
{"id":940,"date":"2012-01-23T07:45:14","date_gmt":"2012-01-23T07:45:14","guid":{"rendered":"http:\/\/congnghepc.com\/2012\/01\/23\/bao-mat-wi-fi-tu-nhung-buoc-co-ban\/"},"modified":"2012-01-23T07:45:14","modified_gmt":"2012-01-23T07:45:14","slug":"bao-mat-wi-fi-tu-nhung-buoc-co-ban","status":"publish","type":"post","link":"https:\/\/tapchicntt.com\/bao-mat-wi-fi-tu-nhung-buoc-co-ban\/","title":{"rendered":"B\u1ea3o m\u1eadt Wi-Fi t\u1eeb nh\u1eefng b\u01b0\u1edbc c\u01a1 b\u1ea3n"},"content":{"rendered":"<p style=\"text-align: center;\">\n\t<img decoding=\"async\" alt=\"B\u1ea3o m\u1eadt Wi-Fi t\u1eeb nh\u1eefng b\u01b0\u1edbc c\u01a1 b\u1ea3n\" src=\"http:\/\/dl.dropbox.com\/u\/1552467\/pctips\/2012\/bao-mat-wi-fi-tu-nhung-buoc-co-ban\/SecureWifi.jpg\" style=\"width: 500px; height: 266px;\" \/><\/p>\n<h2>\n\t1. Kh&ocirc;ng n&ecirc;n s\u1eed d\u1ee5ng WEP<\/h2>\n<p style=\"text-align: justify;\">\n\tB\u1ea3o m\u1eadt WEP (wired equivalent privacy) t\u1eeb l&acirc;u \u0111&atilde; ch\u1ebft. Kh\u1ea3 n\u0103ng m&atilde; h&oacute;a c\u1ee7a n&oacute; c&oacute; th\u1ec3 d\u1ec5 d&agrave;ng v&agrave; nhanh ch&oacute;ng b\u1ecb ph&aacute; v\u1ee1 b\u1edfi h\u1ea7u h\u1ebft c&aacute;c hacker kh&ocirc;ng chuy&ecirc;n. Do v\u1eady, b\u1ea1n kh&ocirc;ng n&ecirc;n s\u1eed d\u1ee5ng WEP m\u1ed9t ch&uacute;t n&agrave;o c\u1ea3. N\u1ebfu \u0111ang s\u1eed d\u1ee5ng, h&atilde;y n&acirc;ng c\u1ea5p ngay l&ecirc;n WPA2 (Wi-Fi protected access) v\u1edbi ch\u1ee9ng th\u1ef1c 802.1X. N\u1ebfu m\u1edbi \u0111\u01b0\u1ee3c cho m\u1ed9t chi\u1ebfc router wifi ho\u1eb7c access point kh&ocirc;ng h\u1ed7 tr\u1ee3 WPA2, h&atilde;y th\u1eed c\u1eadp nh\u1eadt firmware ho\u1eb7c \u0111\u01a1n gi\u1ea3n nh\u1ea5t l&agrave; thay thi\u1ebft b\u1ecb m\u1edbi.<\/p>\n<h2>\n\t2. Kh&ocirc;ng n&ecirc;n s\u1eed d\u1ee5ng WPA\/WPA2-PSK<\/h2>\n<p style=\"text-align: justify;\">\n\tCh\u1ebf \u0111\u1ed9 <strong>pre-shared key<\/strong> (PSK) c\u1ee7a WPA v&agrave; WPA2 kh&ocirc;ng \u0111\u01b0\u1ee3c b\u1ea3o m\u1eadt \u0111\u1ed1i v\u1edbi m&ocirc;i tr\u01b0\u1eddng doanh nghi\u1ec7p cho l\u1eafm. Khi s\u1eed d\u1ee5ng ch\u1ebf \u0111\u1ed9 n&agrave;y, c\u1ea7n ph\u1ea3i \u0111i\u1ec1n key PSK cho m\u1ed7i thi\u1ebft b\u1ecb ph&aacute;t wifi. Do \u0111&oacute;, key n&agrave;y c\u1ea7n \u0111\u01b0\u1ee3c thay \u0111\u1ed5i m\u1ed7i l\u1ea7n m\u1ed9t nh&acirc;n vi&ecirc;n r\u1eddi kh\u1ecfi c&ocirc;ng ty v&agrave; khi m\u1ed9t thi\u1ebft b\u1ecb ph&aacute;t b\u1ecb m\u1ea5t ho\u1eb7c b\u1ecb tr\u1ed9m &ndash; nh\u1eefng \u0111i\u1ec1u v\u1eabn ch\u01b0a th\u1ef1c s\u1ef1 \u0111\u01b0\u1ee3c ch&uacute; tr\u1ecdng v\u1edbi h\u1ea7u h\u1ebft c&aacute;c m&ocirc;i tr\u01b0\u1eddng doanh nghi\u1ec7p.<\/p>\n<h2>\n\t3. Tri\u1ec3n khai 802.11i<\/h2>\n<p style=\"text-align: justify;\">\n\tCh\u1ebf \u0111\u1ed9 EAP (extensible authentication protocol) c\u1ee7a b\u1ea3o m\u1eadt WPA v&agrave; WPA2 s\u1eed d\u1ee5ng ch\u1ee9ng th\u1ef1c 802.1X thay v&igrave; d&ugrave;ng PSKs, cung c\u1ea5p cho kh\u1ea3 n\u0103ng \u0111\u01b0a cho m\u1ed7i ng\u01b0\u1eddi d&ugrave;ng ho\u1eb7c thi\u1ebft b\u1ecb m\u1ed9t th&ocirc;ng tin \u0111\u0103ng nh\u1eadp ri&ecirc;ng: t&ecirc;n ng\u01b0\u1eddi d&ugrave;ng v&agrave; m\u1eadt kh\u1ea9u ho\u1eb7c m\u1ed9t ch\u1ee9ng th\u1ef1c \u0111i\u1ec7n t\u1eed.<\/p>\n<p style=\"text-align: justify;\">\n\tC&aacute;c key m&atilde; h&oacute;a th\u1ef1c s\u1ef1 s\u1ebd th\u01b0\u1eddng xuy&ecirc;n \u0111\u01b0\u1ee3c thay \u0111\u1ed5i v&agrave; trao \u0111\u1ed5i &ldquo;&acirc;m th\u1ea7m&rdquo; trong background. Do \u0111&oacute;, n\u1ebfu mu\u1ed1n thay \u0111\u1ed5i ho\u1eb7c c&oacute; thay \u0111\u1ed5i v\u1ec1 nh&acirc;n s\u1ef1, t\u1ea5t c\u1ea3 nh\u1eefng g&igrave; b\u1ea1n c\u1ea7n ph\u1ea3i l&agrave;m l&agrave; \u0111i\u1ec1u ch\u1ec9nh th&ocirc;ng tin \u0111\u0103ng nh\u1eadp \u1edf server t\u1eadp trung, thay v&igrave; thay \u0111\u1ed5i PSK \u1edf m\u1ed7i thi\u1ebft b\u1ecb. Key PSK c\u0169ng ng\u0103n ch\u1eb7n ng\u01b0\u1eddi d&ugrave;ng kh\u1ecfi vi\u1ec7c nghe tr\u1ed9m l\u01b0u l\u01b0\u1ee3ng m\u1ea1ng c\u1ee7a ng\u01b0\u1eddi kh&aacute;c &ndash; m\u1ed9t c&ocirc;ng vi\u1ec7c r\u1ea5t d\u1ec5 th\u1ef1c hi\u1ec7n v\u1edbi nh\u1eefng c&ocirc;ng c\u1ee5 nh\u01b0 add-on <strong>Firesheep <\/strong>c\u1ee7a <a href=\"http:\/\/download.com.vn\/internet+email+tools\/web+browser\/14542_mozilla-firefox.aspx\" target=\"_blank\">Mozilla Firefox<\/a> hay \u1ee9ng d\u1ee5ng <strong>DroidSheep <\/strong>d&agrave;nh cho Google Android.<\/p>\n<p style=\"text-align: center;\">\n\t<img decoding=\"async\" alt=\"B\u1ea3o m\u1eadt Wi-Fi t\u1eeb nh\u1eefng b\u01b0\u1edbc c\u01a1 b\u1ea3n\" src=\"http:\/\/dl.dropbox.com\/u\/1552467\/pctips\/2012\/bao-mat-wi-fi-tu-nhung-buoc-co-ban\/SecureWifi3.jpg\" style=\"width: 280px; height: 238px;\" \/><\/p>\n<p style=\"text-align: justify;\">\n\tH&atilde;y nh\u1edb trong \u0111\u1ea7u r\u1eb1ng, \u0111\u1ec3 c&oacute; \u0111\u01b0\u1ee3c b\u1ea3o m\u1eadt cao nh\u1ea5t c&oacute; th\u1ec3, b\u1ea1n n&ecirc;n s\u1eed d\u1ee5ng WPA2 v\u1edbi 802.1X, hay 802.11i.<\/p>\n<p style=\"text-align: justify;\">\n\t\u0110\u1ec3 k&iacute;ch ho\u1ea1t ch\u1ee9ng th\u1ef1c 802.1X, b\u1ea1n c\u1ea7n ph\u1ea3i c&oacute; m\u1ed9t server RADIUS\/AAA. N\u1ebfu \u0111ang ch\u1ea1y Windows Server 2008 ho\u1eb7c cao h\u01a1n, h&atilde;y c&acirc;n nh\u1eafc s\u1eed d\u1ee5ng Network Policy Server (NPS) ho\u1eb7c Internet Authenticate Service (IAS) (hay phi&ecirc;n b\u1ea3n server tr\u01b0\u1edbc \u0111&oacute;). N\u1ebfu b\u1ea1n kh&ocirc;ng ch\u1ea1y Windows Server, b\u1ea1n c&oacute; th\u1ec3 s\u1eed d\u1ee5ng server m&atilde; ngu\u1ed3n m\u1edf FreeRADIUS.<\/p>\n<p style=\"text-align: justify;\">\n\tB\u1ea1n c&oacute; th\u1ec3 &aacute;p d\u1ee5ng c&agrave;i \u0111\u1eb7t 802.1X cho c&aacute;c thi\u1ebft b\u1ecb qua Group Policy n\u1ebfu \u0111ang ch\u1ea1y Windows Server 2008 R2. N\u1ebfu kh&ocirc;ng, h&atilde;y th\u1eed c&acirc;n nh\u1eafc s\u1eed d\u1ee5ng m\u1ed9t gi\u1ea3i ph&aacute;p b&ecirc;n th\u1ee9 3 n&agrave;o \u0111&oacute; \u0111\u1ec3 c\u1ea5u h&igrave;nh thi\u1ebft b\u1ecb.<\/p>\n<h2>\n\t4. Th\u1ef1c hi\u1ec7n c&agrave;i \u0111\u1eb7t b\u1ea3o m\u1eadt 802.1X<\/h2>\n<p style=\"text-align: justify;\">\n\tCh\u1ebf \u0111\u1ed9 EPA c\u1ee7a WPA\/WPA2 v\u1eabn c&oacute; kh\u1ea3 n\u0103ng b\u1ecb t\u1ea5n c&ocirc;ng b\u1edfi c&aacute;c hacker b&aacute;n chuy&ecirc;n. Tuy nhi&ecirc;n, b\u1ea1n c&oacute; th\u1ec3 ng\u0103n ch\u1eb7n ch&uacute;ng t\u1ea5n c&ocirc;ng b\u1eb1ng c&aacute;ch b\u1ea3o m\u1eadt c&agrave;i \u0111\u1eb7t EAP cho thi\u1ebft b\u1ecb. V&iacute; d\u1ee5, trong c&agrave;i \u0111\u1eb7t EAP cho Windows, b\u1ea1n c&oacute; th\u1ec3 k&iacute;ch ho\u1ea1t ch\u1ebf \u0111\u1ed9 x&aacute;c nh\u1eadn ch\u1ee9ng th\u1ef1c server b\u1eb1ng c&aacute;ch ch\u1ecdn ch\u1ee9ng th\u1ef1c CA, g&aacute;n \u0111\u1ecba ch\u1ec9 server v&agrave; disable n&oacute; kh\u1ecfi vi\u1ec7c h\u1ecfi ng\u01b0\u1eddi d&ugrave;ng trust server m\u1edbi ho\u1eb7c x&aacute;c th\u1ef1c CA.<\/p>\n<p style=\"text-align: justify;\">\n\tB\u1ea1n c&oacute; th\u1ec3 &aacute;p d\u1ee5ng c&agrave;i \u0111\u1eb7t 802.1X cho c&aacute;c thi\u1ebft b\u1ecb qua Group Policy ho\u1eb7c s\u1eed d\u1ee5ng gi\u1ea3i ph&aacute;p b&ecirc;n th\u1ee9 3, v&iacute; nh\u01b0 Quick1X c\u1ee7a Avenda.<\/p>\n<h2>\n\t5. N&ecirc;n s\u1eed d\u1ee5ng m\u1ed9t h\u1ec7 th\u1ed1ng ng\u0103n ch\u1eb7n x&acirc;m nh\u1eadp tr&aacute;i ph&eacute;p v&agrave;o m\u1ea1ng kh&ocirc;ng d&acirc;y<\/h2>\n<p style=\"text-align: justify;\">\n\tB\u1ea3o m\u1eadt m\u1ea1ng kh&ocirc;ng d&acirc;y l&agrave; \u0111i\u1ec1u n&ecirc;n l&agrave;m thay v&igrave; t\u1eadp trung v&agrave;o \u0111&aacute;nh b\u1ea1i nh\u1eefng k\u1ebb c\u1ed1 g\u1eafng chi\u1ebfm quy\u1ec1n truy c\u1eadp v&agrave;o m\u1ea1ng c\u1ee7a b\u1ea1n. V&iacute; d\u1ee5, hacker c&oacute; th\u1ec3 thi\u1ebft l\u1eadp m\u1ed9t \u0111i\u1ec3m truy c\u1eadp \u1ea3o ho\u1eb7c th\u1ef1c hi\u1ec7n t\u1ea5n c&ocirc;ng <a href=\"http:\/\/www.quantrimang.com.vn\/baomat\/hacker\/78844_Tan-cong-DDoS-hung-than-cua-cac-trang-web.aspx\" target=\"_blank\">DOS <\/a>&ndash; denial-of-service. \u0110\u1ec3 c&oacute; \u0111\u01b0\u1ee3c kh\u1ea3 n\u0103ng d&ograve; t&igrave;m v&agrave; \u0111&aacute;nh b\u1ea1i nh\u1eefng ki\u1ec3u t\u1ea5n c&ocirc;ng nh\u01b0 v\u1eady, b\u1ea1n n&ecirc;n tri\u1ec3n khai m\u1ed9t h\u1ec7 th\u1ed1ng ng\u0103n ch\u1eb7n x&acirc;m nh\u1eadp m\u1ea1ng kh&ocirc;ng d&acirc;y (WIPS). Thi\u1ebft k\u1ebf v&agrave; ph\u01b0\u01a1ng ph&aacute;p \u0111\u01b0\u1ee3c s\u1eed d\u1ee5ng trong WIPS kh&aacute;c bi\u1ec7t theo t\u1eebng nh&agrave; s\u1ea3n xu\u1ea5t nh\u01b0ng nh&igrave;n chung ch&uacute;ng c&oacute; th\u1ec3 gi&aacute;m s&aacute;t m\u1ea1ng, th&ocirc;ng b&aacute;o cho ng\u01b0\u1eddi d&ugrave;ng v&agrave; c&oacute; th\u1ec3 ng\u0103n ch\u1eb7n \u0111i\u1ec3m truy c\u1eadp \u1ea3o hay c&aacute;c ho\u1ea1t \u0111\u1ed9ng m&atilde; \u0111\u1ed9c.<\/p>\n<p style=\"text-align: center;\">\n\t<img decoding=\"async\" alt=\"B\u1ea3o m\u1eadt Wi-Fi t\u1eeb nh\u1eefng b\u01b0\u1edbc c\u01a1 b\u1ea3n\" src=\"http:\/\/dl.dropbox.com\/u\/1552467\/pctips\/2012\/bao-mat-wi-fi-tu-nhung-buoc-co-ban\/SecureWifi4.jpg\" style=\"width: 486px; height: 328px;\" \/><\/p>\n<p style=\"text-align: justify;\">\n\tC&oacute; r\u1ea5t nhi\u1ec1u nh&agrave; s\u1ea3n xu\u1ea5t hi\u1ec7n \u0111ang cung c\u1ea5p gi\u1ea3i ph&aacute;p WIPS, v&iacute; nh\u01b0 AirMagnet v&agrave; AirTight Neworks. B\u1ea1n c\u0169ng c&oacute; th\u1ec3 t&igrave;m t\u1edbi c&aacute;c s\u1ea3n ph\u1ea9m m&atilde; ngu\u1ed3n m\u1edf, ti&ecirc;u bi\u1ec3u l&agrave; <a href=\"http:\/\/download.com.vn\/security+firewall+tools\/22939_snort-for-linux.aspx\" target=\"_blank\">Snort<\/a>.<\/p>\n<h2>\n\t6. N&ecirc;n tri\u1ec3n khai NAP ho\u1eb7c NAC<\/h2>\n<p style=\"text-align: justify;\">\n\tNgo&agrave;i vi\u1ec7c s\u1eed d\u1ee5ng 802.11i v&agrave; WIPS, b\u1ea1n n&ecirc;n c&acirc;n nh\u1eafc t\u1edbi vi\u1ec7c tri\u1ec3n khai gi\u1ea3i ph&aacute;p Network Access Protection (NAP &ndash; b\u1ea3o v\u1ec7 truy c\u1eadp m\u1ea1ng) ho\u1eb7c Network Access Control (NAC &ndash; qu\u1ea3n l&yacute; truy c\u1eadp m\u1ea1ng). Ch&uacute;ng s\u1ebd cung c\u1ea5p th&ecirc;m kh\u1ea3 n\u0103ng qu\u1ea3n l&yacute; truy c\u1eadp m\u1ea1ng, d\u1ef1a v&agrave;o nh\u1eadn d\u1ea1ng thi\u1ebft b\u1ecb v\u1edbi c&aacute;c policy \u0111&atilde; \u0111\u01b0\u1ee3c \u0111\u1eb7t tr\u01b0\u1edbc. Ch&uacute;ng c\u0169ng bao g\u1ed3m m\u1ed9t ch\u1ee9c n\u0103ng \u0111\u1ec3 c&aacute;ch ly nh\u1eefng thi\u1ebft b\u1ecb c&oacute; v\u1ea5n \u0111\u1ec1 v&agrave; s\u1eeda ch\u1eefa \u0111\u1ec3 thi\u1ebft b\u1ecb c&oacute; th\u1ec3 nhanh ch&oacute;ng quay tr\u1edf l\u1ea1i l&agrave;m vi\u1ec7c.<\/p>\n<p style=\"text-align: justify;\">\n\tM\u1ed9t s\u1ed1 gi\u1ea3i ph&aacute;p NAC c&oacute; kh\u1ea3 n\u0103ng bao g\u1ed3m ch\u1ee9c n\u0103ng d&ograve; t&igrave;m v&agrave; ng\u0103n ch\u1eb7n x&acirc;m nh\u1eadp v&agrave;o m\u1ea1ng, nh\u01b0ng b\u1ea1n s\u1ebd ph\u1ea3i ki\u1ec3m tra xem n&oacute; c&oacute; cung c\u1ea5p kh\u1ea3 n\u0103ng chuy&ecirc;n bi\u1ec7t v\u1ec1 b\u1ea3o v\u1ec7 m\u1ea1ng kh&ocirc;ng d&acirc;y hay kh&ocirc;ng.<\/p>\n<p style=\"text-align: justify;\">\n\tN\u1ebfu \u0111ang ch\u1ea1y Windows Server 2008 tr\u1edf l&ecirc;n v&agrave; Windows Vista\/7 \u0111\u1ed1i v\u1edbi thi\u1ebft b\u1ecb, b\u1ea1n c&oacute; th\u1ec3 s\u1eed d\u1ee5ng ch\u1ee9c n\u0103ng NAP c\u1ee7a Microsoft. N\u1ebfu kh&ocirc;ng, h&atilde;y t&igrave;m t\u1edbi nh\u1eefng gi\u1ea3i ph&aacute;p do b&ecirc;n th\u1ee9 3 cung c\u1ea5p, v&iacute; nh\u01b0 PacketFence.<\/p>\n<h2>\n\t7. Kh&ocirc;ng n&ecirc;n tin t\u01b0\u1edfng SSID \u1ea9n<\/h2>\n<p style=\"text-align: justify;\">\n\tM\u1ed9t trong nh\u1eefng l\u1eddi \u0111\u1ed3n v\u1ec1 b\u1ea3o m\u1eadt m\u1ea1ng kh&ocirc;ng d&acirc;y l&agrave; disable truy\u1ec1n ph&aacute;t SSID c\u1ee7a c&aacute;c \u0111i\u1ec3m truy c\u1eadp s\u1ebd gi&uacute;p \u1ea9n m\u1ea1ng c\u1ee7a b\u1ea1n hay &iacute;t nh\u1ea5t l&agrave; t\u1ea1o SSID an to&agrave;n khi\u1ebfn hacker kh&oacute; ph&aacute;. Tuy nhi&ecirc;n, c&aacute;ch n&agrave;y ch\u1ec9 gi&uacute;p g\u1ee1 b\u1ecf SSID kh\u1ecfi \u0111i\u1ec3m truy c\u1eadp. N&oacute; v\u1eabn c&oacute; trong ch\u1ee9a y&ecirc;u c\u1ea7u 802.11 v&agrave; trong m\u1ed9t s\u1ed1 tr\u01b0\u1eddng h\u1ee3p, n&oacute; c&ograve;n c&oacute; trong y&ecirc;u c\u1ea7u d&ograve; m\u1ea1ng v&agrave; c&aacute;c g&oacute;i tr\u1ea3 l\u1eddi. Do \u0111&oacute;, m\u1ed9t hacker hay k\u1ebb nghe l&eacute;n n&agrave;o \u0111&oacute; c&oacute; th\u1ec3 d\u1ec5 d&agrave;ng v&agrave; nhanh ch&oacute;ng ph&aacute;t hi\u1ec7n ra SSID \u1ea9n &ndash; \u0111\u1eb7c bi\u1ec7t l&agrave; \u1edf m\u1ea1ng b\u1eadn &ndash; v\u1edbi t&iacute;nh n\u0103ng ph&acirc;n t&iacute;ch m\u1ea1ng kh&ocirc;ng d&acirc;y h\u1ee3p ph&aacute;p.<\/p>\n<p style=\"text-align: justify;\">\n\tM\u1ed9t s\u1ed1 ng\u01b0\u1eddi tranh lu\u1eadn l&agrave; t\u1eaft truy\u1ec1n ph&aacute;t SSID v\u1eabn cung c\u1ea5p th&ecirc;m t\u1ea7ng b\u1ea3o m\u1eadt cho m\u1ea1ng, nh\u01b0ng b\u1ea1n c\u0169ng h&atilde;y nh\u1edb lu&ocirc;n r\u1eb1ng n&oacute; c&oacute; kh\u1ea3 n\u0103ng g&acirc;y ra \u1ea3nh h\u01b0\u1edfng ti&ecirc;u c\u1ef1c l&ecirc;n c\u1ea5u h&igrave;nh v&agrave; kh\u1ea3 n\u0103ng th\u1ef1c hi\u1ec7n c\u1ee7a m\u1ea1ng. B\u1ea1n s\u1ebd ph\u1ea3i nh\u1eadp th\u1ee7 c&ocirc;ng SSID v&agrave;o c&aacute;c thi\u1ebft b\u1ecb, ti\u1ebfp \u0111\u1ebfn l&agrave; c\u1ea5u h&igrave;nh thi\u1ebft b\u1ecb. N&oacute; c\u0169ng c&oacute; th\u1ec3 g&acirc;y ra vi\u1ec7c t\u0103ng nh\u1eefng y&ecirc;u c\u1ea7u th\u0103m d&ograve; v&agrave; g&oacute;i tin tr\u1ea3 v\u1ec1, gi\u1ea3m l\u01b0\u1ee3ng b\u0103ng th&ocirc;ng hi\u1ec7n c&oacute;.<\/p>\n<h2>\n\t8. Kh&ocirc;ng n&ecirc;n tin t\u01b0\u1edfng l\u1ecdc \u0111\u1ecba ch\u1ec9 MAC<\/h2>\n<p style=\"text-align: justify;\">\n\tL\u1eddi \u0111\u1ed3n kh&aacute;c v\u1ec1 b\u1ea3o m\u1eadt m\u1ea1ng kh&ocirc;ng d&acirc;y l&agrave; k&iacute;ch ho\u1ea1t t&iacute;nh n\u0103ng l\u1ecdc \u0111\u1ecba ch\u1ec9 MAC s\u1ebd gi&uacute;p c&oacute; th&ecirc;m \u0111\u01b0\u1ee3c m\u1ed9t t\u1ea7ng b\u1ea3o m\u1eadt, qu\u1ea3n l&yacute; c&aacute;c \u1ee9ng d\u1ee5ng k\u1ebft n\u1ed1i v\u1edbi m\u1ea1ng. \u0110i\u1ec1u n&agrave;y c&oacute; \u0111&ocirc;i ch&uacute;t ch&iacute;nh x&aacute;c, nh\u01b0ng h&atilde;y nh\u1edb r\u1eb1ng hacker c&oacute; th\u1ec3 d\u1ec5 d&agrave;ng theo d&otilde;i m\u1ea1ng c\u1ee7a b\u1ea1n \u0111\u1ec3 l\u1ea5y \u0111\u1ecba ch\u1ec9 MAC h\u1ee3p ph&aacute;p, sau \u0111&oacute; ch&uacute;ng s\u1ebd thay \u0111\u1ed5i \u0111\u1ecba ch\u1ec9 Mac cho m&aacute;y c\u1ee7a ch&uacute;ng.<\/p>\n<p style=\"text-align: center;\">\n\t<img decoding=\"async\" alt=\"B\u1ea3o m\u1eadt Wi-Fi t\u1eeb nh\u1eefng b\u01b0\u1edbc c\u01a1 b\u1ea3n\" src=\"http:\/\/dl.dropbox.com\/u\/1552467\/pctips\/2012\/bao-mat-wi-fi-tu-nhung-buoc-co-ban\/SecureWifi5.jpg\" style=\"width: 352px; height: 304px;\" \/><\/p>\n<p style=\"text-align: justify;\">\n\tDo v\u1eady, b\u1ea1n kh&ocirc;ng n&ecirc;n tri\u1ec3n khai kh\u1ea3 n\u0103ng l\u1ecdc \u0111\u1ecba ch\u1ec9 MAC v\u1edbi suy ngh\u0129 ch&uacute;ng s\u1ebd gi&uacute;p &iacute;ch cho b\u1ea3o m\u1eadt c\u1ee7a m&igrave;nh, nh\u01b0ng c&oacute; th\u1ec3 l&agrave; m\u1ed9t c&aacute;ch qu\u1ea3n l&yacute; c&aacute;c thi\u1ebft b\u1ecb, m&aacute;y t&iacute;nh ng\u01b0\u1eddi d&ugrave;ng cu\u1ed1i mang \u0111\u1ebfn c&ocirc;ng ty v&agrave; k\u1ebft n\u1ed1i v\u1edbi m\u1ea1ng. B\u1ea1n c\u0169ng n&ecirc;n ch&uacute; &yacute; t\u1edbi nh\u1eefng v\u1ea5n \u0111\u1ec1 qu\u1ea3n l&yacute; c&oacute; kh\u1ea3 n\u0103ng n\u1ea3y sinh \u0111\u1ec3 gi\u1eef cho danh s&aacute;ch MAC lu&ocirc;n \u0111\u01b0\u1ee3c c\u1eadp nh\u1eadt.<\/p>\n<h2>\n\t9. N&ecirc;n h\u1ea1n ch\u1ebf ng\u01b0\u1eddi d&ugrave;ng SSID c&oacute; th\u1ec3 k\u1ebft n\u1ed1i<\/h2>\n<p style=\"text-align: justify;\">\n\tR\u1ea5t nhi\u1ec1u nh&acirc;n vi&ecirc;n qu\u1ea3n tr\u1ecb m\u1ea1ng \u0111&atilde; b\u1ecf qua m\u1ed9t nguy c\u01a1 c&oacute; v\u1ebb nh\u01b0 \u0111\u01a1n gi\u1ea3n nh\u01b0ng l\u1ea1i c&oacute; \u0111\u1ed9 nguy hi\u1ec3m cao: ng\u01b0\u1eddi d&ugrave;ng nh\u1eadn th\u1ee9c \u0111\u01b0\u1ee3c ho\u1eb7c kh&ocirc;ng nh\u1eadn th\u1ee9c \u0111\u01b0\u1ee3c vi\u1ec7c k\u1ebft n\u1ed1i t\u1edbi m\u1ea1ng kh&ocirc;ng d&acirc;y c\u1ee7a h&agrave;ng x&oacute;m ho\u1eb7c \u0111i\u1ec3m truy c\u1eadp kh&ocirc;ng r&otilde; r&agrave;ng, m\u1edf ra c\u01a1 h\u1ed9i x&acirc;m nh\u1eadp v&agrave;o m&aacute;y \u0111\u1ed1i cho hacker. Tuy nhi&ecirc;n, l\u1ecdc SSID l&agrave; m\u1ed9t c&aacute;ch c&oacute; kh\u1ea3 n\u0103ng ng\u0103n ch\u1eb7n \u0111\u01b0\u1ee3c vi\u1ec7c n&agrave;y. V&iacute; d\u1ee5, trong Windows Vista (hay c&aacute;c phi&ecirc;n b\u1ea3n cao h\u01a1n), b\u1ea1n c&oacute; th\u1ec3 s\u1eed d\u1ee5ng l\u1ec7nh netsh wlan \u0111\u1ec3 th&ecirc;m b\u1ed9 l\u1ecdc v&agrave;o nh\u1eefng ng\u01b0\u1eddi d&ugrave;ng SSID mu\u1ed1n xem v&agrave; k\u1ebft n\u1ed1i. \u0110\u1ed1i v\u1edbi m&aacute;y t&iacute;nh \u0111\u1ec3 b&agrave;n, b\u1ea1n c&oacute; th\u1ec3 t\u1eeb ch\u1ed1i t\u1ea5t c\u1ea3 c&aacute;c SSID ngo\u1ea1i tr\u1eeb m\u1ea1ng c\u1ee7a c&ocirc;ng ty. \u0110\u1ed1i v\u1edbi m&aacute;y x&aacute;ch tay, nh&acirc;n vi&ecirc;n IT ch\u1ec9 c&oacute; kh\u1ea3 n\u0103ng t\u1eeb ch\u1ed1i SSID c\u1ee7a m\u1ea1ng h&agrave;ng x&oacute;m, cho ph&eacute;p ch&uacute;ng v\u1eabn k\u1ebft n\u1ed1i v\u1edbi \u0111i\u1ec3m truy c\u1eadp hay m\u1ea1ng gia \u0111&igrave;nh.<\/p>\n<h2>\n\t10. N&ecirc;n b\u1ea3o v\u1ec7 c&aacute;c thi\u1ebft b\u1ecb m\u1ea1ng<\/h2>\n<p style=\"text-align: justify;\">\n\tH&atilde;y nh\u1edb, b\u1ea3o m\u1eadt m&aacute;y t&iacute;nh kh&ocirc;ng ph\u1ea3i l&agrave; c&ocirc;ng ngh\u1ec7 v&agrave; m&atilde; h&oacute;a m\u1edbi nh\u1ea5t. B\u1ea3o v\u1ec7 v\u1eadt l&yacute; cho c&aacute;c thi\u1ebft b\u1ecb m\u1ea1ng c\u0169ng r\u1ea5t quan tr\u1ecdng. H&atilde;y ch\u1eafc ch\u1eafn r\u1eb1ng c&aacute;c thi\u1ebft b\u1ecb access point \u0111\u01b0\u1ee3c \u0111\u1eb7t xa kh\u1ecfi t\u1ea7m v\u1edbi, v&iacute; nh\u01b0 \u1edf tr&ecirc;n tr\u1ea7n gi\u1ea3 ho\u1eb7c th\u1eadm ch&iacute; l&agrave; cho n&oacute; v&agrave;o m\u1ed9t v\u1ecb tr&iacute; an to&agrave;n r\u1ed3i s\u1eed d\u1ee5ng \u0103ng ten \u0111\u1ec3 c&oacute; \u0111\u01b0\u1ee3c s&oacute;ng t\u1ed1i \u01b0u. N\u1ebfu kh&ocirc;ng \u0111\u01b0\u1ee3c b\u1ea3o m\u1eadt, ai \u0111&oacute; c&oacute; th\u1ec3 d\u1ec5 d&agrave;ng c&agrave;i \u0111\u1eb7t l\u1ea1i access point v\u1ec1 v\u1edbi c&agrave;i \u0111\u1eb7t g\u1ed1c c\u1ee7a nh&agrave; s\u1ea3n xu\u1ea5t \u0111\u1ec3 m\u1edf truy c\u1eadp.<\/p>\n<h2>\n\t11. \u0110\u1eebng qu&ecirc;n b\u1ea3o v\u1ec7 c&aacute;c thi\u1ebft b\u1ecb di \u0111\u1ed9ng<\/h2>\n<p style=\"text-align: justify;\">\n\tC&aacute;c m\u1ed1i lo ng\u1ea1i v\u1ec1 b\u1ea3o m\u1eadt m\u1ea1ng kh&ocirc;ng d&acirc;y kh&ocirc;ng ch\u1ec9 d\u1eebng \u1edf \u0111&acirc;y. Ng\u01b0\u1eddi d&ugrave;ng s\u1edf h\u1eefu smartphone, m&aacute;y x&aacute;ch tay v&agrave; m&aacute;y t&iacute;nh b\u1ea3ng c&oacute; th\u1ec3 \u0111\u01b0\u1ee3c b\u1ea3o v\u1ec7 ngay t\u1ea1i ch\u1ed7. Tuy nhi&ecirc;n, khi h\u1ecd k\u1ebft n\u1ed1i v\u1edbi c&aacute;c \u0111i\u1ec3m truy c\u1eadp Wi-Fi mi\u1ec5n ph&iacute; ho\u1eb7c k\u1ebft n\u1ed1i v\u1edbi router kh&ocirc;ng d&acirc;y gia \u0111&igrave;nh th&igrave; sao? B\u1ea1n n&ecirc;n \u0111\u1ea3m b\u1ea3o r\u1eb1ng c&aacute;c k\u1ebft n\u1ed1i m\u1ea1ng Wi-Fi kh&aacute;c c\u0169ng \u0111\u01b0\u1ee3c b\u1ea3o m\u1eadt nh\u1eb1m ng\u0103n ch\u1eb7n x&acirc;m nh\u1eadp tr&aacute;i ph&eacute;p ho\u1eb7c hacker nghe l&eacute;n.<\/p>\n<p style=\"text-align: center;\">\n\t<img decoding=\"async\" alt=\"B\u1ea3o m\u1eadt Wi-Fi t\u1eeb nh\u1eefng b\u01b0\u1edbc c\u01a1 b\u1ea3n\" src=\"http:\/\/dl.dropbox.com\/u\/1552467\/pctips\/2012\/bao-mat-wi-fi-tu-nhung-buoc-co-ban\/SecureWifi6.jpg\" style=\"width: 498px; height: 445px;\" \/><\/p>\n<p style=\"text-align: justify;\">\n\tD\u1eabu v\u1eady, kh&ocirc;ng d\u1ec5 d&agrave;ng g&igrave; \u0111\u1ec3 ch\u1eafc ch\u1eafn c&aacute;c k\u1ebft n\u1ed1i Wi-Fi ngo&agrave;i lu&ocirc;n \u0111\u01b0\u1ee3c b\u1ea3o m\u1eadt. B\u1ea1n s\u1ebd ph\u1ea3i k\u1ebft h\u1ee3p vi\u1ec7c cung c\u1ea5p, y&ecirc;u c\u1ea7u s\u1eed d\u1ee5ng c&aacute;c gi\u1ea3i ph&aacute;p v&agrave; tuy&ecirc;n truy\u1ec1n cho ng\u01b0\u1eddi d&ugrave;ng v\u1ec1 c&aacute;c nguy c\u01a1 b\u1ea3o m\u1eadt c&ugrave;ng v\u1edbi c&aacute;c ph\u01b0\u01a1ng ph&aacute;p ng\u0103n ch\u1eb7n.<\/p>\n<p style=\"text-align: justify;\">\n\tTr\u01b0\u1edbc h\u1ebft, t\u1ea5t c\u1ea3 c&aacute;c m\u1eabu laptop v&agrave; netbook s\u1ebd ph\u1ea3i k&iacute;ch ho\u1ea1t t\u01b0\u1eddng l\u1eeda c&aacute; nh&acirc;n (v&iacute; nh\u01b0 Windows Firewall) \u0111\u1ec3 ng\u0103n ch\u1eb7n x&acirc;m nh\u1eadp tr&aacute;i ph&eacute;p. B\u1ea1n c&oacute; th\u1ec3 th\u1ef1c thi \u0111i\u1ec1u n&agrave;y qua Group Policy (n\u1ebfu \u0111ang ch\u1ea1y Windows Server) ho\u1eb7c s\u1eed d\u1ee5ng m\u1ed9t gi\u1ea3i ph&aacute;p n&agrave;o \u0111&oacute;, v&iacute; nh\u01b0 Windows Intune \u0111\u1ec3 qu\u1ea3n l&yacute; c&aacute;c m&aacute;y t&iacute;nh kh&ocirc;ng c&oacute; trong mi\u1ec1n.<\/p>\n<p style=\"text-align: justify;\">\n\tTi\u1ebfp \u0111\u1ebfn, b\u1ea1n s\u1ebd ph\u1ea3i ch\u1eafc ch\u1eafn r\u1eb1ng l\u01b0u l\u01b0\u1ee3ng Internet c\u1ee7a ng\u01b0\u1eddi d&ugrave;ng \u0111&atilde; \u0111\u01b0\u1ee3c m&atilde; h&oacute;a khi h\u1ecd \u1edf m\u1ed9t m\u1ea1ng kh&aacute;c b\u1eb1ng c&aacute;ch cung c\u1ea5p truy c\u1eadp VPN v&agrave;o m\u1ea1ng doanh nghi\u1ec7p. N\u1ebfu kh&ocirc;ng mu\u1ed1n s\u1eed d\u1ee5ng VPN trong tr\u01b0\u1eddng h\u1ee3p n&agrave;y, c&oacute; th\u1ec3 c&acirc;n nh\u1eafc t\u1edbi c&aacute;c d\u1ecbch v\u1ee5 kh&aacute;c nh\u01b0 Hotspot Shield ho\u1eb7c Witopia. \u0110\u1ed1i v\u1edbi c&aacute;c thi\u1ebft b\u1ecb iOS (iPhone, iPad, iPod Touch) v&agrave; Android, b\u1ea1n c&oacute; th\u1ec3 s\u1eed d\u1ee5ng \u1ee9ng d\u1ee5ng VPN c\u1ee7a ch&uacute;ng. Tuy nhi&ecirc;n, \u0111\u1ed1i v\u1edbi thi\u1ebft b\u1ecb BlackBerry v&agrave; Windows Phone 7, b\u1ea1n s\u1ebd ph\u1ea3i thi\u1ebft l\u1eadp v&agrave; c\u1ea5u h&igrave;nh server message v\u1edbi thi\u1ebft b\u1ecb n&agrave;y \u0111\u1ec3 c&oacute; th\u1ec3 s\u1eed d\u1ee5ng VPN c\u1ee7a ch&uacute;ng.<\/p>\n<p style=\"text-align: justify;\">\n\tB&ecirc;n c\u1ea1nh \u0111&oacute;, b\u1ea1n c\u0169ng n&ecirc;n \u0111\u1ea3m b\u1ea3o r\u1eb1ng t\u1ea5t c\u1ea3 c&aacute;c d\u1ecbch v\u1ee5 li&ecirc;n quan t\u1edbi m\u1ea1ng \u0111\u1ec1u \u0111\u01b0\u1ee3c b\u1ea3o m\u1eadt, \u0111\u1ec1 ph&ograve;ng tr\u01b0\u1eddng h\u1ee3p ng\u01b0\u1eddi d&ugrave;ng kh&ocirc;ng s\u1eed d\u1ee5ng VPN khi \u0111ang truy c\u1eadp t\u1eeb m\u1ea1ng c&ocirc;ng c\u1ed9ng hay m\u1ed9t m\u1ea1ng kh&ocirc;ng \u0111&aacute;ng tin c\u1eady. V&iacute; d\u1ee5, n\u1ebfu b\u1ea1n cung c\u1ea5p quy\u1ec1n truy c\u1eadp email (qua \u1ee9ng d\u1ee5ng ho\u1eb7c tr&ecirc;n web) \u1edf b&ecirc;n ngo&agrave;i m\u1ea1ng LAN, WAN ho\u1eb7c VPN, h&atilde;y ch\u1eafc ch\u1eafn r\u1eb1ng b\u1ea1n c&oacute; s\u1eed d\u1ee5ng m&atilde; h&oacute;a SSL \u0111\u1ec3 ng\u0103n ch\u1eb7n hacker nghe l&eacute;n v&agrave; tr\u1ed9m th&ocirc;ng tin \u0111\u0103ng nh\u1eadp quan tr\u1ecdng hay c&aacute;c message c&aacute; nh&acirc;n.<\/p>\n","protected":false},"excerpt":{"rendered":"<p style=\"text-align: center;\">\n\t<img decoding=\"async\" alt=\"B\u1ea3o m\u1eadt Wi-Fi t\u1eeb nh\u1eefng b\u01b0\u1edbc c\u01a1 b\u1ea3n\" src=\"http:\/\/dl.dropbox.com\/u\/1552467\/pctips\/2012\/bao-mat-wi-fi-tu-nhung-buoc-co-ban\/SecureWifi.jpg\" style=\"width: 100px; height: 53px; margin-left: 5px; margin-right: 5px; float: left;\" \/><\/p>\n<p>\n\tWi-Fi v\u1ed1n d\u0129 r\u1ea5t d\u1ec5 b\u1ecb t\u1ea5n c&ocirc;ng v&agrave; b\u1ecb nghe l&eacute;n, nh\u01b0ng n&oacute; v\u1eabn c&oacute; th\u1ec3 \u0111\u01b0\u1ee3c b\u1ea3o m\u1eadt n\u1ebfu b\u1ea1n s\u1eed d\u1ee5ng n&oacute; h\u1ee3p l&yacute;. V\u1eady, h&atilde;y th\u1ef1c hi\u1ec7n theo nh\u1eefng \u0111i\u1ec1u n&ecirc;n v&agrave; kh&ocirc;ng n&ecirc;n sau \u0111&acirc;y \u0111\u1ec3 gi&uacute;p cho m\u1ea1ng kh&ocirc;ng d&acirc;y nh&agrave; b\u1ea1n \u0111\u01b0\u1ee3c an to&agrave;n h\u01a1n.<\/p>\n","protected":false},"author":6,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[129],"tags":[],"class_list":["post-940","post","type-post","status-publish","format-standard","hentry","category-thu-thuat-mang-web"],"views":425,"_links":{"self":[{"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/posts\/940","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/comments?post=940"}],"version-history":[{"count":0,"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/posts\/940\/revisions"}],"wp:attachment":[{"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/media?parent=940"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/categories?post=940"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/tapchicntt.com\/rest-api\/wp\/v2\/tags?post=940"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}