{"id":1751,"date":"2015-10-23T14:11:04","date_gmt":"2015-10-23T14:11:04","guid":{"rendered":"http:\/\/www.kodcafe.com\/?p=1751"},"modified":"2015-10-23T14:11:04","modified_gmt":"2015-10-23T14:11:04","slug":"firewall-guvenlik-duvari-nedir","status":"publish","type":"post","link":"https:\/\/www.kodcafe.com\/?p=1751","title":{"rendered":"Firewall (G\u00fcvenlik Duvar\u0131) Nedir ?"},"content":{"rendered":"

Firewall nedir?
\nBilgisayar\u0131n\u0131zda veya a\u011f\u0131n\u0131zda gelen \u2013 giden paketlerinizi yaz\u0131l\u0131msal olarak veya donan\u0131msal olarak kontrol eden sistemlerin genel ad\u0131na firewall (G\u00fcvenlik Duvar\u0131) denir.<\/p>\n

\"firewall_diyagram\"<\/a>
\n<\/p>\n

Genellikle firewallar d\u0131\u015far\u0131dan a\u011fa yetkisiz eri\u015fimleri engellemek i\u00e7in d\u00fczenlenir. A\u011fdan d\u0131\u015far\u0131ya eri\u015fim serbest iken d\u0131\u015far\u0131dan a\u011fa eri\u015fim k\u0131s\u0131tlan\u0131r. \u00d6rnek vermek gerekirse Bir binan\u0131n g\u00fcvenlik sisteminde kimlik kartlar\u0131 ile giri\u015fi var iken, kimlik kartlar\u0131 olmayan ki\u015filerin binaya giri\u015fleri sa\u011flanamaz., Ya g\u00fcvenlik\u00e7i koyarak binaya giri\u015fleri denetler yada Manyetik kart ile giri\u015fler sa\u011flan\u0131r. Ayn\u0131 mant\u0131kla firewall sistemi de buna benzerdir.<\/p>\n

 <\/p>\n

F\u0131rewall’un esas amac\u0131 a\u011fa zarar vermek yada s\u0131zmak isteyenleri engellemektir. Genel olarak \u015firketler ve veri merkezleri i\u00e7in firewall s\u0131k\u00e7a kullan\u0131lan bir g\u00fcvenlik metodudur. F\u0131rewallar g\u00fcvenlik ve denetim i\u00e7in bir t\u00fcr ge\u00e7it noktas\u0131 olu\u015fturur. Ayr\u0131ca sisteme modem ile ba\u011flant\u0131 kurulmak istendi\u011finde f\u0131rewall bu ba\u011flant\u0131y\u0131 kontrol edip izleyebilme imkan\u0131na da sahiptir.<\/p>\n

 <\/p>\n

Neden Firewall ihtiyac\u0131m\u0131z var. ? Bilgisayar kullan\u0131c\u0131lar\u0131 sadece vir\u00fcs tehdidi alt\u0131nda de\u011fildirler. \u0130\u015fte firewall larla korunabilece\u011fimiz di\u011fer tehditler:<\/p>\n

\u2022 Remote login – uzaktan eri\u015fim ,
\n\u2022 Aplication backdoors – arkakap\u0131 uygulamalar\u0131
\n\u2022 Dos (denial of service) attacks – Servis reddi ataklar\u0131
\n\u2022 Smtp Session Hijacking – Eposta protokol\u00fc oturum \u00e7al\u0131nmas\u0131
\n\u2022 Operating system bugs – \u0130\u015fletim sistemi hatalar\u0131
\n\u2022 Email bombs – Eposta bombalar\u0131
\n\u2022 Spam – Zararl\u0131 epostalar
\n\u2022 Source rating – Kaynak sapt\u0131rma<\/p>\n

Firewall\u2019lar\u0131 iki \u015fekilde s\u0131n\u0131fland\u0131rabiliriz.\u00a0Firewall sisteminde ya donan\u0131msal yada yaz\u0131l\u0131msal sistemlere ihtiya\u00e7 duyulabilir.
\no Yap\u0131lar\u0131na g\u00f6re firewall\u2019lar
\n1. Donan\u0131msal Firewall
\n2. Yaz\u0131l\u0131msal Firewall
\no Mimarilerine g\u00f6re firewall\u2019lar<\/p>\n

1. Paket filtreleyen
\n2. Proxy
\n3. Network Address Translation (NAT)
\n4. Sald\u0131r\u0131 Tespit
\n5. Kay\u0131t tutma<\/p>\n

F\u0130REWALL DEZAVANTAJLARI<\/p>\n

\u2022 Firewall genellikle a\u011f\u0131n i\u00e7erisinden gelen tehditlere kar\u015f\u0131 koruma sa\u011flamaz.<\/p>\n

\u2022 F\u0131rewall, trojan ve vir\u00fcs t\u00fcr\u00fc DATA i\u00e7eren veri paketlerine kar\u015f\u0131 da a\u011f\u0131 koruyamaz. \u00c7\u00fcnk\u00fc internetten indirilen yada e-mail ile gelen paketler i\u00e7inde vir\u00fcsler kolayl\u0131kla \u015fifre edilebilirler veya s\u0131k\u0131\u015ft\u0131r\u0131labilirler. Firewall vir\u00fcs imzalar\u0131n\u0131 aramak i\u00e7in b\u00f6yle programlar\u0131 taramaz.
\n\u2022 E\u011fer f\u0131rewall taraf\u0131ndan korunan a\u011f\u0131n i\u00e7ine s\u0131n\u0131rs\u0131z modem eri\u015fimi izni verilirse, sald\u0131ran ki\u015filer f\u0131rewall’u rahat\u00e7a ge\u00e7ebilir.<\/p>\n

\u2022 Video ve ses i\u00e7eren IP paketleri de firewall taraf\u0131ndan filtre edilmedi\u011finden ayr\u0131 bir potansiyel tehlike kayna\u011f\u0131d\u0131r.<\/p>\n","protected":false},"excerpt":{"rendered":"

Firewall nedir? Bilgisayar\u0131n\u0131zda veya a\u011f\u0131n\u0131zda gelen \u2013 giden paketlerinizi yaz\u0131l\u0131msal olarak veya donan\u0131msal olarak kontrol eden sistemlerin genel ad\u0131na firewall (G\u00fcvenlik Duvar\u0131) denir.<\/p>\n","protected":false},"author":1,"featured_media":1754,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1,15],"tags":[142],"class_list":["post-1751","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-genel","category-guvenlik","tag-firewall"],"_links":{"self":[{"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=\/wp\/v2\/posts\/1751","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=1751"}],"version-history":[{"count":0,"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=\/wp\/v2\/posts\/1751\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=\/"}],"wp:attachment":[{"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=1751"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=1751"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.kodcafe.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=1751"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}