The Need for Address Translation

Call from Private Network to PDN

For private networks that impose a particular addressing scheme, address translation is needed to convert the private scheme into the public address format.

Address translation can be used to make the connection to the PDN transparent to the users. In the example below, User A would enter a 5-digit address to reach Destination B, even though B's real address has 14 digits.

We first will have to remove the first 9 of the Called addresses. This first 9 is sometime used to route the call to a output port that is connected the the PDN. We must now get ride of it.

Next is to add the correct prefix to the remain four digits. We could do this operation by a look up table and when we see 9134 we will add a prefix of 3110412442 to the remaining digits

This should complete the operation, and now the correct address is being sent to the PDN so they can route the call correctly to its destination.