"); background-position: 50% 31px; text-align:center; font:x-small Verdana, Arial, Sans-serif; color:#aabbcc; font-size/* */:/**/small; font-size: /**/small; } /* Page Structure ----------------------------------------------- */ */ body { background- url(""); background-attachment: fixed; background-repeat: repeat; } ") no-repeat 250px 50px; width:700px; margin:0 auto; text-align:left; font:normal normal 100% Verdana,Arial,Sans-Serif; } #header-wrapper { display: none; } #main-wrapper { width:450px; float:right; padding:100px 0 20px; font-size:85%; word-wrap: break-word; /* fix for long text breaking sidebar float in IE */ overflow: hidden; /* fix for long non-text content breaking IE sidebar float */ } #main { background:url("http:// ") -100px -100px; padding:20px 10px 15px; } #sidebar-wrapper { width:200px; float:left; font-size:85%; padding-bottom:20px; word-wrap: break-word; /* fix for long text breaking sidebar float in IE */ overflow: hidden; /* fix for long non-text content breaking IE sidebar float */ } #sidebar { background:url("") 150px -50px; padding:40px 10px 15px; width:200px; width/* */:/**/180px; width: /**/180px; } /* Title & Description ----------------------------------------------- */ .Header h1 { margin:0 0 .5em; line-height: 1.4em; font: normal bold 250% Helvetica,Arial,Sans-serif; color: #88dddd; } .Header h1 a { color:#88dddd; text-decoration:none; } .Header .description { margin:0 0 1.75em; color: #99cc77; font: normal normal 100% Helvetica, Arial, Sans-serif; } /* Links ----------------------------------------------- */ a:link { color:#ddaa77; } a:visited { color:#779999; } a:hover { color:#779999; } a img { border-width:0; } /* Posts ----------------------------------------------- */ h2.date-header { margin:0 0 .75em; padding-bottom:.35em; border-bottom:1px dotted #556677; text-transform: lowercase; letter-spacing:.3em; color: #77bbcc; font: normal bold 100% Verdana, Sans-serif; } .post { margin:0 0 2.5em; } .post h3 { margin:.25em 0; line-height: 1.4em; font: normal bold 95% Verdana,Sans-serif; font-size: 130%; 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margin-left:0; padding:4px; border:1px solid #556677; } .feed-links { clear: both; line-height: 2.5em; } #blog-pager-newer-link { float: left; } #blog-pager-older-link { float: right; } #blog-pager { text-align: center; } /* Comments ----------------------------------------------- */ #comments { margin:0; } #comments h4 { margin:0 0 10px; border-top:1px dotted #556677; padding-top:.5em; line-height: 1.4em; font: bold 110% Georgia,Serif; color:#9c7; } #comments-block { line-height:1.6em; } .comment-author { background:url("") no-repeat 2px .35em; margin:.5em 0 0; padding-top:0; padding-right:0; padding-bottom:0; padding-left:20px; font-weight:bold; } .comment-body { margin:0; padding-top:0; padding-right:0; padding-bottom:0; padding-left:20px; } .comment-body p { margin:0 0 .5em; } .comment-footer { margin:0 0 .5em; padding-top:0; padding-right:0; padding-bottom:.75em; padding-left:20px; color:#996; } .comment-footer a:link { color:#996; } .deleted-comment { font-style:italic; color:gray; } /* More Sidebar Content ----------------------------------------------- */ .sidebar h2 { margin:2em 0 .75em; padding-bottom:.35em; border-bottom:1px dotted #556677; line-height: 1.4em; font: normal bold 95% Verdana,Sans-serif; text-transform:lowercase; color:#77bbcc; } .sidebar p { margin:0 0 .75em; line-height:1.6em; } .sidebar ul { list-style:none; margin:.5em 0; padding:0 0px; } .sidebar .widget { margin: .5em 0 1em; padding: 0 0px; line-height: 1.5em; } .main .widget { padding-bottom: 1em; } .sidebar ul li { background:url("") no-repeat 3px .45em; margin:0; padding-top:0; padding-right:0; padding-bottom:5px; padding-left:15px; } .sidebar p { margin:0 0 .6em; } /* Profile ----------------------------------------------- */ .profile-datablock { margin: 0 0 1em; } .profile-img { float: left; margin-top: 0; margin-right: 8px; margin-bottom: 5px; margin-left: 0; border: 4px solid #345; } .profile-data { margin: 0; line-height: 1.5em; } .profile-textblock { clear: left; margin-left: 0; } /* Footer ----------------------------------------------- */ #footer { clear:both; padding:15px 0 0; } #footer p { margin:0; } /* Page structure tweaks for layout editor wireframe */ body#layout #sidebar, body#layout #main, body#layout #main-wrapper, body#layout #outer-wrapper, body#layout #sidebar-wrapper { padding: 0; } body#layout #sidebar-wrapper, body#layout #sidebar { padding: 0; width: 240px; } -->

Monday, September 15, 2008

Layer 2: Data Link Layer
The Data Link Layer provides the functional and procedural means to transfer data between network entities and to detect and possibly correct errors that may occur in the Physical Layer. Originally, this layer was intended for point-to-point and point-to-multipoint media, characteristic of wide area media in the telephone system.
The best example of data link is the LAN and WAN....

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