diff --git a/Info/Bridge.pm b/Info/Bridge.pm
index 0663ebdb..86eb5232 100644
--- a/Info/Bridge.pm
+++ b/Info/Bridge.pm
@@ -308,6 +308,8 @@ sub i_vlan {
     return $i_vlan;
 }
 
+sub i_untagged { goto &i_vlan }
+
 sub i_vlan_membership {
     my $bridge  = shift;
     my $partial = shift;
@@ -365,6 +367,8 @@ sub set_i_vlan {
     return;
 }
 
+sub set_i_untagged { goto &set_i_vlan }
+
 sub set_add_i_vlan_tagged {
     my $bridge = shift;
 
@@ -597,6 +601,10 @@ to a hash.
 
 Returns a mapping between C<ifIndex> and the PVID or default VLAN.
 
+=item $vtp->i_untagged()
+
+An alias for C<i_vlan>.
+
 =item $bridge->i_vlan_membership()
 
 Returns reference to hash of arrays: key = C<ifIndex>, value = array of VLAN
@@ -893,6 +901,10 @@ operations.
 
 Currently unsupported.  Throws an error and returns.
 
+=item $bridge->set_i_untagged(vlan, ifIndex)
+
+An alias for C<set_i_vlan>.
+
 =item $bridge->set_i_pvid(pvid, ifIndex)
 
 Currently unsupported.  Throws an error and returns.
diff --git a/Info/CiscoVTP.pm b/Info/CiscoVTP.pm
index 93525cee..a22bf401 100644
--- a/Info/CiscoVTP.pm
+++ b/Info/CiscoVTP.pm
@@ -143,9 +143,6 @@ sub v_index {
     return \%v_index;
 }
 
-sub i_pvid { goto &i_vlan }
-sub i_untagged { goto &i_vlan }
-
 sub i_vlan {
     my $vtp     = shift;
     my $partial = shift;
@@ -194,6 +191,22 @@ sub i_vlan {
     return \%i_vlans;
 }
 
+sub i_untagged {
+    my $vtp = shift;
+    my ( $ifindex ) = @_;
+
+    # cannot defer to i_vlan - vtp_trunk_dyn_stat is not useful for down ports
+    # so we use vtp_trunk_dyn as a hint to use i_pvid
+
+    my $trunking = eval { $vtp->vtp_trunk_dyn($ifindex)->{$ifindex} };
+    if ($trunking and (($trunking eq 'on') or ($trunking eq 'onNoNegotiate'))) {
+        return $vtp->i_pvid(@_);
+    }
+    else {
+        return $vtp->i_vlan(@_);
+    }
+}
+
 sub i_vlan_membership {
     my $vtp     = shift;
     my $partial = shift;
@@ -313,6 +326,9 @@ sub set_i_untagged {
     my $vtp = shift;
     my ( $vlan_id, $ifindex ) = @_;
 
+    # cannot defer to i_vlan - vtp_trunk_dyn_stat is not useful for down ports
+    # so we use vtp_trunk_dyn as a hint to use i_pvid
+
     my $trunking = eval { $vtp->vtp_trunk_dyn($ifindex)->{$ifindex} };
     if ($trunking and (($trunking eq 'on') or ($trunking eq 'onNoNegotiate'))) {
         return $vtp->set_i_pvid(@_);
@@ -556,10 +572,6 @@ Your device will only implement a subset of these methods.
 Returns a mapping between C<ifIndex> and assigned VLAN ID for access ports
 and the default VLAN ID for trunk ports.
 
-=item $vtp->i_pvid()
-
-An alias for C<i_vlan>.
-
 =item $vtp->i_untagged()
 
 An alias for C<i_vlan>.