+sub is_node
+{
+ my $self = shift;
+ return $self->{sort} =~ /[ACRSX]/;
+}
+
+sub is_user
+{
+ my $self = shift;
+ return $self->{sort} eq 'U';
+}
+
+sub is_bbs
+{
+ my $self = shift;
+ return $self->{sort} eq 'B';
+}
+
+sub is_spider
+{
+ my $self = shift;
+ return $self->{sort} eq 'S';
+}
+
+sub is_clx
+{
+ my $self = shift;
+ return $self->{sort} eq 'C';
+}
+
+sub is_dxnet
+{
+ my $self = shift;
+ return $self->{sort} eq 'X';
+}
+
+sub is_arcluster
+{
+ my $self = shift;
+ return $self->{sort} eq 'R';
+}
+
+sub is_ak1a
+{
+ my $self = shift;
+ return $self->{sort} eq 'A';
+}