[Traceset] isti/rural/packet_loss (v. 2007-12-19)

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the initial version.

@MISC{isti-rural-packet_loss-2007-12-19,
  author = {Paolo Barsocchi and Gabriele Oligeri and Francesco Potortì},
  title = {{CRAWDAD} trace set isti/rural/packet_loss (v. 2007-12-19)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/isti/rural/packet_loss},
  month = dec,  
  year = 2007
}
					

We conducted a series of measurements for relating transmission distance 
and packet loss on a Wi-Fi network in rural areas.

We disabled fragmentation, RTS/CTS, retransmissions (ARQ) and 
dynamic rate switching. We used different fixed speeds of 1, 2, 5.5 and 
11 Mb/s, with three fixed frame lengths (500, 1000, 1500 bytes), 
for different transmitter-receiver distances.

By disabling ARQ, the MAC layer transmits each packet only once, 
rather than trying to retransmit a frame up to 8 times after a loss. 
This means that we sampled the channel at a constant rate of 
200 frames per second, thus accurately measuring the frame error 
process in the time domain, using 200,000 frames for each measure. 
Notice that the procedure described makes the measurement process 
independent of the MAC protocol, and dependent only on the channel 
and the used hardware. 

The rural environment was a wide uncultivated field with an unobstructed 
line of sight, far from buildings, cell phone antennas and power lines.

We wrote Vbrsr, a pair of programs for sending and receiving frames 
with the aim of collecting statistics about frame errors and power levels, 
which is released with a free software copyright license and is available 
for download at http://wnlab.isti.cnr.it/paolo/measurements/Software.html.

[Trace] isti/rural/packet_loss/navacchio (v. 2007-12-19)

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the initial version

@MISC{isti-rural-packet_loss-navacchio-2007-12-19,
  author = {Paolo Barsocchi and Gabriele Oligeri and Francesco Potortì},
  title = {{CRAWDAD} trace isti/rural/packet_loss/navacchio (v. 2007-12-19)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/isti/rural/packet_loss/navacchio},
  month = dec,  
  year = 2007
}
					

These traces are the data measured in Navacchio (Pisa) in April, 2006 
using two laptops in 802.11 ad hoc mode at different distance on a wide
uncultivated field.

These are the data measured in Navacchio (Pisa) in April, 2006 using two
laptops in 802.11 ad hoc mode at different distance on a wide
uncultivated field.  The laptops are two IBM Thinkpad R40e laptops
(Celeron 2 GHz with 256 MB ram running Debian Linux with a 2.6.8
kernel), equipped with CNet CNWLC-811 wireless cards and standard
drivers.

Retransmission, RTS/CTS and fragmentation are all disabled, long
preambles are used.  Frames are sent to the network card with a 5ms
intertransmission time for 11, 5.5 and 2Mb/s speeds, 10ms for the 1Mb/s
speed.  Notice that frames with data length 1500B are longer than 5ms at
2Mb/s and longer than 10ms at 1MB/s: in these cases the network card
transmits the packets back-to-back.

Each file name is built like this: rcv_SPEED_DISTANCE_LENGTH

where SPEED is the transmission speed (1, 2, 5.5, 11 Mb/s),
DISTANCE is the distance between the transmitter and the receiver
and LENGTH is the frame length (500, 1000, 1500 bytes).

The fields marked with an asterisk (*) below are always 0, because the
network card used for the measurements in this directory cannot give
these statistics.

Each line contains these fields:
 - receive time, or 0 when packet is not received at all
 - lenght of the frame in bytes to data: to obtain the whole frame
   lenght one must add an LLC/SNAP header, CRC and MAC header. There are
   three data lengths: 500, 1000 and 1500 bytes.  The respective frame
   durations can be computed as:

		+-------+-------+-------+-------+-------+
		|len[ms]| 1 Mb/s| 2 Mb/s|5.5Mb/s|11 Mb/s|
		+-------+-------+-------+-------+-------+
		| 500 B | 5.154 | 2.954 | 1.555 | 1.154 |
		+-------+-------+-------+-------+-------+
		|1000 B | 9.154 | 4.954 | 2.282 | 1.518 |
		+-------+-------+-------+-------+-------+
		|1500 B |13.154 | 6.954 | 3.009 | 1.881 |
		+-------+-------+-------+-------+-------+

 - sequence number starting from 0
*- quality level read from the network card
 - signal level read from the network card: multiply by 0.6 to get dB
*- noise level read from the network card
 - status: 1 for lost frames, 0 for received frames
*- number of corrupted bits in frames received with wrong CRC

[Trace] isti/rural/packet_loss/aggregated (v. 2007-12-19)

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the initial version

@MISC{isti-rural-packet_loss-aggregated-2007-12-19,
  author = {Paolo Barsocchi and Gabriele Oligeri and Francesco Potortì},
  title = {{CRAWDAD} trace isti/rural/packet_loss/aggregated (v. 2007-12-19)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/isti/rural/packet_loss/aggregated},
  month = dec,  
  year = 2007
}
					

These traces are aggregated statistics on data measured in Navacchio at
the beginning of 2006 using two laptops in 802.11 ad hoc mode at
different distances on a wide uncultivated field.

These data are aggregated statistics on data measured in Navacchio at
the beginning of 2006 using two laptops in 802.11 ad hoc mode at
different distances on a wide uncultivated field.

Each file contains data relative to a single transmission speed: 1, 2,
5.5, 11 Mb/s.  Retransmission, RTS/CTS and fragmentation are all
disabled, long preambles are used.

A line in a file is relative to 1000 consecutive frames sent with 
a 5ms intertransmission time for the three top speeds, 10ms for the lowest, 
so each line is relative to a 5s or 10s measurement, depending on speed.  

Each line contains these fields:
 - sequence number starting from 0 relative to a ~15min measurement
 - lenght of the frame in bytes: to obtain the whole frame lenght one
   must add an LLC/SNAP header, CRC and MAC header.  There are three
   lengths: 500, 1000 and 1500 bytes.  The frame lengths in ms are:

		+-------+-------+-------+-------+-------+
		|len[ms]| 1 Mb/s| 2 Mb/s|5.5Mb/s|11 Mb/s|
		+-------+-------+-------+-------+-------+
		| 500 B | 5.154 | 2.954 | 1.555 | 1.154 |
		+-------+-------+-------+-------+-------+
		|1000 B | 9.154 | 4.954 | 2.282 | 1.518 |
		+-------+-------+-------+-------+-------+
		|1500 B |13.154 | 6.954 | 3.009 | 1.881 |
		+-------+-------+-------+-------+-------+

   notice that the cases of lenght 1500 B exceed 5ms at 2Mb/s and exceed
   10ms at 1MB/s: in these two cases the packets have been sent with the
   smallest possible intertranmission interval.
 - signal level presented by the network card: multiply by 0.6 to get dB
 - frame error rate

[Author] Paolo Barsocchi

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[Author] Gabriele Oligeri

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[Author] Francesco Potortì

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