On CommunityOriented Internet Measurement

1
On Community-Oriented Internet Measurement

• Mark Allman
• ICSI
• Lann Martin, Michael Rabinovich
• EECS Dept., CWRU
• Kenneth Atchinson
• Baldwin-Wallace College

2
Internet Measurements

• A great need
• Never-ending
• Active community
• High barrier of entry into the field
• Requires deep expertise
• Needs professional contacts
• Involves significant effort
• A frequent result
• General inferences from small-scale studies

3
Existing Infrastructures

• Research infrastructures
• IDMaps, NIMI, Skitter, Ark, RouteView,
• Lots of functionality for large maintenance costs
• Commercial platforms
• Keynote, Gomez
• P2P platforms
• DipZoom
• Still the core to maintain
• GIGRIB
• User-based platforms
• NetDimes, traceroute_at_home
• Specific experiments, not general measurement
  enablers

4
OpenMeas

• Remove dedicated infrastructure
• No dedicated infrastructure!
• All functionality at the end-hosts
• An existing DHT as the glue
• Benefits
• Nothing to maintain
• Community orientation
• Lowering the barrier of entry to the
  measurements studies
• But limited functionality
• No find-grained time coordination
• Best effort

DHT
5
Architecture Overview

• Requirements for DHT
• Get/put interface
• Put(key, value, ttl)
• Get(key)
• OpenDHT fits the bill
• Measurement requesters
• Deposit requests
• Poll for results
• Measurement providers
• Poll for requests
• Deposit results
• Watchers (in particular long-term data
  repositories)
• Poll for results

6
Main Tasks

• Identifying MPs to request measurements from
• Requesting measurements
• Processing measurements and reporting results
• Retrieving requested measurements
• Retrieving watched measurements

7
Identifying MPs
AllMPs
Extra info
MeasType
ltMPRespQueuegt
ltMPReqQueuegt
ltMPReqQueuegt
ltMPRespQueuegt
Extra request attributes
StartTime
ltRespQueueKeygt
Req-string
MPID
ltMeasUIDgt
ltRespQueuegt
MPID
ltMeasUIDgt
ltMeasUIDgt
MPID
MeasurementResults

• MP registration (done by MP)
• Put(AllMP, ping-0.45b reqQ5 respQ5
  extra-info)
• Finding an MP (done by client - requester or
  watcher)
• Get(AllMPs)
• Select MPs, i.e., (ltMPReqQueuegt, ltMPRespQueuegt)

8
Requesting Measurements
AllMPs
Extra info
MeasType
ltMPRespQueuegt
ltMPReqQueuegt
ltMPReqQueuegt
ltMPRespQueuegt
Extra request attributes
StartTime
ltRespQueueKeygt
Req-string
MPID
ltMeasUIDgt
ltRespQueuegt
MPID
ltMeasUIDgt
ltMeasUIDgt
MPID
MeasurementResults

• Create a request record for selected MP (done by
  requester)
• Put(reqQ5, 184866301 clientResults_31 -c 100
  www.icir.org)

9
Processing Measurements (done by MP)
AllMPs
Extra info
MeasType
ltMPRespQueuegt
ltMPReqQueuegt
ltMPReqQueuegt
ltMPRespQueuegt
Extra request attributes
StartTime
ltRespQueueKeygt
Req-string
MPID
ltMeasUIDgt
ltRespQueuegt
MPID
ltMeasUIDgt
ltMeasUIDgt
MPID
MeasurementResults

• Retrieving requests
• Get(reqQ5)
• Identifying new requests in table reqQ5
• Generating a unique measurement ID U
• Putting results into DHT
• Put(U, result)
• Put(respQ5, U)
• Put(clientResults_135, U)

10
Retrieving Results
AllMPs
Extra info
MeasType
ltMPRespQueuegt
ltMPReqQueuegt
ltMPReqQueuegt
ltMPRespQueuegt
Extra request attributes
StartTime
ltRespQueueKeygt
Req-string
MPID
ltMeasUIDgt
ltRespQueuegt
MPID
ltMeasUIDgt
ltMeasUIDgt
MPID
MeasurementResults
By requester
By watcher

• Periodically retrieve own results table
• Get(clientResults_135)
• Identify new result UIDs
• Retrieve results
• Get(U)

• Similar but with resQ5 table.

11
Security

• Threats
• DoS against an MP
• Reflected DoS against measurement target
• Attacker identity laundering
• Mitigation
• MPs best-effort processing
• In particular, rate limiting
• Protects against MP-targeted DoS
• Measurement target-keyed DHT tables recording
  measurement rate
• Protects against a reflected DoS attack
• Community orientation
• Building web-of-trust of requesters
• Crypto-signing measurement requests
• Honoring requests from requesters with proper
  web-of-trust credentials

12
Primitives

• MP Registration
• Removing duplicates from DHT tables
• Fragmentation and reassembly of data due to DHT
  table size limitations
• Assessing trust
• Etc.

13
Summary

• We propose a new measurement platform
• Open
• Community-oriented
• Light-weight - infrastructure-less!
• Utilizes an existing substrate (DHT)
• Incrementally growing (or shrinking)
• We built a small prototype
• Provides a generic client
• An MP offering traceroutes