Here is a quick hack I put together (I assumed that you only have NAME, ID, and TIME as fields).

my $time = 50;
while (<IN>){
@tmp_split = split /:/,$_;
# Print the previous entry if valid
print OUT "NAME:$tmp_hash{\"NAME\"}ID:$tmp_hash{\"ID\"}TIME:$tmp_hash{
+\"TIME\"}" if ($tmp_split[0] eq "NAME" && $tmp_hash{"TIME"} > $time);
# Put the values in a hash for storage
$tmp_hash{$tmp_split[0]}=$tmp_split[1];
}
# Print the last entry if valid
print OUT "NAME:$tmp_hash{\"NAME\"}ID:$tmp_hash{\"ID\"}TIME:$tmp_hash{
+\"TIME\"}" if ($tmp_hash{"TIME"} > $time);
[download]

I hope that helps.