摘要 |
An Internet Protocol address look-up method for looking up an Internet Protocol address of an Internet Protocol packet in order to forward the Internet Protocol packet uses a ternary content addressable memory (CAM) which has routing entries, each including a pair of data strings having a prefix of an Internet Protocol address and a mask string representing a length of the prefix, which compares a search key as a destination address of the Internet Protocol packet to be forwarded with the routing entries, which sets a match line of a matching routing entry, and which outputs a mask string of the matching routing entry. The method comprises the steps of: comparing prefix lengths of mask strings outputted in correspondence to set match lines when at least one match line is set in the ternary content addressable memory (CAM); and determining, as a longest prefix matching (LPM) entry, a routing entry corresponding to a mask string having the longest prefix length.
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