[Dataset] ucsd/cse (v. 2008-08-25)

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the initial version

@MISC{ucsd-cse-2008-08-25,
  author = {Yu-Chung Cheng},
  title = {{CRAWDAD} data set ucsd/cse (v. 2008-08-25)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/ucsd/cse},
  month = aug,  
  year = 2008
}
					

To characterize the sources of delay in 802.11 production network, 
we collected comprehensive traces of wireless activity in the UCSD 
Computer Science building.

To characterize the sources of delay in 802.11 production network, 
we collected comprehensive traces of wireless activity in the UCSD 
Computer Science building. The traces was collected on Thursday,
January 11, 2007.

The production 802.11 network consists of 40 Avaya AP-8 802.11 b/g 
access points covering four floors and the basement. The APs are 
identically confiured (except for their channel assignment) and 
support both 802.11b and 802.11g without encryption.

Our CSE wireless network has 40 APs. Their locations are in [labels.txt] 
and five .png files - [1st floor], [2nd floor], [3rd floor], [4th floor], 
and [basement].

We use the Jigsaw system described in [cheng-jigsaw] to collect 
the traces. Jigsaw is a distributed wireless monitoring platform 
that we have deployed in our department building to monitor the 
production 802.11 network. 

The hardware monitors consist of 192 radios interspersed between
the infrastructure APs. The radios passively monitor the
wireless network and report all wireless events across location, 
channel, and time via a private wired network to a back-end storage
server. Jigsaw merges and time synchronizes these separate radio
traces into a single, global uni ed trace. Moreover, Jigsaw performs
this operation in real time; a single 2.2Ghz AMD Opteron server 
can synchronize one minute of raw trace data in under 15 seconds.

We configure Jigsaw to capture the first 120 bytes of each wireless 
frame. As a result, the aggregate monitor traffic from all radios 
ranges from 2-10Mbps and is roughly five times the amount of production 
wireless traffic.

The last 3 octest of MAC addresses except 0:0:0 are anonymized but 
the OUIs are preserved. All IP addresses in IP header or payload are 
anonymized as well except the UCSD wireless subnet prefix 
(128.54.42/16, 42.0.0.0/16) and private addresses. We do not preserv 
any other IP prefixes. Everything beyond TCP, UDP, and DHCP header 
is removed. Also we do not recompute the IP/TCP checksums.

Please be careful that the wired packet and the wireles packets are not 1-to-1 match:

    * Every wired packet may have many multiple 802.11 retransmissions.
    * APs only forward 802.11 data frames. Management, control, NULL frames only exist in 802.11 network.
    * The sniffers may pick up non-CSE AP signals. Similarly, the sniffers may miss CSE packets.
    * The wired gateway forwards broadcast traffic among other two nearby bulidings wireless VLAN.

[Traceset] ucsd/cse/jigsaw (v. 2008-08-25)

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the initial version.

@MISC{ucsd-cse-jigsaw-2008-08-25,
  author = {Yu-Chung Cheng},
  title = {{CRAWDAD} trace set ucsd/cse/jigsaw (v. 2008-08-25)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/ucsd/cse/jigsaw},
  month = aug,  
  year = 2008
}
					

We used Jigsaw - a tool for analyzing wireless traffic -  to collect comprehensive 
traces of wireless activity in the UCSD Computer Science building.

1. Software

Jigsaw is a tool for analyzing wireless traffic across locations, channels, 
time, and protocol layers. It takes traces from multiple sniffers at distinct 
vantage points, identifies and synchronize the duplicate wireless frames 
in the traces, rebuild link layer and transport layer conversasions. This version 
also includes a madwifi driver patch that reduces the overhead of excessive 
logging of PHY and CRC error events. Jigsaw is available under GPL licence.

2. Hardware

The guts of our wireless node/sensor is a Soekris net4801 or net4826 embedded 
computer, which has a 266 Mhz 586 class CPU (Geode) single chip processor. 
The 4801 board includes one Compact Flash slot, three 10/100 ethernet ports, 
128 Megabytes of RAM, serial ports, MiniPCI/PCI slot. In addition, 4801 has 
IDE port and two USB 1.1 ports. 4826 can be powered over Ethernet. Most of 
our nodes are 4826 boxes.

The Compact Flash slot is loaded with a Compact Flash card (4801 has 256M, 
4826 has 64M), used to store the moderately patched Pebble Linux image and 
related files. In normal operation the card is mounted in read-only mode 
to reduce wear and help ensure filesystem consistency in the face of power outages. 
A small portion of the memory is mounted for RW file system access. Each node 
is equipped with two Atheros-based 802.11 a/b/g wireless cards. Two NICs enable 
a broader range of experiments. The radio is attached to a 5dBi omni-directional 
attenna. We use heavily patched versions of the Atheros MadWiFi driver for these radios.

Originally, the 4801 has a 20 Gigabyte (minimum) IDE hard disk. But we found 
hard disk failure is the major cause for crashes, so we removed them from 4801 boxes. 
Otherwise, the boxes are pretty stable and seldom crashes beside our own 
Kernel/drivers bugs. For our traffic monitoring project, all traces are directly 
dumped over NFS to one RAID 0 2 TB storage server.

We have done several things to help us test new software and run experiments 
more conviently. First we install/re-install the kernels and other software 
through a master controller to keep all software synchronized and up-to-date 
automatically. It usually takes 1-2 minutes to re-install everything for all boxes. 
Since the kernel logs are gone after reboot because they are stored in memory 
file systems, we have all kernel logs remotely logged into our master server. 
This helps us to perform post-crash analysis or makes system management easier 
in general. In cases when the kernel hangs/panics or for some reason we can not 
login to perform a manual reboot, we can remotely reboot these boxes 
(and instruct them to boot to a stable kernel) in a minute. In addition, we use 
Geode CPU watch dog functions to make the boxes reboot themselves after certain 
timeout. Thus we minimize manual intervention for software update, experiements, 
and debugging.

[Traceset] ucsd/cse/tcpdump (v. 2008-08-25)

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the initial version.

@MISC{ucsd-cse-tcpdump-2008-08-25,
  author = {Yu-Chung Cheng},
  title = {{CRAWDAD} trace set ucsd/cse/tcpdump (v. 2008-08-25)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/ucsd/cse/tcpdump},
  month = aug,  
  year = 2008
}
					

We collected tcpdump traces of wireless activity in the UCSD Computer Science building.

The tcpdump trace was collected at the gateway router that interfaces 
the campus giga-ether network and the CSE wireless VLAN.

[Trace] ucsd/cse/jigsaw/wireless (v. 2008-08-25)

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the initial version

@MISC{ucsd-cse-jigsaw-wireless-2008-08-25,
  author = {Yu-Chung Cheng},
  title = {{CRAWDAD} trace ucsd/cse/jigsaw/wireless (v. 2008-08-25)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/ucsd/cse/jigsaw/wireless},
  month = aug,  
  year = 2008
}
					

Jigsaw traces of wireless activity in the UCSD Computer Science building.

the (merged) jigsaw traces collected using 192 sniffers in UCSD CSE building.

The file is a series of jcap_hdr ([jcap_hdr.h]) packets like the pcap_pkthdr packet format. 
We created our own header simply to save spaces.

[Trace] ucsd/cse/tcpdump/wired (v. 2008-08-25)

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the initial version

@MISC{ucsd-cse-tcpdump-wired-2008-08-25,
  author = {Yu-Chung Cheng},
  title = {{CRAWDAD} trace ucsd/cse/tcpdump/wired (v. 2008-08-25)}, 
  howpublished = {Downloaded from http://crawdad.cs.dartmouth.edu/ucsd/cse/tcpdump/wired},
  month = aug,  
  year = 2008
}
					

Tcpdump traces of wireless activity in the UCSD Computer Science building.

the tcpdump trace at the gateway router that interfaces the campus giga-ether network and the CSE wireless VLAN.

The format is gzipped tcpdump pcap.

[Author] Yu-Chung Cheng

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[Paper] cheng-cross-layer

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[Paper] cheng-cross-layer-journal

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[Paper] cheng-jigsaw

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