Ukuphela kwesikhathi sokuxhumana kwe-VPN: i-DNS, ukuthuthwa, ukuxoxisana noma ukungena
Ukuphela kwesikhathi kusho kuphela ukuthi isikhathi esithile sedlulile. Qhathanisa izigaba ezine, ukuxazululwa kwegama, ukuthuthwa, ukuxoxisana nokungena, ukubona esiphele isikhathi sokugcina.
“Ukuxhumana kuphelelwe isikhathi” iyiphutha elingacacile kakhulu iklayenti le-VPN elingaliphrinta. Kusho ukuthi umsebenzi owodwa weqe isikhathi sawo, futhi isigaba ngasinye kusukela ekuxazululweni kwegama kuze kufike impendulo yokungena sinesikhathi. Amaklayenti akhombisa umyalezo wokugcina kuphela enza izigaba zibonakale zifana, ngakho abantu banyusa isikhathi, bashintsha imbobo futhi bafaka kabusha iphrofayela, ngalolo hlelo, ngaphandle kokufunda lutho. Ukuqhathanisa izigaba kuyashesha: ngasinye sihluleka endaweni ehlukile, futhi ukwehluleka ngakunye kushiya uhlobo oluhlukile lobufakazi.
Izigaba ezine, ukwehluleka okune okuhlukile
Ukulandelana kuqinile ngisho nalapho iklayenti likufihla: igama kufanele lixazululwe, ukuthuthwa kufanele kusungulwe kuya ekhelini eliwumphumela, iphrothokholi kufanele ixoxisane ngamapharamitha nezikhiye zayo, futhi i-akhawunti kufanele iqinisekiswe. Umhlahlandlela we-OpenVPN wokuxazulula izinkinga zokuxhumana ulandela ukulandelana okufanayo kuklayenti layo, kanti ezinye zikulandela eduze. Ukuphela kwesikhathi esigabeni sesibili nesesine akukho okufanayo ngaphandle kwegama elikusikrini.
| Stage | Looks like | What it does not prove |
|---|---|---|
| Name resolution | fails in under a second, before any contact | nothing about the server being up |
| Transport | waits the full timeout, then gives up | nothing about the VPN service behind the port |
| Negotiation | connects, then stalls at handshake | nothing about credentials |
| Login | a reply arrives and is rejected or hangs on a prompt | nothing about reachability |
Funda ilogi ufuna umugqa wokugcina okhombisa inqubekelaphambili, hhayi umugqa wokugcina ngaphambi kwephutha. Iningi lamaklayenti liphrinta into efana nekheli elixazululiwe, isokhethi esunguliwe, ukuxhawana okuqaliwe noma isicelo sokuqinisekisa, futhi isigaba esilandelayo salowo mugqa yiso esiphelelwe isikhathi.
Ukuxazululwa kwegama kwehluleka ngaphambi kokuxhumana nanoma yini
Uma iphuzu lokugcina lingaxazululwa neze, iklayenti alinalutho elingaxhumana nalo futhi awukho umsebenzi wokuthutha owenzekile. Lokho kwehluleka kuvame ukuba ngokushesha hhayi isikhathi esigcwele, futhi leyo iyona ndlela eshibhile yokwehlukanisa kwezinye. Hlola igama ngesixazululi sohlelo kanye nesixazululi sesibili, bese uqhathanisa izimpendulo ezimbili ngaphambi kokuphetha ngokuthi iseva iphansi.
Ikheli elidala elikopishelwe embhalweni weforum iyimbangela ejwayelekile yokuphela kwesikhathi okubonakala njengenkinga yeseva, ngoba ikheli manje lingelinye into noma akukho lutho. Sebenzisa iphrofayela yamanje yomhlinzeki esikhundleni sokushintsha ikheli elalisebenza ngaphambili. Ukungabikho kwempendulo ye-ping akubona ubufakazi kunoma yiluphi uhlangothi: amaphuzu amaningi okugcina alahla i-ICMP kanti asasebenza kahle kakhulu.
Ukusethwa kokuthutha kulinde iphakethe elingeke lize
Lapho i-DNS ilungile futhi iklayenti lisashisa sonke isikhathi, ungqimba lokuthutha luyasolwa. Ku-TCP ungahlola imbobo ngqo; Test-NetConnection ku-Windows noma nc -vz ku-Linux kukutshela ukuthi kukhona okwamukela ukuxhumana yini, futhi lokho kuwusizo ukwedlula i-ping. Ku-UDP awukwazi ukuhlola ngendlela efanayo, ngoba kulolo ngqimba akukho ukuxhawana okufanele kuqedwe, futhi lokhu kungalingani kubangela iziphetho eziningi ezingalungile.
Lokho ukuhlolwa kwe-TCP okukufakazayo kunomkhawulo: isevisi eyamukela imbobo 443 ayiyona ngempela isilaleli se-VPN, futhi iphuzu lokugcina le-UDP kuphela alinayo imbobo ye-TCP yokwamukela noma yini. Ukubhala kabusha iphrofayela isuka ku-UDP iye ku-TCP akudali isilaleli ngaphesheya; kushintsha kuphela lokho iklayenti lakho elikulindile. Uma inethiwekhi ihlunga iphrothokholi, ushintsho lukhiqiza esinye isikhathi sokuphela esigabeni esifanayo.
Amaphothali acindezelayo afanele ukuhlolwa kwawo kulesi sigaba. Kuze kube iphothali igunyaza idivayisi, ukuthuthwa okuphumayo kuya ephothalini futhi umzamo wethaneli uvele ulengiswe nje. Qeda iphothali kusiphequluli kuqala, bese uzama futhi, futhi ungayishintshi iphrofayela ngenkathi iphothali isalindile.
Ukuxoxisana nokungena kusho ukuthi iseva iphendulile
Uma ithaneli lifika esevini, iklayenti liqala ukuxhawana futhi uphawu lwephutha lushintsha. Ukuma lapha kumayelana nokuhambisana hhayi ukufinyeleleka: izinguqulo zephrothokholi ezingahambisani, ukusethwa kwe-cipher noma kwesiteshi sedatha iseva engakwamukeli, noma iphrofayela elilindele isici iseva engasinikezi. OpenVPN ishintsha izindinganiso zayo zokuxoxisana phakathi kwezinguqulo ezinkulu kaningi ngokwanele ukuthi iphrofayela ebhalelwe isizukulwane esisodwa ingafika esevini futhi ingakwazi ukuphakama.
Ukuqinisekisa yisigaba sokugcina futhi yiso esilula ukusifunda ngokungalungile. Ukwenqatshwa okucacile kuyimpendulo, okusho ukuthi indlela iyasebenza futhi inkinga isekuqhutsheni umuntu, isitifiketi noma isimo se-akhawunti. Ukugeleza kokungena okukodwa okusekelwe kusiphequluli kuyisimo sesithathu: iklayenti lilinde isenzo ongasenzanga, noma isiphequluli esingakwazi ukusivula, futhi akukho okuzofika kuze kube uqeda leso sinyathelo.
Qhathanisa ubufakazi ngaphambi kokushintsha umzamo wokuzama futhi
Gcina idivayisi nephrofayela kungekho okushintshayo futhi ushintshe into eyodwa ngesikhathi, uqala ngenethiwekhi. Uma iphrofayela efanayo ixhuma ku-hotspot yefoni futhi iphelelwe isikhathi ku-Wi-Fi yehhotela, okushintshayo indlela hhayi iseva. Uma yehluleka yonke indawo, okushintshayo iphrofayela noma iphuzu lokugcina. Uma yehluleka kuphela ngesikhathi esithile sosuku, thatha isigxivizo sesikhathi bese usiqhathanisa nezehlakalo ohlangothini lweseva ngaphambi kokucabanga noma yini ngomthwalo.
Kumsebenzi owuqondayo, ukuqhathanisa okunqumayo ukuthi umzamo uyafika yini. Ukuxhumana okufika kusilaleli bese kuma kungokwesigaba sokuxoxisana; lokho okungaveli neze emehlweni esilaleli kuyinkinga yokuthutha noma yokuxazulula, futhi akukho kulungiswa kokuzama futhi okuzakususa. Amalogi eseva ahlukanisa nokungena okwenqatshiwe nokuwa buthule, futhi lowo umehluko phakathi kokulungisa ubuwena nokulungisa udonga lomlilo.
Rekhoda inguqulo yeklayenti, igama lephrofayela, isikhathi somzamo kanye nesigaba sesikhathi saso kanye nephutha lokuqala eliwusizo esikhundleni somugqa wokugcina wokunqanyulwa. Susa izikhiye kanye nempahla ephethe imininingwane yokungena ngaphambi kokwabelana ngesiqephu. Bese wenza ukulungiswa okukodwa okunengqondo bese uzama futhi, ngoba isikhathi eside sisiza kuphela umsebenzi ohamba kancane obhalwe phansi futhi asenzi lutho ngekheli elingalungile noma imbobo evinjiwe.