Message delivery in heterogeneous networks prone to episodic connectivity

Abstract

We present an efficient message delivery framework, called MeDeHa, which enables communication in an internet connecting heterogeneous networks that is prone to disruptions in connectivity. MeDeHa is complementary to the IRTF's Bundle Architecture: besides its ability to store messages for unavailable destinations, MeDeHa can bridge the connectivity gap between infrastructure-based and multi-hop infrastructure-less networks. It benefits from network heterogeneity (e.g., nodes supporting more than one network and nodes having diverse resources) to improve message delivery. For example, in IEEE 802.11 networks, participating nodes may use both infrastructure-and ad-hoc modes to deliver data to otherwise unavailable destinations. It also employs opportunistic routing to support nodes with episodic connectivity. One of MeDeHa's key features is that any MeDeHa node can relay data to any destination and can act as a gateway to make two networks inter-operate or to connect to the backbone network. The network is able to store data destined to temporarily unavailable nodes till the time of their expiry. This time period depends upon current storage availability as well as quality-of-service needs (e.g., delivery delay bounds) imposed by the application. We showcase MeDeHa's ability to operate in environments consisting of a diverse set of interconnected networks and evaluate its performance through extensive simulations using a variety of scenarios with realistic synthetic and real mobility traces. Our results show significant improvement in average delivery ratio and a significant decrease in average delivery delay in the face of episodic connectivity. We also demonstrate that MeDeHa supports different levels of qualityof-service through traffic differentiation and message prioritization.

Naming for heterogeneous networks prone to episodic connectivity

“…Campus 1 and 2 has an area of 600m x 600m, while Campus 3 spans over an area of 600m x 300m, and the total simulation area is 3km x 1.5km. For opportunistic ad-hoc forwarding in MeDeHa, we use Encounter-based Replication mechanism (ER) as described in [12], where a source or a relay forwards a message to another relay, if the latter has encountered the destination at least twice and more often than the former. As both Bob and Alice change their IP address with the change in the network attachment point, it is interesting what percentage of the file they receive in each network that they visit.…”

“…A MDH node sends the LOC UPDATE to its LMS, when it is associated to an ISbased node (e.g., an AP or base station), or when it is indirectly connected via a neighboring node associated to an IS network. Besides, the MeDeHa notification protocol [12] has been extended so that APs exchange GUIDs of the associated MDH nodes instead of IP addresses in IS network, and in ad-hoc mode, MDH nodes exchange both their GUID and IP address in neighbor sensing handshake (comprising of HELLO and NEIGHBOR INFO). Besides, nodes also exchange GUID of the nodes that they encountered in the past.…”

“…HeNNA is designed to be used with the current Internet routing, while accommodating node mobility, address changes, as well as temporary or long-lived disconnections. We implement HeNNA with our framework MeDeHa (Message Delivery in Heterogeneous, Disruption-prone Networks [12], [13]) , which allows message delivery across an internet consisting of different networks and involving diverse node capabilities. We show that HeNNA augments MeDeHa to use location-transparent naming and thus makes MeDeHa better equipped to support network and node heterogeneity.…”

Routing for disruption tolerant networks: taxonomy and design

“…These utility function are very useful especially when the network as well as the participating nodes are heterogeneous. Many utility functions have been presented in [15], and are thoroughly investigated and applied to heterogeneous environments in [39,40].…”

Always Best (dis-)Connected: Challenges to Interconnect Highly Heterogeneous Networks

“…MEDEHA/HENNA [20,21] is a proposal for internetworking of highly heterogeneous networks. It can interconnect infrastructure networks and MANETs, and also can work in a DTN-like mode.…”