The network address translation problem of the home automation network: issues and solutions

The home automation network (HAN) has become an important research topic for the past few years. Standards and technologies for HAN have been proposed and are frequently discussed in both academic and industrial circles. The residential gateway (RG) is the cross connect device that handles all external accesses to HAN. The RG has to provide the network address translation (NAT) mechanism for solving the addressing problem, since the IPv4 addressing scheme is inadequate for today´s Internet; i.e., it is impossible to assign a unique IP address to every in-home device. All IP-sensitive applications on RG can cause security problems while using the NAT router. The Realm Specific IP (RSIP) provides an alternative to remedy this limitation, but complications still exist. In this paper, we propose solutions to these complications by using the lightweight directory access protocol (LDAP). We define a LDAP schema that can be used to store all necessary information generated by RSIP. The RSIP in conjunction with the LDAP schema provides a robust mechanism for dealing with the network address translation problem of HAN.