diff --git a/tools/test/topos/chordal.py b/tools/test/topos/chordal.py
new file mode 100644
index 0000000..22f9ca1
--- /dev/null
+++ b/tools/test/topos/chordal.py
@@ -0,0 +1,402 @@
+"""
+"""
+from mininet.topo import Topo
+from mininet.net import Mininet
+from mininet.node import RemoteController
+from mininet.node import Node
+from mininet.node import CPULimitedHost
+from mininet.link import TCLink
+from mininet.cli import CLI
+from mininet.log import setLogLevel
+from mininet.util import dumpNodeConnections
+
+class chordalTopo( Topo ):
+
+    def __init__( self, **opts ):
+        "Create a topology."
+
+        # Initialize Topology
+        Topo.__init__( self, **opts )
+
+        # add nodes, switches first...
+        s1 = self.addSwitch( 's1' )
+        s2 = self.addSwitch( 's2' )
+        s3 = self.addSwitch( 's3' )
+        s4 = self.addSwitch( 's4' )
+        s5 = self.addSwitch( 's5' )
+        s6 = self.addSwitch( 's6' )
+        s7 = self.addSwitch( 's7' )
+        s8 = self.addSwitch( 's8' )
+        s9 = self.addSwitch( 's9' )
+        s10 = self.addSwitch( 's10' )
+        s11 = self.addSwitch( 's11' )
+        s12 = self.addSwitch( 's12' )
+        s13 = self.addSwitch( 's13' )
+        s14 = self.addSwitch( 's14' )
+        s15 = self.addSwitch( 's15' )
+        s16 = self.addSwitch( 's16' )
+        s17 = self.addSwitch( 's17' )
+        s18 = self.addSwitch( 's18' )
+        s19 = self.addSwitch( 's19' )
+        s20 = self.addSwitch( 's20' )
+        s21 = self.addSwitch( 's21' )
+        s22 = self.addSwitch( 's22' )
+        s23 = self.addSwitch( 's23' )
+        s24 = self.addSwitch( 's24' )
+        s25 = self.addSwitch( 's25' )
+
+        # ... and now hosts
+        s1_host = self.addHost( 'h1' )
+        s2_host = self.addHost( 'h2' )
+        s3_host = self.addHost( 'h3' )
+        s4_host = self.addHost( 'h4' )
+        s5_host = self.addHost( 'h5' )
+        s6_host = self.addHost( 'h6' )
+        s7_host = self.addHost( 'h7' )
+        s8_host = self.addHost( 'h8' )
+        s9_host = self.addHost( 'h9' )
+        s10_host = self.addHost( 'h10' )
+        s11_host = self.addHost( 'h11' )
+        s12_host = self.addHost( 'h12' )
+        s13_host = self.addHost( 'h13' )
+        s14_host = self.addHost( 'h14' )
+        s15_host = self.addHost( 'h15' )
+        s16_host = self.addHost( 'h16' )
+        s17_host = self.addHost( 'h17' )
+        s18_host = self.addHost( 'h18' )
+        s19_host = self.addHost( 'h19' )
+        s20_host = self.addHost( 'h20' )
+        s21_host = self.addHost( 'h21' )
+        s22_host = self.addHost( 'h22' )
+        s23_host = self.addHost( 'h23' )
+        s24_host = self.addHost( 'h24' )
+        s25_host = self.addHost( 'h25' )
+
+        # add edges between switch and corresponding host
+        self.addLink( s1 , s1_host )
+        self.addLink( s2 , s2_host )
+        self.addLink( s3 , s3_host )
+        self.addLink( s4 , s4_host )
+        self.addLink( s5 , s5_host )
+        self.addLink( s6 , s6_host )
+        self.addLink( s7 , s7_host )
+        self.addLink( s8 , s8_host )
+        self.addLink( s9 , s9_host )
+        self.addLink( s10 , s10_host )
+        self.addLink( s11 , s11_host )
+        self.addLink( s12 , s12_host )
+        self.addLink( s13 , s13_host )
+        self.addLink( s14 , s14_host )
+        self.addLink( s15 , s15_host )
+        self.addLink( s16 , s16_host )
+        self.addLink( s17 , s17_host )
+        self.addLink( s18 , s18_host )
+        self.addLink( s19 , s19_host )
+        self.addLink( s20 , s20_host )
+        self.addLink( s21 , s21_host )
+        self.addLink( s22 , s22_host )
+        self.addLink( s23 , s23_host )
+        self.addLink( s24 , s24_host )
+        self.addLink( s25 , s25_host )
+        self.addLink(s1, s2)
+        self.addLink(s1, s3)
+        self.addLink(s1, s4)
+        self.addLink(s1, s5)
+        self.addLink(s1, s6)
+        self.addLink(s1, s7)
+        self.addLink(s1, s8)
+        self.addLink(s1, s9)
+        self.addLink(s1, s10)
+        self.addLink(s1, s11)
+        self.addLink(s1, s12)
+        self.addLink(s1, s13)
+        self.addLink(s1, s14)
+        self.addLink(s1, s15)
+        self.addLink(s1, s16)
+        self.addLink(s1, s17)
+        self.addLink(s1, s18)
+        self.addLink(s1, s19)
+        self.addLink(s1, s20)
+        self.addLink(s1, s21)
+        self.addLink(s1, s22)
+        self.addLink(s1, s23)
+        self.addLink(s1, s24)
+        self.addLink(s1, s25)
+        self.addLink(s2, s3)
+        self.addLink(s2, s4)
+        self.addLink(s2, s5)
+        self.addLink(s2, s6)
+        self.addLink(s2, s7)
+        self.addLink(s2, s8)
+        self.addLink(s2, s9)
+        self.addLink(s2, s10)
+        self.addLink(s2, s11)
+        self.addLink(s2, s12)
+        self.addLink(s2, s13)
+        self.addLink(s2, s14)
+        self.addLink(s2, s15)
+        self.addLink(s2, s16)
+        self.addLink(s2, s17)
+        self.addLink(s2, s18)
+        self.addLink(s2, s19)
+        self.addLink(s2, s20)
+        self.addLink(s2, s21)
+        self.addLink(s2, s22)
+        self.addLink(s2, s23)
+        self.addLink(s2, s24)
+        self.addLink(s2, s25)
+        self.addLink(s3, s4)
+        self.addLink(s3, s5)
+        self.addLink(s3, s6)
+        self.addLink(s3, s7)
+        self.addLink(s3, s8)
+        self.addLink(s3, s9)
+        self.addLink(s3, s10)
+        self.addLink(s3, s11)
+        self.addLink(s3, s12)
+        self.addLink(s3, s13)
+        self.addLink(s3, s14)
+        self.addLink(s3, s15)
+        self.addLink(s3, s16)
+        self.addLink(s3, s17)
+        self.addLink(s3, s18)
+        self.addLink(s3, s19)
+        self.addLink(s3, s20)
+        self.addLink(s3, s21)
+        self.addLink(s3, s22)
+        self.addLink(s3, s23)
+        self.addLink(s3, s24)
+        self.addLink(s3, s25)
+        self.addLink(s4, s5)
+        self.addLink(s4, s6)
+        self.addLink(s4, s7)
+        self.addLink(s4, s8)
+        self.addLink(s4, s9)
+        self.addLink(s4, s10)
+        self.addLink(s4, s11)
+        self.addLink(s4, s12)
+        self.addLink(s4, s13)
+        self.addLink(s4, s14)
+        self.addLink(s4, s15)
+        self.addLink(s4, s16)
+        self.addLink(s4, s17)
+        self.addLink(s4, s18)
+        self.addLink(s4, s19)
+        self.addLink(s4, s20)
+        self.addLink(s4, s21)
+        self.addLink(s4, s22)
+        self.addLink(s4, s23)
+        self.addLink(s4, s24)
+        self.addLink(s4, s25)
+        self.addLink(s5, s6)
+        self.addLink(s5, s7)
+        self.addLink(s5, s8)
+        self.addLink(s5, s9)
+        self.addLink(s5, s10)
+        self.addLink(s5, s11)
+        self.addLink(s5, s12)
+        self.addLink(s5, s13)
+        self.addLink(s5, s14)
+        self.addLink(s5, s15)
+        self.addLink(s5, s16)
+        self.addLink(s5, s17)
+        self.addLink(s5, s18)
+        self.addLink(s5, s19)
+        self.addLink(s5, s20)
+        self.addLink(s5, s21)
+        self.addLink(s5, s22)
+        self.addLink(s5, s23)
+        self.addLink(s5, s24)
+        self.addLink(s5, s25)
+        self.addLink(s6, s7)
+        self.addLink(s6, s8)
+        self.addLink(s6, s9)
+        self.addLink(s6, s10)
+        self.addLink(s6, s11)
+        self.addLink(s6, s12)
+        self.addLink(s6, s13)
+        self.addLink(s6, s14)
+        self.addLink(s6, s15)
+        self.addLink(s6, s16)
+        self.addLink(s6, s17)
+        self.addLink(s6, s18)
+        self.addLink(s6, s19)
+        self.addLink(s6, s20)
+        self.addLink(s6, s21)
+        self.addLink(s6, s22)
+        self.addLink(s6, s23)
+        self.addLink(s6, s24)
+        self.addLink(s6, s25)
+        self.addLink(s7, s8)
+        self.addLink(s7, s9)
+        self.addLink(s7, s10)
+        self.addLink(s7, s11)
+        self.addLink(s7, s12)
+        self.addLink(s7, s13)
+        self.addLink(s7, s14)
+        self.addLink(s7, s15)
+        self.addLink(s7, s16)
+        self.addLink(s7, s17)
+        self.addLink(s7, s18)
+        self.addLink(s7, s19)
+        self.addLink(s7, s20)
+        self.addLink(s7, s21)
+        self.addLink(s7, s22)
+        self.addLink(s7, s23)
+        self.addLink(s7, s24)
+        self.addLink(s7, s25)
+        self.addLink(s8, s9)
+        self.addLink(s8, s10)
+        self.addLink(s8, s11)
+        self.addLink(s8, s12)
+        self.addLink(s8, s13)
+        self.addLink(s8, s14)
+        self.addLink(s8, s15)
+        self.addLink(s8, s16)
+        self.addLink(s8, s17)
+        self.addLink(s8, s18)
+        self.addLink(s8, s19)
+        self.addLink(s8, s20)
+        self.addLink(s8, s21)
+        self.addLink(s8, s22)
+        self.addLink(s8, s23)
+        self.addLink(s8, s24)
+        self.addLink(s8, s25)
+        self.addLink(s9, s10)
+        self.addLink(s9, s11)
+        self.addLink(s9, s12)
+        self.addLink(s9, s13)
+        self.addLink(s9, s14)
+        self.addLink(s9, s15)
+        self.addLink(s9, s16)
+        self.addLink(s9, s17)
+        self.addLink(s9, s18)
+        self.addLink(s9, s19)
+        self.addLink(s9, s20)
+        self.addLink(s9, s21)
+        self.addLink(s9, s22)
+        self.addLink(s9, s23)
+        self.addLink(s9, s24)
+        self.addLink(s9, s25)
+        self.addLink(s10, s11)
+        self.addLink(s10, s12)
+        self.addLink(s10, s13)
+        self.addLink(s10, s14)
+        self.addLink(s10, s15)
+        self.addLink(s10, s16)
+        self.addLink(s10, s17)
+        self.addLink(s10, s18)
+        self.addLink(s10, s19)
+        self.addLink(s10, s20)
+        self.addLink(s10, s21)
+        self.addLink(s10, s22)
+        self.addLink(s10, s23)
+        self.addLink(s10, s24)
+        self.addLink(s10, s25)
+        self.addLink(s11, s12)
+        self.addLink(s11, s13)
+        self.addLink(s11, s14)
+        self.addLink(s11, s15)
+        self.addLink(s11, s16)
+        self.addLink(s11, s17)
+        self.addLink(s11, s18)
+        self.addLink(s11, s19)
+        self.addLink(s11, s20)
+        self.addLink(s11, s21)
+        self.addLink(s11, s22)
+        self.addLink(s11, s23)
+        self.addLink(s11, s24)
+        self.addLink(s11, s25)
+        self.addLink(s12, s13)
+        self.addLink(s12, s14)
+        self.addLink(s12, s15)
+        self.addLink(s12, s16)
+        self.addLink(s12, s17)
+        self.addLink(s12, s18)
+        self.addLink(s12, s19)
+        self.addLink(s12, s20)
+        self.addLink(s12, s21)
+        self.addLink(s12, s22)
+        self.addLink(s12, s23)
+        self.addLink(s12, s24)
+        self.addLink(s12, s25)
+        self.addLink(s13, s14)
+        self.addLink(s13, s15)
+        self.addLink(s13, s16)
+        self.addLink(s13, s17)
+        self.addLink(s13, s18)
+        self.addLink(s13, s19)
+        self.addLink(s13, s20)
+        self.addLink(s13, s21)
+        self.addLink(s13, s22)
+        self.addLink(s13, s23)
+        self.addLink(s13, s24)
+        self.addLink(s13, s25)
+        self.addLink(s14, s15)
+        self.addLink(s14, s16)
+        self.addLink(s14, s17)
+        self.addLink(s14, s18)
+        self.addLink(s14, s19)
+        self.addLink(s14, s20)
+        self.addLink(s14, s21)
+        self.addLink(s14, s22)
+        self.addLink(s14, s23)
+        self.addLink(s14, s24)
+        self.addLink(s14, s25)
+        self.addLink(s15, s16)
+        self.addLink(s15, s17)
+        self.addLink(s15, s18)
+        self.addLink(s15, s19)
+        self.addLink(s15, s20)
+        self.addLink(s15, s21)
+        self.addLink(s15, s22)
+        self.addLink(s15, s23)
+        self.addLink(s15, s24)
+        self.addLink(s15, s25)
+        self.addLink(s16, s17)
+        self.addLink(s16, s18)
+        self.addLink(s16, s19)
+        self.addLink(s16, s20)
+        self.addLink(s16, s21)
+        self.addLink(s16, s22)
+        self.addLink(s16, s23)
+        self.addLink(s16, s24)
+        self.addLink(s16, s25)
+        self.addLink(s17, s18)
+        self.addLink(s17, s19)
+        self.addLink(s17, s20)
+        self.addLink(s17, s21)
+        self.addLink(s17, s22)
+        self.addLink(s17, s23)
+        self.addLink(s17, s24)
+        self.addLink(s17, s25)
+        self.addLink(s18, s19)
+        self.addLink(s18, s20)
+        self.addLink(s18, s21)
+        self.addLink(s18, s22)
+        self.addLink(s18, s23)
+        self.addLink(s18, s24)
+        self.addLink(s18, s25)
+        self.addLink(s19, s20)
+        self.addLink(s19, s21)
+        self.addLink(s19, s22)
+        self.addLink(s19, s23)
+        self.addLink(s19, s24)
+        self.addLink(s19, s25)
+        self.addLink(s20, s21)
+        self.addLink(s20, s22)
+        self.addLink(s20, s23)
+        self.addLink(s20, s24)
+        self.addLink(s20, s25)
+        self.addLink(s21, s22)
+        self.addLink(s21, s23)
+        self.addLink(s21, s24)
+        self.addLink(s21, s25)
+        self.addLink(s22, s23)
+        self.addLink(s22, s24)
+        self.addLink(s22, s25)
+        self.addLink(s23, s24)
+        self.addLink(s23, s25)
+        self.addLink(s24, s25)
+
+topos = { 'chordal': ( lambda: chordalTopo() ) }