When documenting your network infrastructure, you are obtaining both hardware data to document your infrastructure's physical structure and software data to document the existence and configuration of the protocols in use on your network.
1. perpendicular-a straight line at right angles to another line. straight line-a line traced by a point traveling in a constant direction; a line of zero curvature; the shortest distance between two points is a straight line.
Those crafty little weasels. If two lines are perpendicular to the same line, we know that they're parallel. If we take another look at the perpendicular lines, we'll see that we have four sets of parallel lines here as well: a || d, b || g, c || f, and e || h. Seeing these relationships among segments and angles makes it possible to find angle measures and side lengths in polygons.