VPN da TURN relay: wanne ne yake ɗaukar kiran WebRTC da gaske?
Tunnel yana canza hanyar da ICE ke gani; ba ya taɓa ba da relay kuma ba ya samar da sigina. Kwatanta abin da fitowar VPN da uwar garken TURN kowanne ke bayarwa.
Shafin yana lodawa ta VPN, amma kiran ba ya taɓa haɗuwa: kuskure biyu daban-daban a sandar adireshi ɗaya. Tunnel ɗin ya canza hanyar da burauza ke amfani da ita; bai zama sabis ɗin sigina ba, ba uwar garken STUN ba, ba relay ba, kuma ba ya yanke shawarar wace takwarar ɗan takara ICE zai zaɓa. Rarraba aikin da kowane ɓangare yake yi shi ne ke mai da “an toshe WebRTC” marar tabbas ya zama tabbataccen kuskure.
Ayyuka huɗu, wanda tunnel ɗin ya taɓa ɗaya kawai
Aikace-aikacen yana musayar bayanan zama ta wani tsarin sigina, kuma wannan shi ne aiki na farko. ICE yana tattara adiresoshin ƴan takara kuma yana gwada ma'aurata har ɗaya ya yi aiki, wanda shi ne na biyu. STUN yana ba abokin tafiyar damar sanin yadda zirga-zirgarsa take kamar daga waje, kuma TURN yana ba da relay ga lokuta da babu hanyar kai tsaye. Waɗannan matsayi huɗu daban-daban ne, kuma VPN yana shafar adiresoshi da tacewar da suke fuskanta maimakon samar da ɗayansu.
Shi ya sa shiga mai nasara ba ya faɗin komai game da hanyar kafofin watsa labarai. Sigina yawanci yana tafiya a kan HTTPS ɗin da shafin ke amfani da shi tun farko, a tashar 443, yayin da kafofin watsa labarai na iya tafiya ta UDP zuwa wata manufa dabam.
Adireshi na sirri yana ƙara rikicewa. Adireshin tunnel yana da amfani ga abokin tafiya ne kawai idan wannan abokin yana da hanyar dawowa da aka yi niyya zuwa gare shi; kasancewa na sirri ba hujja ba ce ta isa ga juna, kuma burauza ba sa ɗaukarsa haka sa'ad da suke watsar da ƴan takara da ba za a iya gwadawa ba. Ɗan takarar da yake maka kama da na gida na iya kasancewa ba za a iya gwadawa ba daga ɗaya gefen. Ya kamata a kawar da wannan gibin kafin ka yanke shawarar cewa tunnel ɗin yana zubar da kafofin watsa labarai.
Kwatanta fitowar VPN da relay na TURN
Dukansu suna tura fakiti, shi ya sa ake rikita su, kuma teburin kwatance na sama ya cancanci a karanta shi a jere da jere maimakon a matsayin jerin fasali. Ba da relay abu ne na kowane zama da ake ƙirƙira ta hanyar buƙatar da aka tabbatar; tunnel hanya ce. Ɗaya yana da takaddun shaida da suke ƙarewa, ɗayan yana da adireshin abokin tafiya wanda ko dai ana iya isa gare shi ko a'a.
| Component | What it contributes | What it needs to work | What it cannot do |
|---|---|---|---|
| VPN exit | Changes the observed mapping and the route packets take | A working tunnel and a policy that permits the media transport | Allocate a relay or supply signaling |
| STUN server | Reports the mapped address a peer appears to use | Reachability from the client, on its configured transport | Carry media when a direct path fails |
| TURN server | Relays media through an authenticated allocation | Valid credentials, an allowed transport and sufficient capacity | Fix a missing ICE policy or an unauthorized client |
| Signaling channel | Carries offers, answers and candidate lists | Both peers reaching the same application endpoint | Establish connectivity by itself |
Lambobin tasha suna mai da bambancin tabbatacce. TURN yana saurare a 3478 don UDP da TCP da kuma a 5349 don TLS bisa ga dabi'a, kuma cibiyar sadarwar da ke barin 443 amma ta watsar da waɗannan tashoshi za ta gaza a kira ta relay yayin da bincike ke ci gaba normal. Canza tashar VPN ba ya daidaita kome daga ciki, domin tashoshin da suka fi muhimmanci na sabis ɗin relay ne, ba na tunnel ɗin ba.
Karanta binciken, sannan gwada kiran
Burauza suna nuna bayanan da kake buƙata ba tare da kama fakiti ba. Buɗe shafin bincike na WebRTC na burauzarka, yi kiran, ka karanta takwarar ɗan takara da aka zaɓa maimakon jerin da aka tattara: waɗanne nau'ikan ɗan takara na gida da na nesa aka zaɓa, ta wace hanyar jigila da iyalin adireshi, da kuma ko hanyar kai tsaye ce ko ta relay.
Karatu biyu ya cancanci a san su tun farko. Idan takwarar da aka zaɓa ta gida-zuwa-gida ce a adiresoshin sirri, kafofin watsa labarai suna kan hanyar da za ka iya yin tunani a kanta; idan ta relay-zuwa-relay ce, kiran yana cinye ƙarfin relay kuma ya dogara da samuwar wannan sabis ɗin. Rashin da ya tsaya a “ana dubawa” ba tare da takwarar da aka zaɓa ba yana nufin an tattara ƴan takara amma babu wanda ya wuce gwajin haɗi.
Sannan kwatanta waɗannan ƙarshen biyu a cikin kiran ɗaya yayin da kake canza sharadi ɗaya da aka amince da shi kawai, kuma karɓi sakamakon a kan kafofin watsa labarai ko bayanai na gefe biyu maimakon a kan alamar “an haɗa”. Tattara ɗan takara yana yin nasara a lokuta da yawa waɗanda ba sa ɗaukar ko firam ɗaya na sauti. Maimaita kiran a ɗaya gefen canjin kuma adana duka hotunan bincike biyu, domin kwatanta gudu biyu ya fi ba da bayanai fiye da karanta ko wanne shi kaɗai. Ƙarshen iri ɗaya, codec ɗaya, an canza maɓalli ɗaya.
Aikace-aikacen da ya keɓe manufofin jigilar ICE ɗinsa zuwa relay da gangan yana neman ƴan takarar relay ne kawai. Wannan saitin ba ya ƙirƙirar relay kuma ba ya gyara takaddun shaidar da suka ɓace; yana mai da buƙatar a bayyane, wanda ke da amfani sa'ad da wani ya zargi VPN da manufar da shafin ya zaɓa.
Ka riƙe da'awar sirri a taƙaice kamar yadda hujjojin suke
Bayyanar ɗan takara ya dogara da manufofin burauza da aikace-aikace, ba kan matsayin tunnel kaɗai ba, kuma ƙayyadaddun W3C na haɗin abokin tafiya yana ɗaukar mu'amalar IP a matsayin nata al'amari. Don haka VPN da aka haɗa ba shi da tushe mai ƙarfi don yin alkawarin cewa kira zai bayyana adireshi ɗaya da aka zaɓa kawai. Ma'auratan da ke bayan tunnel ɗaya ma na iya zaɓar hanyar da ba ta taɓa barin mai masaukin ba, wanda a lokaci ɗaya haɓaka sirri ne da ƙuntatawar haɗi.
Abin da za ka iya faɗa daidai ya fi ƙunci kuma ya fi amfani: wace takwarar ɗan takara aka zaɓa, wace hanyar jigila ta ɗauke ta, da kuma ko wannan hanyar ta kasance cikin tunnel ɗin. Rubuta waɗannan gaskiyoyi uku don kiran da ke aiki da wanda ya gaza, kuma bambancin yawanci yana ambaton ɓangaren da ya kamata a gyara.
Da zarar haɗin ya yi aiki, raba aiki daga isa. Asara, jinkiri, layi da MTU duk suna ƙasan ingantaccen takwarar ɗan takara, kuma ɗaukar kira mai tsinke a matsayin gazawar haɗi yana mayar da kai cikin jerin ƴan takara ba dalili.