[Dataset] intel/home (v. 2006-04-16)

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the initial version

@MISC{intel-home-2006-04-16,
  author = {Konstantina Papagiannaki and Mark Yarvis and W. Steven Conner},
  title = {{CRAWDAD} data set intel/home (v. 2006-04-16)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/intel/home},
  month = apr,  
  year = 2006
}
					

Measurements reflect connectivity and UDP/TCP throughput
data collected from a grid of six nodes placed within three different houses.

Measurements reflect connectivity and UDP/TCP throughput 
data collected from a grid of six nodes placed within three different houses, 
2 in the United States (denoted ushome1 and ushome2) and 1 in the United Kingdom 
(denoted ukhome1).  Results have been collected for different values for 
transmission power and transmission rate, as well as 802.11a and 802.11b 
wireless devices.

A brief description of the three houses along with approximate floorplans 
(which can be downloaded from the trace intel/home/reachability/floorplan )
are shown below. 

Label    Size (ft^2)    Construction    Floors    Nodes
-------------------------------------------------------
ushome1    2,500        Wood            2        6
ushome2    2,600        Wood            3        6
ukhome1    1,500        Brick/steel     3        6

For 802.11b experiments the nodes are small form-factor 
PCs with Netgear MA701 compact flash 802.11b wireless cards. 
The nodes run Linux kernel version 2.4.19 and the hostap driver. 
For 802.11a experiments the nodes are laptops with NetGear WAG511 
CardBus 802.11a/b/g cards running Linux kernel version 2.4.26 and 
the MIT madwifi-stripped driver. All radios have omnidirectional 
antennas, and could be considered comparable to the radios that 
are likely to be integrated in future consumer electronics, 
e.g. cheap radios with basic functionality. Lastly, all three 
testbeds are homogeneous; each node consists of the exact same 
hardware to limit the impact of hardware peculiarities on 
the obtained results.

Our network setup is common among all experiments.
All nodes utilize an unused frequency that is at least five
channels away from the next occupied 802.11 frequency. To
facilitate our experiments, we utilize the 802.11 Independent
Basic Service Set (IBSS) mode, which allows all nodes to
communicate directly. However, this configuration does not
constrain the usefulness of our results to ad hoc (mesh)
topologies.

Each node is instructed to run an experiment toward 
every other node in turn. Our experiments are designed 
to assess: (i) success/loss rate, and (ii) throughput under 
different combinations of txrate and txpower. 
We further alter the node location for specific
experiments in order to quantify the impact of exact node
location, antenna orientation, and obstacles. Experiments are
carried out during the night to avoid interference from moving
people and facilitate reproducibility. Except where explicitly
stated, each result represents a single experimental run, due to
the highly time consuming nature of our experiments. Instead,
we rely on the validating runs presented in the following
subsections to lend credence to our results.

[Traceset] intel/home/reachability (v. 2006-04-16)

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the initial version

@MISC{intel-home-reachability-2006-04-16,
  author = {Konstantina Papagiannaki and Mark Yarvis and W. Steven Conner},
  title = {{CRAWDAD} trace set intel/home/reachability (v. 2006-04-16)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/intel/home/reachability},
  month = apr,  
  year = 2006
}
					

Reachability and throughput measurement from home wireless networks

Reachability: The reachability experiments assess 
link quality between each pair of nodes in the home network 
in terms of success/loss rate, and rely on a series of UDP probe 
packets sent from every node to every other node. Each probe packet 
lists the source node, as well as its number in the series. 
The size of the probe packet and the duration of each sub-experiment 
are configurable. In all experiments, link-layer retransmissions were 
disabled, the probe size was 1472 bytes, and the duration of each 
sub-experiment was 60 seconds, with a frequency of one packet 
every 500 ms. Each individual wireless link is assessed independently, 
and no simultaneous transmissions take place inside the network.

Throughput: The throughput experiments were run to assess the quality 
of layer-3 communication within the home network. Throughput was 
assessed for both TCP and UDP protocols. For our throughput experiments 
we use the same basic methodology which relies on measurements from 
all pairings of the six nodes in the testbed. Throughput is measured 
by the netperf traffic generator using 1472 byte packets. Each node 
initiates a netperf connection to every other node (in turn) and 
measures the throughput achieved over a 60 second time interval. 
Unlike the reachability experiments, the throughput experiments are 
conducted with link layer retransmission enabled (maximum of 3 retries), 
which is likely to alleviate the effect of short term degradation 
in link quality.

Autorate: UDP/TCP throughput measurements are collected for 60 second 
flows when transmitters employ autorate.

[Traceset] intel/home/multihop (v. 2006-04-16)

top

the initial version

@MISC{intel-home-multihop-2006-04-16,
  author = {Konstantina Papagiannaki and Mark Yarvis and W. Steven Conner},
  title = {{CRAWDAD} trace set intel/home/multihop (v. 2006-04-16)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/intel/home/multihop},
  month = apr,  
  year = 2006
}
					

Multihop throughput measurement from home wireless networks

Multihop: For one specific node in the testbed we setup multihop paths 
through every other node in the testbed and measure the resulting UDP 
throughput using netperf. We establish that the resulting multi-hop 
UDP throughput can be well approximated by

thr(src, dst) = 1/(1/thr(src,relay)+1/thr(relay,dst)),

where src denotes the transmitting node, dst denotes the receiving node, 
and relay denotes the node that relays traffic between the two.

Using this formula we compare the performance of the network under 
three different topologies 

(i) Direct where each node communicates with every other node using 
the direct path, 
(ii) AP-topology, where one specific node is selected to act as a relay 
between any two other nodes in the testbed, and 
(iii) Multihop-topology, where nodes communicate with each other either 
using the optimal path through the topology, where optimality captures 
minimum airtime. In this last case, we assume that paths are selected 
using Dijkstra's algorithm and link weights relay airtime, i.e. a path 
is selected such that a packet between the two nodes occupies the least 
amount of time in the network.

All experiments test performance for a single flow between two nodes 
in the testbed. There are no contending transmission occupying the network.

[Trace] intel/home/reachability/floorplan (v. 2006-04-16)

top

the initial version

@MISC{intel-home-reachability-floorplan-2006-04-16,
  author = {Konstantina Papagiannaki and Mark Yarvis and W. Steven Conner},
  title = {{CRAWDAD} trace intel/home/reachability/floorplan (v. 2006-04-16)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/intel/home/reachability/floorplan},
  month = apr,  
  year = 2006
}
					

Approximate floorplan for the three houses

Floorplan for three different houses, 
2 in the United States (denoted ushome1 and ushome2) and 
1 in the United Kingdom (denoted ukhome1).
The lines in the floorplan images reflect the (unidirectional) links 
that exhibited more than 90% loss in the reachability experiments.

three png image files

[Trace] intel/home/reachability/distance (v. 2006-04-16)

top

the initial version

@MISC{intel-home-reachability-distance-2006-04-16,
  author = {Konstantina Papagiannaki and Mark Yarvis and W. Steven Conner},
  title = {{CRAWDAD} trace intel/home/reachability/distance (v. 2006-04-16)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/intel/home/reachability/distance},
  month = apr,  
  year = 2006
}
					

Distance between each pair of nodes

Distance between each pair of nodes 
in the three houses (ushome1, ushome2, and ukhome)
in the original deployment in feet

distance in each row

[Trace] intel/home/reachability/results (v. 2006-04-16)

top

the initial version

@MISC{intel-home-reachability-results-2006-04-16,
  author = {Konstantina Papagiannaki and Mark Yarvis and W. Steven Conner},
  title = {{CRAWDAD} trace intel/home/reachability/results (v. 2006-04-16)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/intel/home/reachability/results},
  month = apr,  
  year = 2006
}
					

Reachability and Throughput Results

File names are as follows:

{House}-{Exp}-{Network}-{Traffic}-{Txrate}-{Txpower}.{Mode}.txt

- House: ushome1, ushome2, or ukhome
- Exp: original (original topology), validation (validation run), 
rotated (with nodes rotaetd by 180 degrees), or 
autorate (with autorate on)
- Network: b (802.11 b) or a (802.11 a)
- Traffic: udp or tcp
- Txrate: TX rate (e.g., 2Mbps)
- Txpower: TX power (e.g., 30mW)
- Mode: comb (for reachability/throughput experiments),
or top (for multihop throughput experiments)

All files are of the following format. 

Each row corresponds to the measurements collected from node2->node3, 
node2->node4, node2->node5, node2->node6, node2->node7, node3->node2, 
node3->node4, etc. (node1 was used to control the experiments). 
The first column of measurements corresponds to the number of UDP probes 
that were successfully received (total number of probes is 120). 
The second column captures the throughput measured from the source node 
to the destination node in Mbps.

[Trace] intel/home/multihop/results (v. 2006-04-16)

top

the initial version

@MISC{intel-home-multihop-results-2006-04-16,
  author = {Konstantina Papagiannaki and Mark Yarvis and W. Steven Conner},
  title = {{CRAWDAD} trace intel/home/multihop/results (v. 2006-04-16)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/intel/home/multihop/results},
  month = apr,  
  year = 2006
}
					

Multihop UDP Throughput Results

To assess the accuracy of approximating 2-hop 
throughput using single hop measurements, we used node2 in ukhome1 
as a transmitter and measured 2-hop throughput to every other node 
in the home using every other node as a relay. We then compared our 
estimate against the measured 2-hop value. Notice that this kind of 
analysis looks into UDP throughput alone.

File names are as follows:

{House}-{Exp}-{Network}-{Traffic}-{Txrate}-{Txpower}.{Mode}.txt

- House: ushome1, ushome2, or ukhome
- Exp: original (original topology), validation (validation run), 
rotated (with nodes rotaetd by 180 degrees), or 
autorate (with autorate on)
- Network: b (802.11 b) or a (802.11 a)
- Traffic: udp or tcp
- Txrate: TX rate (e.g., 2Mbps)
- Txpower: TX power (e.g., 30mW)
- Mode: comb (for reachability/throughput experiments),
or top (for multihop throughput experiments)

All files are of the following format. 
The first row denotes the pairs of nodes tested and 
each other row has an experiment descriptor that indicates 
the type of topology tested.

[Author] Konstantina Papagiannaki

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[Author] Mark Yarvis

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[Author] W. Steven Conner

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[Paper] papagiannaki-home

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Anecdotal evidence suggests that home wireless networks may be unpredictable 
despite their limited size. In this work, we deploy six-node wireless testbeds 
in three houses in the United States and the United Kingdom.We examine the 
quality of links in home wireless networks and the effect of (i) transmission 
rate, (ii) transmission power, (iii) node location, (iv) type of house, and (v) 
802.11 technology. We provide empirical evidence suggesting that homes are 
challenging environments for wireless communication.Wireless links in the home 
are highly asymmetric and heavily influenced by precise node location, 
transmission power, and encoding rate, rather than physical distance between 
nodes. In our measurements, many links were unable to utilize the maximum 
transmission rate of the deployed 802.11 technology, and a few provided no 
connectivity at all. These results suggest that creating an AP-based topology 
with maximum coverage and throughput in this environment is challenging. Our 
findings have implications on the design of future home wireless networks and 
requirements for future wifi-enabled consumer electronic devices. We show that 
coverage and performance can be improved using a multi-hop topology, implying 
that mesh capabilities may actually be needed in consumer electronics for 
seamless connectivity across the home.