[Dataset] umass/long_distance (v. 2007-06-01)

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the initial version

@MISC{umass-long_distance-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} data set umass/long_distance (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance},
  month = jun,  
  year = 2007
}
					

Our experiments consisted of 802.11g wireless network throughput
measurements in various overlapping ad-hoc node configurations
in order to better understand interference when using yagi
antennas to extend the range of the wireless transmission.

With the increasing popularity of 802.11 wireless technology, 
such equipment has recently been used to set up long distance links 
for wireless mesh networks. To be able to increase the range of 
802.11 equipment directional antennas are required. 

We measured the effects of wireless interference on throughput.
Our experiments consisted of 802.11g wireless network throughput
measurements in various overlapping ad-hoc node configurations 
in order to better understand interference when using yagi 
antennas to extend the range of the wireless transmission. 
We were particularly interested in the behavior at the multi-hop 
node, which has 2 antennas in close proximity as would be required
on a communications tower.

The test equipment consists of 4 Lenovo T60 notebooks
running slackware Linux with the 2.6 kernel, and using
ProximWLAN adapters (atheros chipset), and we are using
the opensourceMadWifi drivers for the wireless cards.
These PCMCIA cards are connected to an external Hyperlink
Yagi antenna to extend their range. We make
a special point to note that MadWifi driver includes a
proprietary HAL that controls many key aspects of the
adapters, one of which being the use of measured RSSI
values to sense whether the channel is in use, contrasted
with the RTS/CTS scheme that other wireless cards use
to sense the channel. We suspect that this channel contention
scheme leads to some unexpected behavior in our
ad-hoc test network.

We used Iperf3, a tool to measure maximum TCP bandwidth, to 
investigate how the different setups would change the overall
performance of the multi-hop link. Additional tcpdump4 traces
were taken in order to obtain more detailed information on a
per-packet level. Each measurement ran for 30 seconds and
was repeated 10 times. We decided to repeat each measurement
10 times to average out the effects of any short-term
artifacts on the wireless channel.

For each test we vary the channels 1-6 on pair2 while keeping pair1 
on channel 1. It should be noted that we tested overlap up to 
5 channels of separation because after that there is such minimal
overlap in the spectrum, that the results would not vary.

[Traceset] umass/long_distance/interference (v. 2007-06-01)

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the initial version.

@MISC{umass-long_distance-interference-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace set umass/long_distance/interference (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference},
  month = jun,  
  year = 2007
}
					

Our experiments consisted of 802.11g wireless network throughput
measurements in various overlapping ad-hoc node configurations 
in order to better understand interference when using yagi antennas 
to extend the range of the wireless transmission.

Our experiments consisted of 802.11g wireless network throughput
measurements in various overlapping ad-hoc node configurations 
in order to better understand interference when using yagi antennas 
to extend the range of the wireless transmission.

A. Node Location and Spatial Separation

As shown in [Figure: Measurement setup], Node 4 was set up in 
3 different locations while Node 1 and the multi-hop node 
(composed of Nodes 2 and 3) stayed in fixed locations. 
In the multi-hop node the only change that was made for the 
different setups was the orientation of Node 3's antenna 
to line it up with Node 4's antenna. For all measurements except 
one the two antennas at the multi-hop node were placed 4 feet 
from each other in the horizontal plane, with no separation 
in the vertical plane. In the setup for the final measurement 
we also separated the two antennas at the middle node by 4 feet 
in the vertical plane. We assumed that a distance of 4 feet 
would be a separation distance typical of installations 
on communication towers.

Five different setups, which are explained in more detail in
the following, were used for the throughput measurements. In
setup 1, all nodes are located along a virtual line. The two
antennas at the multi-hop node are mounted in a way that
they point directly away (180 ) from each other. In setup 2,
link 2 is shifted by 45, resulting in a 135  angle between
the main lobes of the two antennas at the multi-hop node.
Link 2 is shifted by 90  in setup 3, which also results in a
90  separation of the antennas. Setup 4 is identical to setup
3 with the difference that the polarization of the antennas of
link 2 is changed from horizontal to vertical. This is achieved
by rotating the mounting of the Yagi antennas by 90  in
the horizontal plane. Setup 5 is identical to setup 1 with the
difference that the antennas were not only separated by 4 feet
in the horizontal but also by 4 feet in the vertical plane.

B. Transport Scenario

We performed measurements where data was transmitted in two 
different ways.  

- N4 -> N3 | N2 -> N1: Here, N4 and N2 are sending data
simultaneously to N3 and N1, respectively.

- N4 -> N3 -> N2 -> N1: N4 is sending data all the way
to N1 in this scenario. Thus, routing between N2 and N3
is enabled.

We chose this specific routing configuration for several reasons.
In the first scenario we want to investigate the interference
that is caused at a multi-hop node with directional antennas 
when one radio is receiving while the other one is sending. 
In the second scenario, we were interested in studying the effects 
of concurrent forwarding on the N1-N2 and N3-N4 links, as well as 
the effects of routing on the wired link 3 in the multi-hop node. 
The second case is interesting since in many cases data will be 
routed through the multi-hop node between the two end nodes. 
For example, in the case where such a multi-hop node is used 
to allow data transmission from a remote sensor network. 
Here, the multi-hop node is neither a source nor a sink. 
The first case reflects a scenario in which the multi-hop node also 
acts as a source or a sink. 

C. Baseline Measurements

We performed two preliminary measurements in a single link setup 
to measure the maximum throughput on that link without any 
interference from the other link. The first measurement
was executed in the same open field where all multi-link
measurements were performed. We ran an Iperf measurement
on one link only, while the other one was idle, which resulted
in 27 Mbps of average throughput. This throughput value
is the upper limit for the multi-hop measurements. In the
second setup we were interested how the throughput would
change on a much longer link. Therefore, we set up a link
of approximately 1 Mile in hilly terrain. Here, the Iperf
measurement resulted in an average throughput of 25.54 Mbps.

[Trace] umass/long_distance/interference/test1 (v. 2007-06-01)

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the initial version

@MISC{umass-long_distance-interference-test1-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test1 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test1},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
In this test we look at the interference when two nodes
are sending towards a multi-hop node and the multi-hop
node is recieving on both interfaces.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 1: N4 -> N3 | N2 -> N1

In this test we look at the interference when two nodes
are sending towards a multi-hop node and the multi-hop
node is recieving on both interfaces. The nodes are in a
straight line, 180 degree. Nodes 1 and 4 transmit at the same
time towards the center node. We see a steady increase
in throughput as we extend the channel seperation. The
signal strength did not match the throughput results
exactely, it increased at a separation of 2 and 3, and
dropped down to 20-30 RSSI for the remainder.

[Trace] umass/long_distance/interference/test2 (v. 2007-06-01)

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the initial version

@MISC{umass-long_distance-interference-test2-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test2 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test2},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
In this test we look into interference when two nodes
transmit at the same time.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 2: N4 -> N3 | N2 -> N1

In this test we look into interference when two nodes
transmit at the same time. Nodes 2 and 4 transmit at
the same time and the multi-hop node is sending on one
interface and recieving on the other. The antennas at
the center node are separated by 5 minutes. The nodes are in
a straight line, 180 degree. We noticed that there was a lot of
variance in the throughput on this test, and we suspect
that this may be due to the way that the wireless interfaces
contend for the channel. Another reason for the variance
could be that node 4 is overshooting the multi-hop node
and is being sensed at node 1 as node1 is recieving from
node2. The throughput is consistently higher on the
pair2 network which seems to support this idea. Also, on
channel 4 pair2 had throughput upwards of 24 Mbps, but
all of a sudden around run 7 of 10 it seemed to lose the
channel and pair1 started to take over. This is why there
is such a large variation at a channel seperation of 3.

[Trace] umass/long_distance/interference/test3 (v. 2007-06-01)

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the initial version

@MISC{umass-long_distance-interference-test3-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test3 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test3},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
In this test we have configured the multi-hop node as a
gateway for each end node.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 3: N4 -> N3 -> N2 -> N1

In this test we have configured the multi-hop node as a
gateway for each end node, and so node 4 is running the
iperf client, and node 1 is running the iperf server. The
nodes are in a straight line, 180 degree. And the two nodes at
the center are spaced about 5 minutes apart. We experienced a
throughput of 4.3 Mbps on channel 1, poor in comparison,
but as the channels separate the throughput steadily
grows to 27 Mbps

[Trace] umass/long_distance/interference/test4 (v. 2007-06-01)

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the initial version

@MISC{umass-long_distance-interference-test4-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test4 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test4},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
In this configuration we create a 135 degree angle between
nodes 3 and 4 by rotating node 4 by 45 degree.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 4: N4 -> N3 | N2 -> N1

In this configuration we create a 135 degree angle between
nodes 3 and 4 by rotating node 4 by 45 degree. No routing is
used in this test and nodes 4 and 2 transmit at the same
time. The antenna's at the center are spaces 5 minutes apart. 
The performace is slightly better, definately more consistent
at this angle, rather than directly facing each other yet it
is worse on channel 2. Overall this angle is much better
than the 90 degree setup which had 5 Mbps on channel 1.

[Trace] umass/long_distance/interference/test5 (v. 2007-06-01)

top

the initial version

@MISC{umass-long_distance-interference-test5-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test5 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test5},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
This setup is a 135 degree test similar to test 4, except that
we have enabled routing via the multi-hop node.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 5: N4 -> N3 -> N2 -> N1

This setup is a 135 degree test similar to test 4, except that
we have enabled routing via the multi-hop node. The
antenna's at the center are about 5 minutes apart. The iperf
server is run on node 1 and node 4 is the client. At this
antenna orientation we have much better performance
that in the 180 degree case, 13 Mbps vs. 4 Mpbs on channel
1. We think that this is due to the fact that the antenna
pattern of the yagi's has a weak spot right at the 135 degree
section (off center), and so we are not causing as much
interference with the sender at the multi-hop node (node
2).

[Trace] umass/long_distance/interference/test6 (v. 2007-06-01)

top

the initial version

@MISC{umass-long_distance-interference-test6-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test6 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test6},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
In this test we alter the antenna orientation to 90 degree off
center, between node 3 and 4.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 6: N4 -> N3 | N2 -> N1

In this test we alter the antenna orientation to 90 degree off
center, between node 3 and 4. The antenna's at the center are 
5 minutes apart. Again, both nodes are transmitting simultanously. 
Pair 1 seems to dominate the channels this time, and has much 
higher throughput (25 Mbps for pair1 vs. 5 Mbps for pair2). 
The sidelobes of the antenna are largest at 90 degree so this 
could account for the poor performance on pair2. It seems thought 
that in the scenario's where there are 2 simultaneous transmissions 
and no routing, that one side seems to dominate.

[Trace] umass/long_distance/interference/test7 (v. 2007-06-01)

top

the initial version

@MISC{umass-long_distance-interference-test7-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test7 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test7},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
This is a routing test which was conducted with a 90 degree
antenna orientation between nodes 3 and 4.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 7: N4 -> N3 -> N2 -> N1

This is a routing test which was conducted with a 90 degree
antenna orientation between nodes 3 and 4. The antenna's
at the center are 5 minutes apart. Routing is enabled this time,
with node 4 as the iperf client and node 1 as the server.
The throughput here was a little worse than the 135 degree
case, 10 Mbps here vs. 14 Mbps at 135 degree, yet much
better than the 180 degree case which had a throughput of 3.5
on channel 1. We believe that the better results at low
channel separations is due to orientation angle, and also
in that when routing is enabled, the networks negotiate
the channel better and share the bandwidth more evenly
even with the side-lobe overlap.

[Trace] umass/long_distance/interference/test8 (v. 2007-06-01)

top

the initial version

@MISC{umass-long_distance-interference-test8-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test8 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test8},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
This test was conducted at a 90 degree orientation, and also
the pair2 network has changed polarization of the yagi
antennas from vertical to horizontal.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 8: N4 -> N3 | N2 -> N1

This test was conducted at a 90 degree orientation, and also
the pair2 network has changed polarization of the yagi
antennas from vertical to horizontal. The pair1 network
is still at the vertical orientation. The antenna's at the
multi-hop node are separated by 5 minutes. Both Nodes 2 and 4
transmit simultaneously. In this case the channel is shared
a little better than in test 7 where the only difference
was in the polarization. But here pair2 dominates the
channels an has higher throughput, except on channel 1
they are both right at 15 Mbps. In test 7 on channel 1
both pairs were at a difference of 20 Mbps. This suggests
that the polarization has a large effect when operating on
the same channel.

[Trace] umass/long_distance/interference/test9 (v. 2007-06-01)

top

the initial version

@MISC{umass-long_distance-interference-test9-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test9 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test9},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
This test was conducted at a 90 degree orientation with opposite
polarizations on each network.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 9: N4 -> N3 -> N2 -> N1

This test was conducted at a 90 degree orientation with opposite
polarizations on each network. Pair2 is set to horizontal
polarization while pair1 is vertical. The antenna's at the
multi-hop node are separated by 5 minutes. Node 4 transmits
to Node 1 by routing through the multi-hop node. This
result is very similar to the 135 degree test when routing is enabled.
Routing in this case seems to make both networks
share the bandwidth regardless of the polarization.

[Trace] umass/long_distance/interference/test10 (v. 2007-06-01)

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the initial version

@MISC{umass-long_distance-interference-test10-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test10 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test10},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
This test was performed at 180 degree and both networks were
set to the same vertical polarization.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 10: N4 -> N3 | N2 -> N1

This test was performed at 180 degree and both networks were
set to the same vertical polarization. The Height of the
antenna's was altered so that pair2 was at an elevation of
11 minutes and pair1 was at an elevation of 2 minutes. We wanted to see
if this would have an effect on interference at the middle
node. Nodes 2 and 4 transmitted simultaneously. The
performance was a little bit worse than in test 3, the 180 degree
case with no additional adjustments. This is most likely
due to outside interference due to the fact that the field
we were testing in became a parking lot for an event, and
the influx of cars on this occasion cause unmeasureable
effects on the results. We repeat this test again in test 12.

[Trace] umass/long_distance/interference/test11 (v. 2007-06-01)

top

the initial version

@MISC{umass-long_distance-interference-test11-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test11 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test11},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
This test was performed at 180 degree and both networks were
set to the same vertical polarization.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 11: N4 -> N3 -> N2 -> N1

This test was performed at 180 degree and both networks were
set to the same vertical polarization. The Height of the
antenna's was altered so that pair2 was at an elevation of
11 minutes and pair1 was at an elevation of 2 minutes. We wanted 
to see if this would have an effect on interference at the middle
node. Routing was enabled but performance was poor
due to outside factors, the influx of cars on this occasion
cause unmeasureable effects on the results. We repeat
this test again in test 13.

[Trace] umass/long_distance/interference/test12 (v. 2007-06-01)

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the initial version

@MISC{umass-long_distance-interference-test12-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test12 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test12},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
Simultaneous transmission height difference test - repeat
of 10. Pair2 really dominated this time.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 12: N4 -> N3 | N2 -> N1

Simultaneous transmission height difference test - repeat
of 10. Pair2 really dominated this time. The throughput
on pair2 was much better than in test3, but pair1's
thoughput was really poor. Again, channel contention
algorithms have a big part in this phenomenon. Pair2
seems to have grabbed the bandwidth and stuck with it.
Pair1's gains came during intervals of the 10 runs when
pair2 stopped sending breifly to start another run.

[Trace] umass/long_distance/interference/test13 (v. 2007-06-01)

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the initial version

@MISC{umass-long_distance-interference-test13-2007-06-01,
  author = {Timothy Ireland and Adam Nyzio and Michael Zink and Jim Kurose},
  title = {{CRAWDAD} trace umass/long_distance/interference/test13 (v. 2007-06-01)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/umass/long_distance/interference/test13},
  month = jun,  
  year = 2007
}
					

We measured 802.11g wireless network throughput in various 
overlapping ad-hoc node configurations using yagi antennas. 
This test is a Routing height separated test - repeat of 11.

In each of 13 tests, nodes 1 and 2 are on essid pair1, and nodes 3 
and 4 are on essid pair2, this allows us to force the traffic 
to be routed through the multi-hop node instead of the overlap just 
reaching the far reciever in some cases. For each of 5 network 
configurations, we conducted 2 experiments; we tested througput 
in a 2-hop routing configuration (where we consider the middle node 
as a virutal single node), and we tested throughput in a non-routing 
configuration where 2 nodes, one from each essid, are sending at 
the same time. In the non-routing test the multi-hop node is sending 
on one interface and recieving on the other. 

Test 13: N4 -> N3 -> N2 -> N1

Routing height separated test - repeat of 11. Here we
actually do worse than in the 180 degree non-height separated
routing scenario. We are not really sure why, we expected
a benefit.

[Author] Timothy Ireland

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[Author] Adam Nyzio

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[Author] Michael Zink

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[Author] Jim Kurose

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[Paper] ireland-long-distance

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