{"id":48202,"date":"2022-06-25T07:18:04","date_gmt":"2022-06-25T04:18:04","guid":{"rendered":"https:\/\/kutaybilen.com.tr\/?p=48202"},"modified":"2022-06-25T07:18:04","modified_gmt":"2022-06-25T04:18:04","slug":"firewall-guvenlik-duvari-nedir-ne-ise-fayda","status":"publish","type":"post","link":"https:\/\/kutaybilen.com.tr\/?p=48202","title":{"rendered":"Firewall (G\u00fcvenlik Duvar\u0131) Nedir, Ne \u0130\u015fe Fayda?"},"content":{"rendered":"<p>\u0130zledi\u011fim dizinin yeni k\u0131sm\u0131 \u00e7\u0131km\u0131\u015f, gideyim de bol bahis reklaml\u0131 bir siteden izleyeyim dedi\u011finiz anda sizi uyaran o sistem; binlerce dolar olan yaz\u0131l\u0131m\u0131 paras\u0131z indirirken sizi uyaran o dost; bilgisayar\u0131n\u0131z\u0131n tehdit alt\u0131nda oldu\u011funu s\u00f6yleyen o can yolda\u015f\u0131 <strong>firewall yani dijital g\u00fcvenlik duvar\u0131n\u0131zd\u0131r. <\/strong>\u00c7o\u011fu vakit kullan\u0131c\u0131lar taraf\u0131ndan pek \u00f6nemsenmese de firewall hakikaten bir hayat kurtar\u0131c\u0131 olabilir.<\/p>\n<p>En temel tarifiyle <em>firewall; <\/em>a\u011fa gelen giden datalar\u0131 denetim ederek muhtemel tehditleri filtreler ve p\u00fcr\u00fczler. Kullan\u0131lan bu sistem her ge\u00e7en g\u00fcn geli\u015ftiriliyor. Zira kimi muteber kaynaklardan gelen makus niyetli istekler bir\u00e7ok vakit filtreden ge\u00e7meyi ba\u015far\u0131yor. Bu nedenle g\u00fczel bir dijital g\u00fcvenlik duvar\u0131 herkese laz\u0131m. Gelin <strong>firewall nedir, ne i\u015fe fayda, tipleri nelerdir <\/strong>gibi merak edilen sorular\u0131 yak\u0131ndan inceleyelim.<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.webtekno.com\/images\/editor\/default\/0003\/36\/578bfffac40147faaa7014e1d1eab9de5a91e196.jpeg\"\/><\/p>\n<p><b>Firewall nedir?<\/b><\/p>\n<p>Dijital g\u00fcvenlik duvar\u0131 olarak da tan\u0131mlayabilece\u011fimiz firewall; yaz\u0131l\u0131m ve donan\u0131m tabanl\u0131 olarak makul kurallar \u00e7er\u00e7evesinde <strong>a\u011fa gelen ve a\u011fdan giden bilgi paketlerini denetim eden <\/strong>bir a\u011f g\u00fcvenlik sistemidir. A\u011f\u0131 denetim ederken kulland\u0131\u011f\u0131 filtreye ba\u011fl\u0131 olarak her daim internet trafi\u011fini IP filtreleme, port filtreleme, web filtreleme, i\u00e7erik filtreleme \u00fczere denetimlerden ge\u00e7irir.<\/p>\n<p>G\u00fcn\u00fcm\u00fczde i\u015fletim sistemlerinin pek birden fazla kendi yaz\u0131l\u0131m tabanl\u0131 firewall sistemini kullan\u0131r. T\u0131pk\u0131 vakitte a\u011flar ortas\u0131 data aktaran y\u00f6nlendiriciler de <strong>kendi firewall sistemlerine sahiptirler. <\/strong>\u0130nternet ve bilgisayar kullan\u0131m\u0131n\u0131n yayg\u0131nla\u015fmas\u0131 epeyce yeni bir durum olmas\u0131na kar\u015f\u0131n firewall g\u00fcvenlik sistemleri 1980\u2019li y\u0131llarda ortaya \u00e7\u0131km\u0131\u015f bir teknolojidir.<\/p>\n<p><b>Firewall ne i\u015fe fayda?<\/b><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.webtekno.com\/images\/editor\/default\/0003\/36\/ae0d590df1ce7b0a0cf0520eba0eb3bba79f4121.jpeg\"\/><\/p>\n<p>Donan\u0131m ya da yaz\u0131l\u0131m tabanlar\u0131 olarak \u00e7al\u0131\u015fan firewall a\u011f g\u00fcvenlik sistemleri evvelce belirlenmi\u015f bir filtre ile a\u011fa gelen ve giden data paketlerini incelerler. <strong>G\u00fcvenli olmayan kaynaklardan gelen <\/strong>veri paketlerini bu filtreden ge\u00e7irerek m\u00fcmk\u00fcn ataklar\u0131 engellemek temel gayedir.<\/p>\n<p>Firewall a\u011f g\u00fcvenlik sistemleri, harici ayg\u0131tlar ile a\u011f \u00fczerinden bilgi payla\u015f\u0131m\u0131 yap\u0131lan <strong>ba\u011flant\u0131 noktalar\u0131nda bulunurlar. <\/strong>&#8220;Kaynak adresi 172.18.1.1&#8217;in 22 numaral\u0131 ili\u015fki noktas\u0131 \u00fczerinden 172.18.2.1 gayesine ula\u015fmas\u0131na m\u00fcsaade verilir.&#8221; tarifi, bu dijital g\u00fcvenlik duvarlar\u0131n\u0131n yapt\u0131\u011f\u0131 i\u015fi en ger\u00e7ek formda anlatmaktad\u0131r.<\/p>\n<p><b>Firewall nas\u0131l \u00e7al\u0131\u015f\u0131r?<\/b><\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.webtekno.com\/images\/editor\/default\/0003\/36\/a22d59e5dec1d76ebbd4610247c5937f4fbd79b2.jpeg\"\/><\/p>\n<p>Firewall a\u011f g\u00fcvenlik sistemlerinin nas\u0131l \u00e7al\u0131\u015ft\u0131\u011f\u0131n\u0131 anlamak i\u00e7in bir \u00f6rnek \u00fczerinden gidelim; <strong>IP adreslerini meskenler, port numaralar\u0131n\u0131 ise odalar olarak d\u00fc\u015f\u00fcnelim. <\/strong>Eve sadece inan\u00e7l\u0131 bireyler yani inan\u00e7l\u0131 kaynak adresleri girebilir. Konuta giren bireyler bir filtreden daha ge\u00e7erek sadece belli odalara yani ili\u015fki noktalar\u0131na ula\u015fabilirler. Yani firewall filtresi birden \u00e7ok noktada denetim ve denetleme sa\u011flar.<\/p>\n<p>Eski tip paket filtrelemeli firewall g\u00fcvenlik a\u011f sistemleri bu mevzuda biraz zay\u0131ft\u0131. Temel bir filtre \u00fczerinden bilgi paketlerini denetim ediyor ve bazen emniyetli kaynaktan gelen iste\u011fi direkt olarak kabul ediyorlard\u0131. Vakit i\u00e7inde <strong>g\u00fcvenilir bir kaynaktan gelen her iste\u011fin \u00e2l\u00e2 niyetli olmad\u0131\u011f\u0131 anla\u015f\u0131l\u0131nca <\/strong>firewall a\u011f g\u00fcvenlik sistemleri de geli\u015ftirilerek farkl\u0131 cinsler ortaya \u00e7\u0131kt\u0131.<\/p>\n<p><b>Firewall \u00e7e\u015fitleri:<\/b><\/p>\n<ul>\n<li>Next-generation firewalls<\/li>\n<li>Proxy firewalls<\/li>\n<li>Network address translation firewalls<\/li>\n<li>Stateful multilayer inspection firewalls<\/li>\n<\/ul>\n<p><b>Next-generation firewalls:<\/b><\/p>\n<p>Next-generation firewalls, k\u0131saca NGFW, T\u00fcrk\u00e7esi ile yeni ku\u015fak g\u00fcvenlik duvarlar\u0131; klasik filtreleri \u015fifreli trafik kontrol\u00fc, m\u00fcsaadesiz giri\u015f tedbire sistemleri, vir\u00fcsten muhafaza \u00fczere <strong>ek \u00f6zelliklerle desteklerler. <\/strong>Bu sistemlerin en de\u011ferli \u00f6zelli\u011fi ise derin paket incelemesidir. Derin paket incelemesi sayesinde inan\u00e7l\u0131 kaynaklardan gelen isteklere bile ku\u015fkuyla yakla\u015f\u0131l\u0131r ve derinlemesine inceleme yap\u0131l\u0131r. <\/p>\n<p><b>Proxy firewalls:<\/b><\/p>\n<p>Proxy g\u00fcvenlik duvarlar\u0131 uygulama seviyesinde g\u00fcvenli\u011fi denetlerler. Yani ba\u015fkalar\u0131ndan farkl\u0131 olarak <strong>iki sistem ortas\u0131nda kurulan bir k\u00f6pr\u00fc vazifesi g\u00f6r\u00fcrler. <\/strong>Bu sistemde istemci g\u00fcvenlik duvar\u0131na bir istek g\u00f6nderir, istek filtreden ge\u00e7irilir ve duruma nazaran istek onaylan\u0131r ya da engellenir. Proxy, HTTP ve FTP \u00fczere katman protokolleri i\u00e7in trafi\u011fi izleyerek filtreleme yapar ve derin paket incelemesini kullan\u0131r.<\/p>\n<p><img decoding=\"async\" src=\"https:\/\/www.webtekno.com\/images\/editor\/default\/0003\/36\/056727f403c544902a1c44b977f74fc3b5929c18.jpeg\"\/><\/p>\n<p><b>Network address translation firewalls:<\/b><\/p>\n<p>Network address translation firewalls, k\u0131saca NAT, T\u00fcrk\u00e7esi ile a\u011f adresi \u00e7evirisi g\u00fcvenlik duvarlar\u0131; farkl\u0131 a\u011f adreslerine sahip ayg\u0131tlar\u0131n <strong>tek IP adresi \u00fczerinden a\u011fa ba\u011flanmas\u0131na m\u00fcsaade vererek <\/strong>di\u011fer IP adreslerini sakl\u0131 fiyat. Bu sayede IP adresi \u00fczerinden sald\u0131rmak isteyen hacker\u2019lar eli bo\u015f d\u00f6nerler. NAT, bir k\u00fcme bilgisayar ile d\u0131\u015f a\u011f ortas\u0131nda bulunan bir sistem olmas\u0131 nedeniyle Proxy sistemine benzetilir.<\/p>\n<p><b>Stateful multilayer inspection firewalls:<\/b><\/p>\n<p>Stateful multilayer inspection firewalls, k\u0131saca SMLI, T\u00fcrk\u00e7esi ile durum bilgisi olan \u00e7ok katmanl\u0131 kontrol g\u00fcvenlik duvarlar\u0131; <strong>hem a\u011f transferinde hem de uygulama katmanlar\u0131nda bulunan <\/strong>veri paketlerini inceler ve kar\u015f\u0131la\u015ft\u0131rma yaparlar. Kar\u015f\u0131la\u015ft\u0131rma sonucu s\u0131rf inan\u00e7l\u0131 olan paketler sistemi ge\u00e7ebilir. Katman katman filtreleme yapt\u0131\u011f\u0131 i\u00e7in kayna\u011f\u0131n inan\u00e7l\u0131 oldu\u011fundan emin olmak \u00f6ncelikli hedefidir.<\/p>\n<p>\u0130nternet d\u00fcnyas\u0131nda att\u0131\u011f\u0131m\u0131z her ad\u0131mda g\u00fcvenli\u011fimizi sa\u011flayan <strong>firewall nedir, ne i\u015fe fayda, nas\u0131l \u00e7al\u0131\u015f\u0131r, cinsleri nelerdir <\/strong>gibi merak edilen sorular\u0131 yan\u0131tlad\u0131k ve a\u011f g\u00fcvenlik sistemleri hakk\u0131nda bilmeniz gereken de\u011ferli ayr\u0131nt\u0131lardan bahsettik.<\/p>\n<div>  <\/div>\n","protected":false},"excerpt":{"rendered":"<p>\u0130zledi\u011fim dizinin yeni k\u0131sm\u0131 \u00e7\u0131km\u0131\u015f, gideyim de bol bahis reklaml\u0131 bir siteden izleyeyim dedi\u011finiz anda sizi uyaran o sistem; binlerce dolar olan &#8230;<\/p>\n","protected":false},"author":1,"featured_media":48203,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":[],"categories":[854],"tags":[945,2391,6655,1904,1035],"aioseo_notices":[],"_links":{"self":[{"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=\/wp\/v2\/posts\/48202"}],"collection":[{"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=48202"}],"version-history":[{"count":1,"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=\/wp\/v2\/posts\/48202\/revisions"}],"predecessor-version":[{"id":48204,"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=\/wp\/v2\/posts\/48202\/revisions\/48204"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=\/wp\/v2\/media\/48203"}],"wp:attachment":[{"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=48202"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=48202"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/kutaybilen.com.tr\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=48202"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}