## 3 Survey Results
### Lifetime and Energy  
Table 4 describes energy usage and the target lifetime of the analyzed deployments. \begin{table}
\begin{tabular}{l l l l l l l} \hline \hline
**Nr** & **Codename** & **Lifetime, days** & **Energy source** & **Sleep** & **time,** & **Duty cycle, \%** & **Powered-motes** \\  & & & & & **sec** & & **prest** \\ \hline
1 & Habitats & 270 & battery & 60 &? & yes, gateways \\
2 & Minefield &? & battery &? &? & yes, all \\
3 & Battlefield & 5–50 & battery & varies & varies & yes, base station \\
4 & Line in the sand &? & battery and solar &? &? & yes, root \\
5 & Counter-sniper &? & battery & 0 & 100 & no \\
6 & Electro-shepherd & 50 & battery &? & \(<1\) & no \\
7 & Virtual fences & 2 h 40 min & battery & 0 & 100 & no \\
8 & Oil tanker & 82 & battery & 64,800 & \(<1\) & yes, gateways \\
9 & Enemy vehicles &? & battery &? &? & yes, mobile nodes \\
10 & Trove game &? & battery &? &? & yes, base station \\
11 & Elder RFID &? & battery & 0? & 100? & yes, base station \\
12 & Murphy potatoes & 21 & battery & 60 & 11 & yes, base station \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Deployments: lifetime and energy. Figure 4: **Sensor sampling rate used in deployments—Low duty cycle applications with sampling rate below 1 Hz are the most popular; however, high-frequency sampling is also used; the ranges 10–100 Hz and 10–100 kHz are popular. **  
Target lifetime is very dynamic among applications, from several hours to several years. Long-living deployments use a duty-cycle below 1%, meaning that sleep mode is used 99% of the time. Both, very short and very long, sleeping periods are used: from 250 milliseconds up to 24 hours. Operating systems should provide effective routines for duty-cycling and have low computational overhead. A significant part of deployments (more than 30%), especially in the prototyping phase, do not concentrate on energy efficiency and use a 100% duty cycle. _Design rule 6_: The option, \"automatically activate sleep mode whenever possible\", would decrease the complexity and increase the lifetime for deployments in the prototyping phase and also help beginner sensor network programmers. \begin{table}
\begin{tabular}{l l l l l l l} \hline \hline
**Nr** & **Codename** & **Lifetime, days** & **Energy source** & **Sleep sec** & **time,** & **Duty cycle, \%** & **Powered-motes present** \\ \hline
13 & Firewxnet & 21 & battery & 840 & 6.67 & yes, gateways \\
14 & AlarmNet &? & battery &? & configurable & yes, base stations \\
15 & Ecuador Volcano & 19 & battery & 0 & 100 & yes, base station \\
16 & Pet game &? & battery &? &? & yes, base station \\
17 & Plug & - & power-net & 0 & 100 & yes, all \\
18 & B-Live & - & battery & 0 & 100 & yes, all \\
19 & Biomotion & 5 h & battery & 0 & 100 & yes, base stations \\
20 & AID-N & 6 & battery & 0 & 100 & yes, base station \\
21 & Firefighting & 4+ & battery & 0 & 100 & yes, infrastructure \\  & & & & & & \\
22 & Rehabil &? & battery &? &? & yes, base station \\
23 & CargoNet & 1825 & battery & varies & 0.001 & no \\
24 & Fence monitor &? & battery & 1 &? & yes, base station \\
25 & BikeNet &? & battery &? &? & yes, gateways \\
26 & BriMon & 625 & battery & & 0.55 & no \\
27 & IP net &? & battery &? & 20 & yes, base station \\
28 & Smart home &? & battery &? &? & yes \\
29 & SVATS & unlimited & power-net & not & - & yes, all \\  & & & & implemented & & \\
30 & Hitchhiker & 60 & battery and solar & 5 & 10 & yes, base station \\
31 & Daily morning &? & battery & 0? & 100? & yes, base station \\
32 & Heritage & 525 & battery & 0.57 & 0.05 & yes, base station \\
33 & AC meter &? & power-net &? &? & yes, gateways \\
34 & Coal mine &? & battery &? &? & yes, base station? \\
35 & ITS &? & power-net? & 0? & 100? & yes, all \\
36 & Underwater &? & battery &? &? & no \\
37 & PipeProbe & 4 h & battery & 0 & 100 & yes, base station \\
38 & Badgers & 7 & battery &? & 0.05 & no \\
39 & Helens volcano & 400 & battery & 0? & 100? & yes, all \\
40 & Tunnels & 480 & battery & 0.25 &? & yes, base stations \\ \hline \hline \end{tabular}
\end{table}