Hello.

By design of the bundle protocol, synchronized clocks are mandatory in a DTN. Since that is heavy constrain, I am working on solutions to mitigate the issue or provide time-synchronization even in losely connected networks. Basically, there are two approaches. One of them is the Age Block Extension which allows to track the age of a bundle without a correct clock. Since this might be quite inaccurately, IBR-DTN provides a mechanism to synchronize clocks. The approach to do this is described in this paper: http://dl.acm.org/citation.cfm?doid=2348616.2348618.

To enable time-sync you need at least one reference clock (master) in your network.

# Master configuration
time_reference = yes
time_discovery_announcements = yes

The best way is to choose a node with a NTP (or something equal) as master.
Sich a master will announce its time data to slaves.

# Slave configuration
time_reference = no
time_discovery_announcements = yes
time_synchronize = yes

If the daemon runs as root, it can set the nodes clock if synchronized

time_set_clock = no

Be aware of that existing code in the releases is very experimental and not completly polished to work under all circumstances. There are known bugs which are already solved in the master GIT branch, but due to larger changes not in the 0.10.x releases.

Kind regards,
Johannes

Am 23.09.2013 14:40, schrieb Shyam B: