Satellite Communications: from PEPs to DTN

Delay-/Disruption-Tolerant Networking represents an innovative way to cope with satellite communications impairments. In this view, the paper presents an in-depth analysis of implications of a DTN approach to satellite communications, focusing on these fundamental aspects: network architecture, security, and Quality of Service (QoS). For each topic, commonalities and differences between DTN and Performance Enhancing Proxies (PEPs) are highlighted, to show that the DTN architecture can be seen as a promising evolution of PEPs, at present the most widely adopted architecture. The analysis shows that DTN can effectively improve PEPs functionalities in the presence of intermittent and disruptive channels and/or a high level of network heterogeneity. In particular, DTN offers the possibility to operate with intermittent channels, a better resilience to channel disruptions, the possibility to implement both end-to-end and hop-by-hop security, and a greater flexibility in the use of advanced QoS techniques.