diff --git a/bin/rrd-extractstats.pl b/bin/rrd-extractstats.pl
index 4cf278f..f134269 100755
--- a/bin/rrd-extractstats.pl
+++ b/bin/rrd-extractstats.pl
@@ -30,7 +30,7 @@ read_knownlinks();
 my @links = values %knownlinks;
 
 # walk through all RRD files in the given path and extract stats for all links
-# from them; write the stats to a text file, sorted by total traffic
+# from them; write the stats to an sqlite database
 
 my @rrdfiles = File::Find::Rule->maxdepth(2)->file->in($rrdpath);
 
@@ -51,45 +51,34 @@ foreach my $rrdfile (@rrdfiles) {
 }
 print "\n";
 
-# now sort the keys in order of descending total traffic
-my @asorder = sort {
-	my $total_a = 0;
-	
-	foreach my $t (values %{$astraffic->{$a}}) {
-		$total_a += $t;
-	}
-	my $total_b = 0;
-	foreach my $t (values %{$astraffic->{$b}}) {
-		$total_b += $t;
-	}
-	return $total_b <=> $total_a;
-} keys %$astraffic;
-
-open(STATSFILE, ">$statsfile.tmp");
-
-# print header line
-print STATSFILE "as";
+my $query = 'create table stats(asn int';
 foreach my $link (@links) {
-	print STATSFILE "\t${link}_in\t${link}_out\t${link}_v6_in\t${link}_v6_out";
+	$query .= ", ${link}_in int, ${link}_out int, ${link}_v6_in int, ${link}_v6_out int";
 }
-print STATSFILE "\n";
+$query .= ');';
+
+use DBI;
+my $db = DBI->connect("dbi:SQLite:dbname=$statsfile.tmp", '', '');
+$db->do('PRAGMA synchronous = OFF');
+$db->do('drop table if exists stats');
+$db->do($query);
 
 # print data
-foreach my $as (@asorder) {
-	print STATSFILE "$as";
+foreach my $as (keys %{ $astraffic }) {
+
+	$query = "insert into stats values('$as'";
 	
 	foreach my $link (@links) {
-		print STATSFILE "\t" . undefaszero($astraffic->{$as}->{"${link}_in"});
-		print STATSFILE "\t" . undefaszero($astraffic->{$as}->{"${link}_out"});
-		print STATSFILE "\t" . undefaszero($astraffic->{$as}->{"${link}_v6_in"});
-		print STATSFILE "\t" . undefaszero($astraffic->{$as}->{"${link}_v6_out"});
+		$query .= ", '" . undefaszero($astraffic->{$as}->{"${link}_in"}) . "'";
+		$query .= ", '" . undefaszero($astraffic->{$as}->{"${link}_out"}) . "'";
+		$query .= ", '" . undefaszero($astraffic->{$as}->{"${link}_v6_in"}) . "'";
+		$query .= ", '" . undefaszero($astraffic->{$as}->{"${link}_v6_out"}) . "'";
 	}
-	
-	print STATSFILE "\n";
+	$query .= ');';
+	$db->do($query);
 }
 
-close(STATSFILE);
-
+$db->disconnect();
 rename("$statsfile.tmp", $statsfile);
 
 sub undefaszero {
diff --git a/www/config.inc b/www/config.inc
index 4889397..ecb423d 100644
--- a/www/config.inc
+++ b/www/config.inc
@@ -17,7 +17,6 @@ $show95th = true;
 $ntop = 20;
 $showv6 = true;
 $showtitledetail = true;
-$hidelinkusagename = true;	  	# $showtitledetail will need to be true to allow this
 $vertical_label = true;			# vertical IN/OUT label in graph
 $brighten_negative = true;		# brighten the "negative" part of graphs
 
diff --git a/www/config_defaults.inc b/www/config_defaults.inc
index 26c6919..835faa7 100644
--- a/www/config_defaults.inc
+++ b/www/config_defaults.inc
@@ -10,10 +10,6 @@ $default_graph_height = 360;
 $top_graph_width = 600;
 $top_graph_height = 220;
 
-/* Size of graphs on link usage page */
-$linkusage_graph_width = 600;
-$linkusage_graph_height = 480;
-
 /* Size of graphs on AS-Set page */
 $asset_graph_width = 600;
 $asset_graph_height = 200;
diff --git a/www/func.inc b/www/func.inc
index b7890bf..4cbcd93 100644
--- a/www/func.inc
+++ b/www/func.inc
@@ -95,49 +95,52 @@ function getknownlinks() {
 	return $knownlinks;
 }
 
-function getasstats_top($ntop, $statfile) {	
-	/* first step: walk the data for all ASes to determine the top 5 for the given link */
-	$fd = fopen($statfile, "r");
-	if (!$fd)
+function getasstats_top($ntop, $statfile, $selected_links) {
+	try{
+		$db = new SQLite3($statfile);
+	}catch(Exception $e){
 		return array();
-	$cols = explode("\t", trim(fgets($fd)));
-	
-	/* read in up to $ntop AS stats, sum up columns */
-	while (!feof($fd)) {
-		$line = trim(fgets($fd));
-		if (!$line)
-			continue;
-		
-		$els = explode("\t", $line);
-		
-		/* first element is the AS */
-		$as = $els[0];
+	}
+
+	if(sizeof($selected_links) == 0){
+		$selected_links = array();
+		foreach(getknownlinks() as $link)
+			$selected_links[] = $link['tag'];
+	}
+
+	$nlinks = 0;
+	$query_total = '0';
+	$query_links = '';
+	foreach($selected_links as $tag){
+		$query_links .= "${tag}_in, ${tag}_out, ${tag}_v6_in, ${tag}_v6_out, ";
+		$nlinks += 4;
+		$query_total .= " + ${tag}_in + ${tag}_out + ${tag}_v6_in + ${tag}_v6_out";
+	}
+	$query = "select asn, $query_links $query_total as total from stats order by total desc limit $ntop";
+
+	$asn = $db->query($query);
+	$asstats = array();
+	while($row = $asn->fetchArray()){
 		$tot_in = 0;
 		$tot_out = 0;
 		$tot_v6_in = 0;
 		$tot_v6_out = 0;
-		
-		for ($i = 1; $i < count($els); $i++) {
-			if (strpos($cols[$i], "_in") !== false) {
-				if (strpos($cols[$i], "_v6_") !== false)
-					$tot_v6_in += $els[$i];
+		foreach($row as $key => $value){
+			if (strpos($key, '_in') !== false) {
+				if (strpos($key, '_v6_') !== false)
+					$tot_v6_in += $value;
 				else
-					$tot_in += $els[$i];
-			} else {
-				if (strpos($cols[$i], "_v6_") !== false)
-					$tot_v6_out += $els[$i];
+					$tot_in += $value;
+			} else if (strpos($key, '_out') !== false) {
+				if (strpos($key, '_v6_') !== false)
+					$tot_v6_out += $value;
 				else
-					$tot_out += $els[$i];
+					$tot_out += $value;
 			}
 		}
-		
-		$asstats[$as] = array($tot_in, $tot_out, $tot_v6_in, $tot_v6_out);
-		
-		if (count($asstats) >= $ntop)
-			break;
+
+		$asstats[$row['asn']] = array($tot_in, $tot_out, $tot_v6_in, $tot_v6_out);
 	}
-	fclose($fd);
-	
 	return $asstats;
 }
 
@@ -224,14 +227,14 @@ function clearCacheFileASSET($asset) {
 }
 
 # return the html used in top.php : <a href=blabla><img src=blabla/></url>
-function getHTMLUrl($as, $ipversion, $desc, $start, $end, $peerusage){
-	$img = getHTMLImg($as, $ipversion, $desc, $start, $end, $peerusage, '', '', false);
+function getHTMLUrl($as, $ipversion, $desc, $start, $end, $peerusage, $selected_links = array()){
+	$img = getHTMLImg($as, $ipversion, $desc, $start, $end, $peerusage, '', '', false, $selected_links);
 	$result = "<a href='history.php?as=$as&peerusage=$peerusage&v=$ipversion' target='_blank'>$img</a>";
 	return($result);
 }
 
 # return the html used in history.php (for example) : <img src=blabla/>
-function getHTMLImg($as, $ipversion, $desc, $start, $end, $peerusage, $alt, $class, $history = false){
+function getHTMLImg($as, $ipversion, $desc, $start, $end, $peerusage, $alt, $class, $history = false, $selected_links=array()){
 	global $top_graph_width;
 	global $top_graph_height;
 
@@ -240,6 +243,14 @@ function getHTMLImg($as, $ipversion, $desc, $start, $end, $peerusage, $alt, $cla
 	$result = "<img alt='$alt' class='$class' src='gengraph.php?v=$ipversion&as=$as&peerusage=$peerusage&dname=$dname&start=$start&end=$end";
 	if(!$history)
 		$result .= "&width=$top_graph_width&height=$top_graph_height&nolegend=1";
+
+	if(sizeof($selected_links) != 0){
+		$result .= "&selected_links=";
+		foreach($selected_links as $link)
+			$result .= "$link,";
+		$result = rtrim($result, ',');
+	}
+
 	$result .= "'";
 
 	if(!$history)
diff --git a/www/gengraph.php b/www/gengraph.php
index 71803b7..a2d7f68 100644
--- a/www/gengraph.php
+++ b/www/gengraph.php
@@ -29,6 +29,23 @@ else
 	$peerusage = 0;
 
 $knownlinks = getknownlinks();
+
+if(isset($_GET['selected_links'])){
+	$reverse = array();
+	foreach($knownlinks as $link)
+		$reverse[$link['tag']] = array('color' => $link['color'], 'descr' => $link['descr']);
+
+	$links = array();
+	foreach(explode(',', $_GET['selected_links']) as $tag){
+		$link = array('tag' => $tag,
+				'color' => $reverse[$tag]['color'],
+				'descr' => $reverse[$tag]['descr']);
+		$links[] = $link;
+	}
+
+	$knownlinks = $links;
+}
+
 $rrdfile = getRRDFileForAS($as, $peerusage);
 
 if ($compat_rrdtool12) {
diff --git a/www/headermenu.inc b/www/headermenu.inc
index 0cebc10..58cd040 100644
--- a/www/headermenu.inc
+++ b/www/headermenu.inc
@@ -17,14 +17,6 @@ if($showpeeras == true){
 	endif;
 }
 
-echo "<span>Link usage:</span> ";
-foreach ($top_intervals as $interval) {
-	echo '<a href="linkusage.php?numhours=' . $interval['hours'] . '"';
-	if ($dpagename == "linkusage" && @$_GET['numhours'] == $interval['hours'])
-		echo ' class="selected"';
-	echo '>' . $interval['label'] . '</a> | ';
-}
-
 if ($dpagename == "history"): 
 	?><a href="history.php" class="selected">View an AS</a> | <?php
 else:
diff --git a/www/top.php b/www/top.php
index cd702ef..9269495 100644
--- a/www/top.php
+++ b/www/top.php
@@ -25,7 +25,15 @@ else {
 	$statsfile = statsFileForHours($hours);
 }
 $label = statsLabelForHours($hours);
-$topas = getasstats_top($ntop, $statsfile);
+
+$knownlinks = getknownlinks();
+$selected_links = array();
+foreach($knownlinks as $link){
+	if(isset($_GET["link_${link['tag']}"]))
+		$selected_links[] = $link['tag'];
+}
+
+$topas = getasstats_top($ntop, $statsfile, $selected_links);
 
 $start = time() - $hours*3600;
 $end = time();
@@ -98,9 +106,9 @@ echo join(" | ", $htmllinks);
 	</th>
 	<td>
 		<?php
-		echo getHTMLUrl($as, 4, $asinfo['descr'], $start, $end, $peerusage);
+		echo getHTMLUrl($as, 4, $asinfo['descr'], $start, $end, $peerusage, $selected_links);
 		if ($showv6)
-			echo getHTMLUrl($as, 6, $asinfo['descr'], $start, $end, $peerusage);
+			echo getHTMLUrl($as, 6, $asinfo['descr'], $start, $end, $peerusage, $selected_links);
 		?>
 	</td>
 </tr>
@@ -109,11 +117,20 @@ echo join(" | ", $htmllinks);
 </table>
 
 <div id="legend">
+<form method='get'>
+<input type='hidden' name='numhours' value='<?php echo $hours; ?>'/>
+<input type='hidden' name='n' value='<?php echo $ntop; ?>'/>
 <table>
 <?php
 $knownlinks = getknownlinks();
 foreach ($knownlinks as $link) {
-	echo "<tr><td style=\"border: 4px solid #fff;\">";
+	$tag = "link_${link['tag']}";
+
+	echo "<tr><td><input type='checkbox'";
+	if(isset($_GET[$tag]) && $_GET[$tag] == 'on')
+		echo " checked='checked'";
+
+	echo "name=\"$tag\" id=\"$tag\"/></td><td style=\"border: 4px solid #fff;\">";
 	
 	echo "<table style=\"border-collapse: collapse; margin: 0; padding: 0\"><tr>";
         if ($brighten_negative) {
@@ -124,10 +141,12 @@ foreach ($knownlinks as $link) {
 	}
 	echo "</tr></table>";
 	
-	echo "</td><td>&nbsp;" . $link['descr'] . "</td></tr>\n";
+	echo "</td><td><label for=\"$tag\">&nbsp;${link['descr']}</label></td></tr>\n";
 }
 ?>
 </table>
+<center><input type='submit' value='Filter'/></center>
+</form>
 </div>
 
 <?php include('footer.inc'); ?>