An LPM prefix is represented by a pair of parameters (128-bit key, depth), with depth in the range of 1 to 128.
An LPM rule is represented by an LPM prefix and some user data associated with the prefix.
The prefix serves as the unique identifier for the LPM rule.
-In this implementation, the user data is 1-byte long and is called "next hop",
+In this implementation, the user data is 21-bits long and is called "next hop",
which corresponds to its main use of storing the ID of the next hop in a routing table entry.
The main methods exported for the LPM component are: