ECSE Departmental Research Seminars

Abstract:

Mobile IPv6 defines two modes of data communications between the mobile and correspondent nodes: i) indirect communications via the home agent using bidirectional tunneling established between the mobile node and home agent, referred as “bidirectional tunneling” and ii) direct communications between the mobile and correspondent nodes without routing through the home agent, called route optimization.

The bidirectional tunneling can be useful at a situation where the mobile node communicates with a node does not support Mobile IPv6 at all, allowing flexibility of integrating Mobile IPv6 with the existing Internet technologies. On the other hand, several problems are caused for using this mode. This communications mode makes the home agent to be a single point of failure. A long communication path is incurred as the data packets are routed via the home agent. Additional use of IPv6 header for tunneling can also increase the network load on the path between the mobile node and home agent. To solve these problems, communication path should be optimized to allow packets from the correspondent node to send directly to the current location of the mobile node.

For route optimization, packets from the correspondent node can be routed directly to the care-of address of the mobile node, or vise versa, to reduce the impact of any possible failure of the home agent or home networks. The mobile node is then bound to update the binding for the correspondent node when the mobile node attaches to a different link. While the correspondent registration is vulnerable to security threats, a successful completion of return routability procedure is required to authenticate the mobile node at its correspondent node. The trade-off for the use of route optimization is that the total delay on the data path is reduced, at the cost of registration latency.

However, original work on Mobile IPv6 communications assumes that the correspondent node is stationary. To the best of our knowledge, the workability and destination reachability in Mobile IPv6 have not yet been testified for mobile nodes communicating each other while roaming different subnets. So, we conduct research in the area of communications between two moving end hosts with Mobile IPv6. The main focus will be the enhancement of transmission efficiency for two devices roaming across different network domains. The approach aims to provide robust and lightweight protocols designed to make the most of constrained and hostile wireless environments.

This research consists of three components. First, we provide solutions to establish connectivity between two mobile devices while moving across different subnets. Then, we inspect the impact of signaling duration on packet loss in this scenario and present a novel approach to optimize mobility signaling communications with minimal changes to the current specification of Mobile IPv6. Last, we investigate data plane communications and seek for the enhancement. With the outputs of this research, delays mobility signaling and additional overhead of data packets could be reduced. Hence, improve the quality of network application services, particularly for those that are time-sensitive. This approach could have significant advantages for building future all-IP moving and mobile devices.