messge. Router reeives the TC, proesses (n orwrs) it, n mrks it s lrey reeive - using it to isr urther opies reeive rom. Thus, i the TC is orwre y, it hs very low hop limit n will not reh the whole network Moiying the Hop Count A mliious router n moiy the hop ount when orwring TC. This my hve two onsequenes: (i) i the hop ount is set to the mximum vlue, then the TC will e orwre no urther y, or (ii) rtiiilly mnipulting the hop ount my et the vliity time s lulte y reipients, when using istne-epenent vliity times s eine in [3] (e.g. s prt o ish-eye extension to OLSR2 [12]).

7 TC v_time(3hops): 6s v_time(2hops): 4s v_time(1 hop): 2s Figure 8. Dierent vliity times se on the istne in hops In igure 8, sens TC with vliity time o two seons or neighors tht re one hop wy, our seons or routers in two-hop istne n six seons in three-hop istne. I is mliious router n moiies the hop ount (sy, y eresing it to 0), then will lulte the vliity time o reeive inormtion to two seons ter whih it expires unless rereshe. I TCs rom re sent less requently thn tht up to 3 hops, this uses links vertise in suh TCs to e only intermittently ville to. 3. EFFECTIVE TOPOLOGY Link-stte protools ssume tht eh router n quire n urte topology mp, releting the eetive network topology. This implies tht the routing protool, through its messge exhnge, ientiies pth rom soure to estintion, n this pth is vli or orwring t tri. I n ttker isturs the orret protool ehvior, the pereive topology mp o router n permnently ier rom the eetive topology. Consiering the exmple in igure 9(), whih illustrtes the topology mp s quire y s. This topology mp inites tht the routing protool hs ientiie tht or s, pth exists to vi, whih it thereore ssumes n e use or trnsmitting t. I, eetively, oes not orwr t tri rom s, then the topology mp in s oes not urtely relet the eetive network topology. Rther, the eetive network topology rom the point o view o s woul e s inite in igure 9(): is not prt o the network rehle rom router s. s s () Pereive topology y s Figure 9. Inorret Dt Tri Forwring () Eetive topology 3.1. Inorret Forwring OLSRv2 routers exhnge inormtion using link-lol trnsmissions (link-lol multist or limite rost) or their ontrol messges, with the routing proess in eh router retrnsmitting reeive messges estine or network-wie iusion. Thus, i the operting system in router is not onigure to enle orwring, this will not et the operting o the routing protool, or the topology mp quire y the routing protool. It will, however, use isrepny etween the eetive topology n the topology mp, s inite in igure 9() n igure 9(). This sitution is not hypothetil. A ommon error seen when eploying OLSRv2 se networks using Linux-se omputers s router is to neglet enling IP orwring Wormholes A wormhole, epite in the exmple in igure 10, my e estlishe etween two ollorting evies, onnete y n out-o-n hnnel; these evies sen tri through the tunnel to their lter-ego, whih replys the tri. Thus, n s pper s-i iret neighors n rehle rom eh other in 1 hop through the tunnel, with the pth through the MANET eing 100 hops long.

8 100 hop long pth s 1 hop long pth vi "wormhole" Figure 10. Wormholing etween two ollorting evies not prtiipting in the routing protool. The onsequenes o suh wormhole in the network epens on the etile ehvior o the wormhole. I the wormhole relys only ontrol tri, ut not t tri, the sme onsiertions s in setion 3.1 pplies. I, however, the wormhole relys ll tri, ontrol n t like, it is onnetivity-wise ientil to usle link n the routing protool will orretly generte topology mp releting the eetive network topology. The eiieny o the topology so otine epens on (i) the wormhole hrteristis, (ii) how the wormhole presents itsel n (iii) how pths re lulte. Assuming tht pths re lulte with unit-ost or ll links, inluing the link presente y the wormhole: i the rel hrteristis o the wormhole re s-i it ws pth o more thn 100 hops (e.g. with respet to ely, nwith,...), then the presene o the wormhole results in egrtion in perormne s ompre to using the non-wormhole pth. Conversely, i the link presente y the wormhole hs etter hrteristis, the wormhole results in improve perormne. I pths re lulte using non-unit-osts or ll links, n i the ost o the link presente y the wormhole orretly represents the tul ost (e.g. i the ost is estlishe through mesurements ross the wormhole), then the wormhole my in the worst se use no egrtion in perormne, in the est se improve perormne y oering etter pth. I the ost o the link presente y the wormhole is misrepresente, then the sme onsiertions s or unit-ost links pply. An itionl onsiertion with regrs to wormholes is, tht suh my present topologilly ttrtive pths or the network however it my e unesirle to hve t tri trnsit suh pth: n ttker oul, y virtue o introuing wormhole, quire the ility to reor n inspet trnsiting t tri Sequene Numer Attks OLSRv2 uses two ierent sequene numers in TCs, to (i) voi proessing n orwring the sme messge more thn one (Messge Sequene Numer), n (ii) to ensure tht ol inormtion, rriving lte ue to e.g. long pths or other elys, is not llowe to overwrite resher inormtion (Avertise Neighor Sequene Numer ANSN) Messge Sequene Numer An ttk my onsist o mliious router spooing the ientity o nother router in the network, n trnsmitting lrge numer o TCs, eh with ierent Messge Sequene Numers. Susequent TCs with the sme sequene numers, originting rom the router whose ientity ws spooe, woul thene e ignore, until eventully inormtion onerning these spooe TCs expires Avertise Neighor Sequene Numer (ANSN) An ttk my onsist o mliious router spooing the ientity o nother router in the network, n trnsmitting single TC, with n ANSN signiintly lrger thn tht whih ws lst use y the legitimte router. Routers will retin this lrger ANSN s the most resh inormtion n isr susequent TCs with lower sequene numers s eing ol.

9 3.4. Messge Timing Attks In OLSRv2, eh ontrol messge my ontin expliit vliity time n intervl time, ientiying the urtion or whih inormtion in tht ontrol messge shoul e onsiere vli until isre, n the time until the next ontrol messge o the sme type shoul e expete [3] Intervl Time Attk A use o the expete intervl etween two suessive HELLOs is or etermining the link qulity in Neighor Disovery proess, s esrie in [6]: i messges re not reeive with the expete intervls (e.g. ertin rtion o messges re missing), then this my e use to exlue link rom eing onsiere s useul, even i (some) i-iretionl ommunition hs een veriie. I mliious spoos the ientity o n existing, n sens HELLOs initing very low intervl time, reeiving this HELLO will expet the ollowing HELLO to rrive within the intervl time inite or otherwise, erese the link qulity or the link -. Thus, my use s estimte o the link qulity or the link - to ll elow the limit, where it is no longer onsiere s useul n, thus, not use Vliity Time Attk A similr ttk with respet to the intervl time ttk uses the vliity time inlue in HELLO n TCs. The vliity time eines how long the inormtion ontine in the messge shoul e onsiere s vli. Ater this time, the reeiving router must onsier the messge ontent to no longer e vli (unless repete in lter messge) [3]. A mliious router,, n spoo the ientity o n sen HELLO using very low vliity time (e.g. 1 ms)., reeiving this, will isr the inormtion upon expirtion o tht intervl, i.e. link - will e torn own y Iniret Jmming Iniret Jmming is n ttk in whih mliious router is, y its tions, using legitimte routers to generte inorinte mounts o ontrol tri, therey inresing oth hnnel ouption n the overhe inurre in eh router or proessing this ontrol tri. This ontrol tri will e originte rom legitimte routers, thus to the wier network, the mliious evie my remin unetete. The generl mehnism wherey mliious evie n use iniret jmming is or it to prtiipte in the protool y generting plusile ontrol tri, n to tune this ontrol tri to in turn trigger reeiving routers to generte itionl tri. For OLSRv2, suh n iniret ttk n e irete t, respetively, the Neighorhoo Disovery mehnism n the Link Stte Avertisement mehnism Iniret Jmming: Neighorhoo Disovery An iniret jmming ttk on the Neighorhoo Disovery proess is illustrte in igure 11. A mliious router,, vertises in HELLO tht it hs s link to, with sttus SYM (t 0 ). This will use, upon reeiving this HELLO, to onsier s 2-hop neighor, n relulte its MPR set seleting s MPR. This MPR seletion is signle y in susequent HELLO (t 1 ). Upon reeipt o this HELLO rom, vertises in HELLO tht the link to is LOST (t 2 ). This will use, upon reeiving this HELLO, to no longer onsier s 2-hop neighor, n relulte its MPR set oringly, i.e. to no longer ontin. This new MPR set in is signle in susequent HELLO (t 3 ). Upon hving reeive this HELLO rom, it my repet the yle, lternting vertising the link - s LOST n SYM. In orer to mximize the impt o the isruption use y this ttk, shoul ensure tht the router, to whih it lterntively vertises link s SYM or LOST, is not otherwise present

10 MPRs: () MPRs: () Inite s SYM Inite s LOST t 0 t 1 t 2 t 3 Figure 11. Iniret Jmming in Neighorhoo Disovery: the mliious spoos link to, lipping etween link sttus SYM n LOST. in the 2-hop neighorhoo or exmple y vertising router not otherwise present in the network. Tht wy, ll neighors reeiving HELLO rom will selet s MPR. A wy o omplishing this is to hve lern ll ientities in the network y overhering ll TCs n seleting (spooing) n ientity not lrey present. will inite its willingness to e nonzero (thus, epting eing selete s MPR) n prtiipte in the Neighorhoo Disovery proeure n my ignore ll other protool opertions, while still remining eetive s n ttker. An esier version o this ttk is to hve simply e present in the network, n prtiipte in the Neighorhoo Disovery proeure. Without spooing link to nother router, lterntes its willingness s vertise in suessive HELLO trnsmissions etween zero (will never e selete s MPR) n 7 (will lwys e selete s MPR). The impt o this version o the ttk is s ove: MPR set relultion n vertisement y neighors o the. The si Neighorhoo Disovery proess o OLSRv2 employs perioi messge emissions, n y this ttk it n e ensure tht or eh messge exhnge etween n, the MPR set in is relulte. As lultion o n optiml MPR set is known to e NP-hr [13], this lone my use internl resoure exhustion in. I the routers in the network hve triggere HELLOs enle, n tht suh re triggere y MPR set uptes (s suggeste in setion 9 in [5]) this ttk my lso use n inrese HELLO requeny. A minimum messge intervl (typilly muh smller thn the regulr perioi messge intervl) is impose, to rte-limit worst-se messge emissions. This ttk n use the HELLO intervl to, permnently, eome equl to the minimum messge intervl. [5] proposes tht eult tht the minimum HELLO intervl e 1 4 HELLO intervl. Iniret Jmming o the Neighorhoo Disovery proess y mliious router n thus hve two eets: to use inrese requeny o HELLO genertion n trnsmission y neighors o the mliious router, i.e. up to two hops wy rom the mliious router, n to use itionl MPR set lultion in the routers whih re neighors o mliious router Iniret Jmming: Link Stte Avertisement The most eiient Iniret Jmming ttk in OLSRv2 is to trget ontrol tri, estine or network-wie iusion. This is illustrte in igure 12. The mliious selets the s MPR (t 0 ) in HELLO. This uses to pper s MPR seletor or n, onsequently, sets to e vertise in its Neighor Set n inrements the ssoite Avertise Neighor Sequene Numer (ANSN). must, then, vertise the link etween itsel n in susequent outgoing TCs (t 1 ), lso inluing the ANSN in suh TCs. Upon hving reeive this TC, it elres the link etween itsel n s no longer vli (t 2 ) in HELLO (initing the link to s LOST). Sine only symmetri links re

11 ANS={} ANSN++ TC: (-) ANSN ANS={} ANSN++ TC: () ANSN Selet s MPR Inite s LOST t 0 t 1 t 2 t 3 Figure 12. LOST. Iniret Jmming in Link Stte Avertisement: the mliious lips etween link sttus MPR n vertise y OLSRv2 routers, will upon reeipt hereo remove rom the set o vertise neighors n inrement the ANSN. will then in susequent TCs vertise the remining set o vertise neighors (i.e. with remove) n the orresponing ANSN (t 3 ). Upon hving reeive this inormtion in nother TC rom, it my repet this yle, lternting vertising the link - s LOST n s MPR. Routers reeiving TC will prse n proess this messge, speiilly upting their topology mp s onsequene o suessul reeipt. I the ANSN etween two suessive TCs rom the sme router hs inremente, then the topology hs hnge n routing tles re to e relulte. This is potentilly omputtionlly ostly opertion [14]. A mliious router my hose to onut this ttk ginst ll its neighors, thus ttining mximum isruptive impt on the network with reltively little overhe o its own: other thn prtiipting in the Neighorhoo Disovery proeure, the mliious router will monitor TCs generte y its neighors n lternte the vertise sttus or eh suh neighor, etween MPR n LOST. The mliious router will inite its willingness to e zero (thus, voi eing selete s MPR) n my ignore ll other protool opertions, while still remining eetive s n ttker. The si opertion o OLSRv2 employs perioi messge emissions, n y this ttk it n e ensure tht eh suh perioi messge will entil routing tle relultion in ll routers in the network. I the routers in the network hve triggere TCs enle, this ttk my lso use n inrese TC requeny. Triggere TCs re intene to llow (stle) network to hve reltively low TC emission requenies, yet still llow link rekge or link emergene to e vertise through the network rpily. A minimum messge intervl (typilly muh smller thn the regulr perioi messge intervl) is impose, to rte-limit worst-se messge emissions. This ttk n use the TC intervl to, permnently, eome equl to the minimum messge intervl. [5] proposes s eult tht the minimum TC intervl e 4 1 TC intervl. Iniret Jmming y mliious router n thus hve two eets: it my use inrese requeny o TC genertion n trnsmission, n it will use itionl routing tle relultion in ll routers in the network. 4. INCONSISTENT TOPOLOGY Inonsistent topology mps n our y mliious router employing either o ientity spooing or link spooing or onuting n ttk ginst n OLSRv2 network Ientity spooing Ientity spooing n e employe y mliious router vi the Neighorhoo Disovery proess n vi the Link Stte Avertisement proess; either o whih using inonsistent topology mps in routers in the network.

12 Inonsistent Topology Mps ue to Neighorhoo Disovery Consiering the network in igure 13, two routers in r ens o the network oth present themselves uner the sme ientity s x. The routers jent to these two routers ( n w in igure 13) oth pereive x s iret neighor, whih will e relete in the neighor tles n routing tles o these two routers. Thus, the irst onsequene is, tht tri estine or x rom n w, respetively, will e elivere to ierent routers. As the Neighorhoo Disovery proeure lso provies topologil inormtion up to two hops wy, this is lso true or tri estine or x rom n v, respetively. x v w spoos x Figure 13. Ientity Spooing: router (gry irle) ssumes the ientity o router x, lote r wy in the network. Assuming unit-ost links, the istne to x rom n w, s proue y the Neighorhoo Disovery proeure, is 1 hop. The istne to x rom n v, s proue y the Neighorhoo Disovery proeure, is 2 hops. As these istnes re shorter thn (or equl to) the pth lengths otine vi the Link Stte Avertisement proeure, they will thereore e preerre y,, v n w, over those quire vi the Link Stte Avertisement proeure or when lulting routing tles. Thus, i the gry router in igure 13 is the one spooing the ientity o the white router x, then ny tri rom or trnsiting through w n estine or x will e elivere to the gry router inste o to the white x. This hs s impt tht router spooing the ientity o nother router, n y simply prtiipting in the Neighorhoo Disovery proeure, will e le to lter the topology mps in routers up to 2 hops wy, n therey (i) ttrt the tri rom or trnsiting through routers up to two hops wy, whih is otherwise estine or the router whose ientity is eing spooe; n (ii) prevent tri rom or trnsiting through routers up to two hops wy, whih is otherwise estine or the router whose ientity is eing spooe, rom rehing the intene estintion. Strtegi plement o mliious router spooing the ientity o nother router (or other routers) in the network, n simply prtiipting only in the Neighorhoo Disovery proess, n therey eiiently isrupt network onnetivity. First, overhering TCs will llow the router to lern suiient inormtion esriing the network topology to evelop n ttk strtegy whih hs mximum isruptive impt. Seon, y prtiipting only in the Neighorhoo Disovery proeure (i.e. y vertising its willingness s zero, n y not seleting MPRs), n y reully seleting the ientities to spoo, the mliious router n remin iiult to etet. e g spoos:,,, g Figure 14. Ientity Spooing: mximizing isruptive impt while minimizing risk o etetion. Consier the exmple in igure 14: overhers n lerns the network topology. In orer to minimize the risk o etetion, it elets to not selet ny MPRs (therey no Link Stte Avertisements re sent, vertising its presene in the network) n vertises its willingness s zero (therey it is not selete s MPR n thus not require to sen Link Stte Avertisements). lso elets to spoo the ientity o,, n g only. As oes not prtiipte in the Link Stte Avertisement proess, its presene is known only to, n e, i.e. the routers whose ientity it spoos will not reeive ontrol messges llowing them to etet tht these ientities re lso vertise elsewhere in the network. Tri trnsiting, rom either sie, to estintions,, n g will, rther thn eing orwre to the intene estintion, e elivere to.

13 Tri trnsiting n with s estintion will e elivere to the intene router. Tri trnsiting n with s estintion my e elivere to the intene router vi or to vi s the pths will e o equl length. In igure 14, is the only router whih will reeive ontrol tri initing two topologi lotions o the ientities,. However, espeilly in wireless environment, this is not in n y itsel unusul: vli link might inee exist etween n s well s etween n, e.g. through nother wireless hnnel. Thus, the topology s pereive y n e oes not pper improle. I the network grows to the let o or to the right or g, ll hs to o to ontinue isrupting the network is to lern the ientities o the routers eyon n g n lso spoo the ientities o these. In generl, or mximum isruptive impt n minimum visiility, the mliious router woul selet to spoo the ientities o ll routers whih re topologilly 3 hops or more wy rom itsel. Ientity spooing y mliious router, stritly prtiipting only in the Neighorhoo Disovery proess, thus, retes sitution wherein two or more routers hve sustntilly inonsistent topology mps: tri or n ientiie estintion is, epening on where in the network it ppers, elivere to ierent routers Inonsistent Topology Mps ue to Link Stte Avertisements An inonsistent topology mp my lso our when the mliious router tkes prt in the Link Stte Avertisement (LSA) proeure, y seleting neighor s MPR, whih in turn vertises the spooe ientities o the mliious router. This ttk will lter the topology mps ll routers o the network. spoos e Figure 15. Ientity Spooing: mliious router spoos the ientity o, leing to wrongly pereive topology. In igure 15, spoos the ress o. I selets s MPR, ll routers in the network will e inorme out the link - y the TCs originting rom. Assuming tht (the rel) selets s MPR, the link - will lso e vertise in the network, resulting in pereive topology s epite in igure 16. e Figure 16. Ientity Spooing: the gry mliious router spoos the ientity o router. When lulting pths, n will lulte pths to vi, s illustrte in igure 17(); or these routers, the shortest pth to is vi. e n will lulte pths to vi, s illustrte in igure 17(); or these routers, the shortest pth to is vi the mliious router, n these re thus isonnete rom the rel. will hve hoie: the pth lulte to vi is o the sme length s the pth vi the mliious router, s illustrte in igure 17(). In generl, the ollowing oservtions n e me: The network will e split in two, with those routers loser to thn to rehing, wheres those routers loser to thn to will e unle to reh. Routers eyon, i.e. routers eyon one hop wy rom will e unle to etet this ientity spooing. The ientity spooing ttk vi the Link Stte Avertisement proeure hs higher impt thn the ttk esrie in setion 4.1.1, sine it lters the topology mps o ll routers in the network, n not only in the 2-hop neighorhoo. However, the ttk is esier to etet

14 spoos g () Routers n. () Routers e n. spoos e () Router. Figure 17. Routing pths towrs, s lulte y the ierent routers in the network in presene o mliious router, spooing the ress o. y other routers in the network. Sine the mliious router is vertise in the whole network, routers whose ientities re spooe y the mliious router n etet the ttk. For exmple, when reeives TC rom vertising the link -, it n eue tht some entity is injeting inorret Link Stte inormtion s it oes not hve s one o its iret neighors. As the mliious router oes not itsel sen the TCs, ut rther, y virtue o MPR seletion, ensures tht the resses it spoos re vertise in TCs rom its MPR seletor, the ttk my e iiult to ounter: simply ignoring TCs tht originte rom my lso suppress the link stte inormtion or other, legitimte, MPR seletors o. Ientity spooing y mliious router, prtiipting in the Link Stte Avertisement proess y seleting MPRs only, thus, retes sitution wherein two or more routers hve sustntilly inonsistent topology mps: tri or n ientiie estintion is, epening on where in the network it ppers, elivere to ierent routers Link Spooing Link Spooing is sitution in whih router vertises non-existing links to nother router (possily not present in the network). Essentilly, TCs n HELLOs oth vertise links to iret neighor routers, with the ierene eing the sope o the vertisement. Thus, link spooing onsists o mliious router, reporting tht it hs s s neighors routers whih re, either, not present in the network, or whih re eetively not neighors o the mliious router. It n e note tht sitution similr to Link Spooing my our temporrily in n OLSR or OLSRv2 network without mliious routers: i ws, ut is no more, neighor o, then my still e vertising link to or the urtion o the time it tkes or the the Neighorhoo Disovery proess to etermine this hnge neighorhoo. In the ontext o this pper, Link Spooing reers to persistent sitution where mliious router intentionlly vertises links to other routers, or whih it is not iret neighor Inonsistent Topology Mps ue to Neighorhoo Disovery Returning to igure 4(), MPR seletion serves to ientiy whih routers re to vertise whih links in the network s prt o the Link Stte Avertisement proess.olsrv2 stipultes tht router must, s minimum, vertise links etween itsel n its MPR seletors, i.e. links etween itsel n the routers whih hve selete it s MPR. A router is not require to vertise other links. Thus, in the exmple network in igure 4() with seleting the mliious router s its sole MPR, only is expete to vertise links to. s selets s its MPR, thus is expete to vertise the link -S. s, then, expets to hve selete suitle MPRs or the MPR looing proess to suee in network-wie iusion o the vertisement o the link -s. The topology mps quire y the vrious other routers in this exmple re: Routers n will, ue to the Neighorhoo Disovery proess proviing topologil inormtion up to 2 hops wy, quire n urte Topology Mp. For this is extly

15 orresponing to the network in igure 4(). For this my or my not ontin the otte routers n w, epening on whether genertes Link Stte Avertisements (see setion 4.2.2). Router will pereive topology mp s illustrte in igure 18(): the link stte vertisements rom re not orwre y, hene the existene o s n the link -s is not known eyon ; the sme is true or link stte vertisement rom, shoul it prtiipte in the link stte vertisement proess. The link -, n the existene o is known to only through the Neighorhoo Disovery proess. Routers n eyon will reeive Topology Mp s illustrte in igure 18(). Router s will quire n urte Topology Mp orresponing to the network in igure 4(). This my or my not ontin the otte routers n w, epening on i router genertes Link Stte Avertisements (see setion 4.2.2). () Inonsistent Topology Mp in. () Inonsistent Topology Mp in n eyon. Figure 18. Pereive Topology Mps with perorming Link Spooing in the Neighorhoo Disovery Proess: In orer to mximize the impt o the isruption o Link Spooing in the Neighorhoo Disovery proess, the mliious router my simultneously spoo links to multiple routers: y overhering ontrol tri or while, my ttempt to lern the ientities o 2-hop neighors o n spoo these n, in ition, ssume t lest one itionl ientity (possily not otherwise present in the network). A wy o hieving this is to simply hve the mliious overher ll TCs, n spoo links to ll ientities o ll routers in the network, plus one ientity not otherwise present in the network. As the set o links spooe y is thus superset o the 2-hop links s seen rom, will selet s its sole MPR. e g h i g h i Figure 19. Link Spooing: Mliious router spoos links to ll routers in the network exept router e. By only prtiipting in the Neighorhoo Disovery n not the LSA proess, it is more iiult to etet the spooing, while in the sme time isturing the topology o the whole network. Symmetri to igure 14, igure 19 illustrtes network with is positione in the mile. I vertises links to,,,,, g, h n i in the Neighorhoo Disovery proess, these ientities s spooe y re visile only to e s 2-hop neighors. e my etet tht no link to is vertise y its own 1-hop neighor routers n. Thus, to voi suh etetion y e, shoul voi spooing links to routers vertise s 1-hop neighors y e, i.e. vertise in its HELLOs only spooe links to,,, g, h n i, s illustrte in igure 20. The impt o this this ttk is tht: will pper s the most ttrtive nite MPR or e, y virtue o spooing links to ll other 2-hop neighors o e n then some. Thus, sent or initing willingness o 7, will e selete s the sole MPR o e. No routers, other thn, will e requeste to sen Link Stte Avertisements, vertising links to the. No routers, other thn, will e requeste to orwr looe tri originting in or trnsiting through.

16 e g h i g h i Figure 20. Link Spooing: remins more iiult to e etete when it oes not vertise spooe links to routers t most 2 hops wy Inonsistent Topology Mps ue to Link Stte Avertisements Figure 21 illustrtes network, in whih the mliious router spoos links to the existing router y prtiipting in the Link Stte Avertisement proess n inluing this non-existing link in its vertisements. e g Figure 21. Link Spooing: The mliious router vertises spooe link to in its TCs, thus ll routers will reor oth o the links - n -. As TCs re looe through the network, ll routers will reeive n reor inormtion esriing link - in this link stte inormtion. I hs selete router s MPR, will likewise loo this link stte inormtion through the network, thus ll routers will reeive n reor inormtion esriing link -. When lulting routing pths,, n will lulte pths to vi, s illustrte in igure 22(); or these routers, the shortest pth to is vi. n g will lulte pths to vi, s illustrte in igure 22(); or these routers, the shortest pth to is vi, n these re thus isonnete rom the rel router. e will hve hoie: the pth lulte to vi is o the sme length s the pth vi, s illustrte in igure 22(). g () Routers, n. () Routers n g. e g () Router e. Figure 22. Routing pths towrs router, s lulte y the ierent routers in the network in presene o mliious router, spooing link to router. In generl, the ollowing oservtions n e me: The network will e seprte in two, with those routers loser to thn to rehing, wheres those routers loser to thn to unle to reh. Routers eyon, i.e. routers eyon one hop wy rom will e unle to etet this link spooing. Returning to igure 19, i vertises spooe links to,,,,, g, h n i in Link Stte Avertisements, the risk o etetion y e is ientil to i these were vertise in the Neighorhoo Disovery proess: e my etet tht is vertising links to n, while is not reore s 2-hop neighor vi neither nor. Suppressing links to n rom eing vertise y the woul prevent e rom eteting tht is mliious. However, upon reeiving Link Stte Avertisement, router is le to etet i it itsel is eing spooe the vertising router is not neighor o the router eing

17 spooe. Furthermore, or the resons elorte ove, routers up to one hop wy rom the spooe estintion my etet the spooing. In the se o igure 20 woul e le to etet spooing o links to (s woul e le to etet spooe links to et.) possily leing to signiint rtion o routers eing le to etet tht is onuting isruptive ttk n, thereore, engging pproprite ountermesures. e woul, in this se, e the only router unle to etet the spooing. While this might suie to isrupt the network, it is no ierent rom the ientity spooing ttk illustrte in igure 14, whih rries less risk o etetion o the mliious router. The impt o this ttk is similr to tht presente in setion 4.1.2, however, is esier to etet s the mliious router is generting ontrol tri rehing the entire network Creting Loops Consier the exmple in igure 23(). The mliious router,, spoos the ientity o g, n prtiiptes (with this spooe ientity) in oth the Neighorhoo Disovery proess n the Link Stte Avertisement proess. In orer to over ll its 2-hop neighors, must selet oth n s MPRs. Hene, the link - is vertise y, n the link g- is vertise y the mliious router. Spoos g Spoos g Dt to g h g h e e () Rel network topology, with mliious router spooing the ientity o g. () Topology Mp in. Spoos g Dt to g h e () Topology Mp in g. Figure 23. Pereive Topology Mps with mliious router perorming Ientity Spooing in the Link Stte Avertisement proess The topology pereive y is s inite in igure 23(): pths to the estintion exist vi g (2 hops) or vi e (3 hops). The topology pereive y g is s inite in igure 23(): s g oes not proess TCs originting rom itsel, the only pth reognize y g towrs is vi. Thereore, i t pket estine or rrives t, it will e orwre through g. g will orwr the t pket through, therey reting loop in the network. Consier the exmple in igure 24(). The mliious router,, spoos the ientity o g, n selets s MPR. Hene, the link -g is vertise y is trike into vertising non-existing link. The topology pereive y is s inite in igure 24(): pths to the estintion exists is vi g (2 hops) or vi (3 hops). The topology pereive y g is s inite in igure 24(): s g oes not proess TCs originting rom itsel, the only pth reognize y g towrs is vi. Thereore, i t pket estine or rrives t, it will e orwre through g. g will orwr the t pket through, therey reting loop in the network.

18 Dt to Spoos g g h g h () Rel network topology, with mliious router spooing the ientity o g. () Topology Mp in router. Dt to g h () Topology Mp in router g. Figure 24. Pereive Topology Mps with mliious router perorming Ientity Spooing in the Neighorhoo Disovery proess 5. WHY THIS PAPER DOES NOT CONSIDER REPLAY ATTACKS A ommonly onsiere ttk type is or mliious router to reor ontrol tri rom legitimte routers, n reply this possily somewhere else in the network, n possily t some lter point in time. While suh inee is possile, it shoul not e onsiere s lss o ttks on OLSRv2 in n y itsel: in-ine, the mliious router replying messges is perorming omintion o ientityspooing, spooing the ientity o the router rom whih it reore the messges, n link-spooing, spooing links to the (originl) neighors o tht router. Thus, the impt o suh reply ttk is no ierent rom the impt esrie or ientity-spooing n link-spooing. 6. INHERENT OLSRV2 RESILIENCE While OLSRv2 oes not speiilly inlue seurity etures (suh s enryption), the protool n its lgorithms present some inherent resiliene ginst prt o the ttks esrie in this pper. In prtiulr, it provies the ollowing resiliene: Sequene numers: OLSRv2 employs messge sequene numers, speii per router ientity n messge type. Routers keep n inormtion reshness numer (ANSN), inremente eh time the ontent o Link Stte Avertisement rom router hnges. This llows rejeting ol inormtion n uplite messges, n provies some protetion ginst messge reply. This, however, lso presents n ttk vetor (setion 3.3). Ignoring uni-iretionl links: The Neighorhoo Disovery proess etets n mits only i-iretionl links or use in MPR seletion n Link Stte Avertisement. Jmming ttks (setion 2.2) my et only reeption o ontrol tri, however OLSRv2 will orretly reognize, n ignore, suh link s not i-iretionl. Messge intervl ouns: The requeny o ontrol messges, with minimum intervls impose or HELLO n TCs. This my limit the impt rom n iniret jmming ttk (setion 3.5). Aitionl resons or rejeting ontrol messges: The OLSRv2 speiition inlues list o resons, or whih n inoming ontrol messge shoul e rejete s mlorme n llows tht protool extension my reognize itionl resons or OLSRv2 to onsier messge mlorme. This llows together with the lexile messge ormt [2] ition o seurity mehnisms, suh s igitl signtures, while remining omplint with the OLSRv2 stnr speiition. 7. CONCLUSION This pper hs presente etile nlysis o seurity threts to the Optimize Link Stte Routing Protool version 2 (OLSRv2), y tking n strt look t the lgorithms n messge

19 exhnges tht onstitute the protool, n or eh protool element ientiying the possile vulnerilities n how these n e exploite. In prtiulr, s link-stte protool, OLSRv2 ssumes tht (i) eh router n quire n mintin topology mp, urtely releting the eetive network topology; n (ii) tht the network onverges, i.e. tht ll routers in the network will hve suiiently ientil (onsistent) topology mps. An OLSRv2 network n e eetively isrupte y reking either o these ssumptions, speiilly () routers my e prevente rom quiring topology mp o the network; () routers my quire topology mp, whih oes not relet the eetive network topology; n () two or more routers my quire sustntilly inonsistent topology mps. The isruptive ttks to OLSRv2, presente in this pper, re lssiie in either o these tegories. For eh, it is emonstrte, whether OLSRv2 hs n inherent protetion ginst the ttk. REFERENCES [1] T. Clusen, C. Derlove, B. Amson, RFC5148: Jitter Consiertions in Moile A Ho Networks (MANETs), Inormtionl, [2] T. Clusen, C. Derlove, J. Den, C. Ajih, RFC5444: Generlize Moile A Ho Network (MANET) Pket/Messge Formt, St. Trk, [3] T. Clusen, C. Derlove, RFC5497: Representing Multi-Vlue Time in Moile A Ho Networks (MANETs), St. Trk, [4] T. Clusen, C. Derlove, J. Den, I-D: MANET Neighorhoo Disovery Protool (NHDP), Work In Progress, [5] T. Clusen, C. Derlove, P. Jquet, I-D: The Optimize Link Stte Routing Protool version 2 (OLSRv2), Work In Progress, [6] T. Clusen, P. Jquet, RFC3626: Optimize Link Stte Routing Protool (OLSR), Experimentl, [7] [8] C. Hutzler, D. Croker, P. Resnik, E. Allmn, T. Finh Emil Sumission Opertions: Aess n Aountility Requirements, Best Current Prtie, [9] A. Qyyum, L. Viennot, A. Louiti, Multipoint relying: An eiient tehnique or looing in moile wireless networks, 35th Annul Hwii Interntionl Conerene on System Sienes (HICSS 2001) [10] Y. Li, C. Wng, W, Zho,. You, The Jmming prolem in IEEE se moile ho networks with hien terminls: Perormne nlysis n enhnement, Interntionl Journl o Communition Systems, Volume 22 Issue 8, Pges , April 2009 [11] IEEE : Wireless LAN Meium Aess Control (MAC) n Physil Lyer (PHY) Spe., June 2007 [12] C. Ajih, E. Belli, T. Clusen, P. Jquet, G. Roolkis, Fish eye OLSR sling properties, IEEE Journl o Communition n Networks (JCN), Speil Issue on Moile A Ho Wireless Networks, 2004 [13] L. Viennot, Complexity results on eletion o multipoint relys in wireless networks, INRIA, Teh. Rep. RR-3584, 2007 [14] U. Hererg, Perormne Evlution o using Dynmi Shortest Pth Algorithm in OLSRv2, (To Apper) Proeeings o the 8th Eighth Annul Conerene on Communition Networks n Servies Reserh, My 2010, Montrel, Cn [15] T. Clusen, G. Hnsen, L. Christensen, G. Behrmnn, The Optimize Link Stte Routing Protool, Evlution through Experiments n Simultion, Proeeings o the IEEE onerene on Wireless Personl Multimei Communitions (WPMC), Otoer 2001, Alorg, Denmrk [16] Ntionl Institute o Stnrs & Tehnology, Reommention or Key Mngement Prt 1: Generl, NIST, Speil Pulition , Mrh 2007 [17] D. Estlke, P. Jones, US Seure Hsh Algorithm 1 (SHA1), Inormtionl, [18] B. Kliski, J. Ston, PKCS 1: RSA Cryptogrphy Speiitions Version 2.0, Inormtionl, [19] Ntionl Institute o Stnrs & Tehnology, Digitl Signture Stnr, NIST, FIPS PUB 186-3, June 2009 [20] D. Johnson, A. Menezes, S. Vnstone, The Ellipti Curve Digitl Signture Algorithm (ECDSA), Interntionl Journl o Inormtion Seurity, Volume 1, Numer 1 / August, pges 36-63, 2001

20 [21] H. Krwzyk, M. Bellre, R. Cnetti, HMAC: Keye-Hshing or Messge Authentition, Inormtionl, txt [22] U. Hererg, JOLSRv2 An OLSRv2 implementtion in Jv, Proeeings o the 4th OLSR Interop workshop, Otoer 2008 [23] U. Hererg, Integrting Jv Support or Routing Protools in Ns2, INRIA reserh report 7075, Ot [24] G. J. Pottie, W. J. Kiser, Wireless integrte network sensors, Communitions o the ACM, volume 43, numer 5, pge 51-58, Ulrih Hererg grute in omputer siene rom TU Munih in 2007, n then joine Eole Polytehnique (Frne), where he is urrently PhD stuent. His reserh interests over routing n seurity issues in MANETs, uto-onigurtion, n ely-tolernt networks. Thoms Clusen is grute o Alorg University, Denmrk (M.S., PhD - ivilingeniør, n. polyt), Thoms spent numer o yers t INRIA where he, mong other things, spent his time eveloping n stnrising OLSR. In 2004 he joine ulty t Eole Polytehnique, Frne s premiere tehnil university. Thoms hs prtiulr inity or pplile reserh, n enjoys working with inustril prtners n stnristion oies. He is, thus o-hir o the MANET AUTOCONF working group within the IETF, s well s the uthor n eitor o severl stnr trk n other ouments within the IETF.