Chimera v.0.9 Release update
In Chimera version 0.9, we have added several optimization parameters
to the library. Here is the summery of these optimizations:
- Alternate routing table entries: In previous versions
each node only had one choice for routing to a specific destination in
its routing table. In this version we added multiple alternate entries
for each routing table entry. Number of entries can be set in route.h
by the MAX_ENTRY. Chimera routing sub-system choose the best node as
its next hop among all possible entires based on the destination's link
quality and latency. Poor entires (entries with link quality less than
%30 average success rates) will be replaced with new nodes as node
learns about them.
- Chimera
Network layer updates each host entry success rate based on the
successful message delivery. The host success average is calculated
based on the defined history window, SUCCESS_WINDOW, which is defined
in host.h.
- Quantification of good or bad link quality can be set in host.h
by GOOD_LINK and BAD_LINK respectively in host.h.
- Optional acknowledgment: In version 0.9 we introduced the
optional message type acknowledgment. Each message type can be defined
to be acknowledged or not by the recipient at the time that message is
registered in chimera messaging subsystem, by calling chimera_register.
Please check the chimera.h file for more detail.
- Message delivery retries: In previous versions failure of single
message delivery was an indication of node failure by the sender. This
would led to removal of the destination from routing table and leafset.
This mechanism has changed by adding multiple retries to failure
message delivery in order to consider possible network congestion.
- message_send(...), chimera_register(...),and
network_send(...) function prototypes have changed.
- Future security enhancements: several fields added to various
chimera structures for future overlay security enhancement.
Rama Alebouyeh

Last updated 02/16/06