On Thu, Mar 25, 2010 at 10:52 AM, <[email protected]> wrote: > Spam detection software, running on the system > "mail.Millennium.Berkeley.EDU", has > identified this incoming email as possible spam. The original message > has been attached to this so you can view it (if it isn't spam) or label > similar future email. If you have any questions, see > the administrator of that system for details. > > Content preview: Hi, I am an honours year student at Glasgow Caledonian > University > and my undergraduate dissertation involves me investigating clustering and > data aggregation in wireless sensor networks. One of the metrics that I am > keen on collecting is network lifetime, I have read several different > definitions > of what constitutes network lifetime and I have decided that the best way > to collect this data would be to add a debug statement that printed the time > a node died at, however, I am unsure where I could add such a debug message. > I looked through various system files as well as those relating to the > build/pc > (I am using the TOSSIM simulator rather than real nodes) and couldn't find > an appropriate point to put this debug message. [...]
There are many approximations to node lifetime. Many people compute the number of transmissions/receptions and use that to approximate the energy spent by a node and compute its lifetime. If radio rx/tx are the dominant energy sinks on a node, and you happen to be using an energy-saving MAC that keeps the radio on mostly during rx/tx, this is a crude approximation of node energy expenditure. You can use this to compute how long a node will last given a certain amount of energy available in the battery. If you are limited to TOSSIM, you might be able to count the pkt rx/tx if you want to take this approach. The best way to know how long a node will remain alive is by measuring it directly. TOSSIM with energy extension (there was a good one for TinyOS 1.x) will allow you to measure energy directly. - om_p _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
