Over-the-air management of multi-mode mobile hosts using SNMP

IEEE 802.11 WLANs (wireless LAN) are proliferating at an unprecedented rate. To realize the benefits of localized, high-bandwidth WLANs along with highly available, low bit-rate overlay WWANs (wireless WAN), mobile hosts (MH), such as laptops and PDAs, are being equipped with multiple wireless network interface cards (NIC). This enables a mobile user to switch to a WLAN, if available, and then switch back to the overlay WWAN upon moving out of WLAN coverage. Consequently, also growing strongly is the desire to develop a capability to monitor, trouble-shoot and manage these complex devices over-the-air. However, a key requirement for an effective MH management system is not only to undertake the conventional device management tasks but also have the ability to track MHs switching between WLAN and WWAN networks. We present a novel MH management scheme that uses SNMP (simple network management protocol) to address the requirements. An SNMP agent is installed on each MH along with an appropriate MIB (management information base). The mobiles are then managed by a centralized SNMP manager. The mobility within the WWAN is left to the native mobility management procedures of the WWAN whereas the mode-switching between WWAN and WLAN is notified to the SNMP manager through SNMP traps. The proposed scheme is a simple yet effective solution to compliment the conventional MH management functionality with the ability to support mobility management in a multi-mode wireless overlay environment, without imposing unnecessary overheads such as mobile IP, external proxies or alterations to the protocol stacks.