     for l in data.links
       left = @nodes_map[l.left]
       right = @nodes_map[l.right]
-      @links.push new Link(left, right)
+      @links.push new Link(left, right) if left && right
 
     @svg = d3.select('#topology')
       .append('svg')

        classes: "ui-tooltip-tipsy"

  rescale: =>
    console.log "Rescaling"
    trans = d3.event.translate
    scale = d3.event.scale
    @svg.attr("transform", "translate(#{trans}) scale(#{scale})")

    @nodes_map = {}
    for d in data.converters
      i = new Node(d)
      continue if i.bad_node()
      @nodes.push i
      @nodes_map[i.key] = i

