Hardware Based Packet Classification for High Speed Internet Routers

4.2 Multi-dimensional TCAM Minimization: The Optimization Techniques 37
Fig. 4.4 Example of lazing copying
and there is a one-to-one correspondence between the outgoing edges of v and the
outgoing edges of v ′ such that every pair of corresponding edges have identical
labels and they both point to the same node.
We next show an example where FDD reduction helps to reduce the number
of prex rules generated from an FDD. Consider the two equivalent FDDs in
where Figure 4.5a is non-reduced and Figure 4.5b is reduced. If we run our multidimensional
TCAM minimization algorithm on the two FDDs, we will produce 4
prex rules as shown in Table 4.5(a) and 2 prex rules as shown in Table 4.5(b),
respectively.
Fig. 4.5a Before FDD reduction
Fig. 4.5b After FDD reduction