Title: A Survey on Measurement Tools Available For Internet
Author: Asrar Ul Haque
, homepage: http://www.mcs.kent.edu/~ahaque
Prepared for Prof. Javed I. Khan
Department of Computer Science, Kent State University
Date: November 2001
Abstract: The efficient measurement of Internet state has become
an important field to more effectively utilize Internet. In this servey
the available tools and methologies have been explored. With the recents
claims that measurement leads to NP-hard problems and that the existing
tools might give erroneaous results and that the there is need for more
diversified measurements, it is felt that more needs to be done in this
Survey's on Internetwork-based Applications
Back to Javed I. Khan's
Table of Contents:
The explosive growth of Internet has motivated deployment of a great variety
of applications ranging from simple text based application, to multimedia,
IP-telephony and metacomputing services to name a few. This has created
the ever increasing demand for bandwidth, predictable Quality of Service
(QoS), and traffic management. The efficiency of resource allocation and
the quality of service provded by the Internet depends critically on effective
traffic management .
What is to be Measured
Collection and analysis of basic traffic statistics is fundamental to providers'
ability to design and and operate networks and to ensure the QoS for the
time sensitive web applications. In addition to link utilization statistics,
according CAIDA , both long-term aggregated
statistics and short-term per flow statistics provide necessary insights
The sheer volume of the traffic and the high capacity of modern Internet
trunks, however, make traffic monitoring for these and other purposes an
increasingly challenging endeavor.
per-customer accounting, SLA verification
per-peer accounting (traffic balance of trade)
tracking topology and routing changes
tracing back DOS attacks
ATM/cell/circuit level errors
other trouble shooting
TCP flow dynamics
routing table/address space efficiency
Backbone engineering and planning are among the most pressing needs
for reliable forms of traffic data and analyses. Key elements of these
analyses are aggregate traffic data at the IP layer, including port and
protocol statistics (packets and bytes per port and per protocol) and traffic
matrix statistics (how many packets and bytes were sent from network A
to network B).
One participant of ISMA'97 from ANS described what forms of measurement
data that he and other backbone engineers need most, suggesting that critical
data not readily available include:
From the diversified web application point of view, 
argues that emerging tele-interaction applications (such as tele-surgery,
remote instrument control) will require handle on the delay incurred at
the video frame level, which is exactly not the same as the packet delay.
The trend suggests that as more advanced, and complex netcentric applications
are being envisioned more versatile network state information would have
to be exchanged.
Adjacency traps in OSPF
Link Quality Monitoring (LQM) over PPP, ATM, or FDDI
Network prefix and AS Matrices
Length of flows
Statistical traffic samples to trace back things like SYN attacks
The way different properties related to Internet is measured can be classified
into various groups.
Classes of Measurement Approaches
Aggregation-based approaches are deterministic functions of the observed
data  . They usually compute the sum or the maximum
of some metric over the dataset (e.g. sum of packets traversing over a
link during an interval, or the maxiend-to-end round trip delay for a set
Whereas sampling based approaches extract a random subset of all the
possible observations. This sample subset is supposed to be representative
of all of the whole.
Active or direct measurements are network probes developed to measure the
capabilities of the Internet. Active and passive measurements can be compared
to car maintenance . When you are trying to determine
what is wrong with your car, you can either check your car’s oil level
or give your car a test drive. A test drive would be an active measurement
as it changes the state of the vehicle in question, while an oil check
would be a passive measurement, which generally has no effect on the state
of the car. With active measurements, one can generally retrieve additional
information about a network’s capabilities, at the cost of adding interference
and/or injecting probing packets into the network. Conceptually, 
observed that, an passive or indirect measaurement method relies on a network
model and network status information to infer the spatial flow of traffic
through the domain. Some values, like the delays which are dynamic, changing
with the traffic pattern and congestion in the network, may be significantly
affected by the overhead of traffic generated by the protocol that performs
the delay estimation by actively injecting packets into the network; hence,
any such protocol must minimize this traffic overhead 
With explosion of Internet scability of any measuremening tools/architecture
is an important issue.  suggests a hierarchical structure
to achieve scalability. Moreover, both  and 
sends messages to immidiate children nodes to make their architecture scalable.
In this approach, e.g. link measurement, aggregate traffic statistics are
measured on a per-link basis, and are reported periodically. Matrics typically
include number of bytes and packets dropped within a reporting period.
Some of these statistics are defined as part of the SNMP MIBS
.  argued that since some information is lost during
aggregaton and that this appraoch is better suited to detect potential
problems, rather than to actually analyze the problem and modify routing
information to remedy it.
In this approach, e.g. flow aggregation, one or several routers within
the domain collect per-flow measurements. A router has to maintain a cache
of active flows. One disadvantage of flow aggregation is the amount of
measurement data can be considerable and the traffic generated can impose
a significant load on the network.
In this approach, e.g. active end-to-end probes, hosts connected to the
network send probe packets to one or several other hosts to estimate path
metrics, such as the packet loss rate and round trip delay [
8, 9, 10 ].
 shows differents projects which are now underway
targetting different groups.
Comparation of Publicly Accessible Internet Insfrustructure
||Traffic Engr, Internet Researchers
||Network For HEP Community
||High-availability Baclbone For Academic Researchers
||Passive & Active
||Workload & Performance
||Global Internet Comminity, Internet Researchers
|NLANR (MOAT) AMP
|NLANR (MOAT) PMA
|NI ACI NWS
||PACI High_Performance Application Users and Developers
||Active & Passive
||UK Particle Physics Community
||European Internet Comminity
||Global Internet Comminity, Internet Researchers
||US Higher Education Community
||Canadian Particle Physics Community
|U-Oregon Route Views
||Traffic Engr, Internet Researchers
 demonstrated that the problem of collecting link-bandwidth
utilization information from an underlying network while minimizing the
required number of SNMP probes gives rise to a novel, NP-hard generalization
of the traditional Vertex Cover (VC) problem  , termed
Weak VC.  proposed a new, polynomial-time heuristic
algorithm for Weak VC that is provably near-optimal (with a logarithmic
worst-case performance bound). They also showed that the optimal probe
computation problem can be mapped to the well-known Facility Location Problem
(FLP), which allows to use the polynomial-time approximation algorithm
of Hochbaum  to obtain a provably near-optimal set
of IP probes.
 presented network delay estimation protocols that
can be used in multicast environments. Their protocol can be used in unstructured
multicast protocols such as SRM  ; they extend it
into one that can be used in a hierarchical multicast protocols such as
RMTP  . The basic protocol estimates the delay from
each node to every other node in a multicast group during a multicast transmission
session, and applies where there is no logical structure among the receivers
in the session. Receivers do not send any message directly to the sender.
This avoids the implosion problem at the sender. The basic protocol can
be extended to obtain a protocol that estimates the delay from a sender
to every receiver in a hierarchically structured reliable multicast protocol
such as RMTP  , TMTP  , and SHARQFEC
 . A particularly attractive feature of this protocol
is that only receivers that are the immediate children of the sender send
messages directly to it; other receivers do not send any message directly
to the sender. This avoids the implosion problem at the sender.
SPAND (Shared Passive Network PerformanceDiscovery)
is a system that facilitates the development of adaptive network applications.
In each domain, applications make passive application-specific measurements
of the network and store them in a local centralized repository of network
performance information. Other applications may retrieve this information
from the repository and use the shared experiences of all hosts in a domain
to predict future performance. In this way, applications can make informed
decisions about adaptation choices as they communicate with distant hosts.
All messages between the components of SPAND system use a format similar
to Active Messages  . A SPAND message contains a
handler string, an active flag, a data length, and a message-specific payload.
 looked at both of the problems of determining
the setting of the retransmission timer (RTO) for a reliable protocol,
and estimating the bandwidth available to a connection in the context of
TCP, using a large TCP measurement set  for trace-driven
simulations. For RTO estimation, they evaluated a number of different algorithms,
finding that the performance of the estimators is dominated by their minimum
values, and to a lesser extent, the timer granularity, while being virtually
unaffected by how often round-trip time measurements are made or the settings
of the parameters in the exponentially-weighted moving average estimators
commonly used. For bandwidth estimation, they explored techniques previously
sketched in the literature [23, 24] and found that in
practice they perform less well than anticipated. 
developed a receiver-side algorithm that performed significantly better.
Knowledge of the up-to-date bandwidth utilizations and path latencies
is critical for numerous important network management tasks, including
application and user profiling, proactive and reactive resource management
and traffic engineering, as well as providing and verifying QoS guarantees
for end-user applications. Indeed, these observations have led to a recent
flurry of both research and industrial activity in the area of developing
novel tools and infrastructures for measuring network bandwidth and latency
parameters  . Examples include SNMP and RMON measurement
probes  , Cisco’s NetFlow tools 
, the IDMaps  ,  and Network
Distance Maps  efforts for measuring endto-end network
latencies, the pathchar tool for estimating Internet link characteristics
 ,  , and packet-pair algorithms
for measuring link bandwidth  , 
. A crucial requirement for such monitoring tools is that they be deployed
in an intelligent manner in order to avoid placing undue strain on the
shared resources of the production network
Topology-d is a service that estimates the state of
networked resources by periodically computing the end-to-end latency and
available bandwidth. Using its delay and bandwidth estimates, topology-d
computes a fault tolerant, minimum-cost spanning tree connecting participating
TReno meaures the throughput of a given link independent
of the particular TCP implementation on the end host. bprobr and cprobe
probe the network (bandwidth) by sending several pairs (bprobr)
or a short train of packets (cprobr) .
Several projects with measurement infrastructures for monitoring Internet
Traffic are currently in place. These utilize either public or private
infrastructure. CAIDA provides short
summaries of those current measurement projects offering public reports.
CoralReef is a comprehensive software suite providing a set of drivers,
librarie s, utilities, and analysis software for passive network measurement
of workload characteristics. These reports characterize workload on a high-speed
link between UCSD and the commodity Internet.
Internet2 (I2) Abilene is an advanced backbone network that connects
regional network aggregation points, called gigaPoPs, to support the work
of Internet2 universities as they develop advanced Internet applications.
The Abilene Project complements other high-performance research networks.
Abilene enables the testing of advanced network capabilities prior to their
introduction into the application development network. These services are
expected to include Quality of Service (QoS) standards, multicasting and
advanced security and authentication protocols.
IEPM - Internet End-to-end
and Process Monitoring (SLAC/DOE)
SLAC/DOE/ESnet, High Energy and Nuclear Physics uses pingER tools
on 31 monitoring sites to monitor network performance for over 3000 links
in 72 countries. Monitoring includes many major national networks (including
ESNet, vBNS, Internet2-Abilene, CALREN2, NTON, and MREN) as well as networks
in South America, Canada, Europe, the former Soviet Union, New Zealand,
and Africa. Many sites are also part of SLAC's related BaBar
Wide-Area Network Monitoring effort.
MAWI (WIDE Project)
The Measurement and Analysis of Wide-area Internet (MAWI) Working
Group studies performance of networks and networking protocols in Japanese
wide-area networks. Sponsored by the Widely Integrated Distributed Environment
(WIDE) project, MAWI is a joint effort of Japanese network research and
academic institutions with corporate sponsorship.
Private Measurement Infrastructure
with Public Reports
Monitor and Analysis of Traffic in Multicast Routers (Mantra) monitors
various aspects of global Internet multicast behavior at the router level.
Visualization snapshots and accompanying tables are updated every 15-30
NIMI is a project, begun by the National Science Foundation and
currently funded by DARPA, to measure the global Internet. Based on Vern
Paxson's Network Probe Daemon, NIMI was designed to be scalable and dynamic.
NIMI scalability comes from its ability to delegate NIMI probes to administration
managers for configuration and information and measurement coordination.
NIMI is dynamic in that the measurement tools employed are treated as third
party packages that can be added or removed as needed. For example, the
Inference of Network Characteristics) measurement methodology for determinng
performance characteristics of the interior of a network from edge measurements
has been tested and validated using the NIMI infrastructure.
NLANR(MOAT)-AMP Active Measurement
Passive Measurement and Analysis
NLANR's Measurement and Operations Analysis Team (MOAT) is creating
a Network Analysis Infrastructure
(NAI) to derive a better understanding of system service models and
metrics of the Internet. This includes passive measurements based on analysis
of packet header traces (link to PMA above); active measurements (link
to AMP above); SNMP information from participating servers; and Internet
routing related information based on BGP data.
NPACI's Network Weather Service
Distributed system to periodically monitor and dynamically forecast
performance available from various network and computational resources
over a given time interval. Service operates a distributed set of performance
sensors (network monitors, CPU monitors, etc.) from which it gathers readings
of instantaneous conditions. It then uses numerical models to generate
forecasts of what the conditions will be for a given time frame. While
the forecasting methods are general, the focus is on the ability to predict
the TCP/IP end-to-end throughput and latency attainable from applications
using systems located at different sites. Such forecasts are needed both
to support wide-area scheduling of large scale computation, and by the
metacomputing software infrastructure to develop quality-of-service guarantees.
PPNCG Network Monitoring
The PPNCG (Particle Physics Network Coordinating Group) runs network
monitoring processes on machines at several sites throughout Europe. Its
goal is to gather end-to-end performance information for links of specific
interest to particle physics researchers, and use the information to highlight
problems and help the PPNCG to make recommendations to the appropriate
bodies to optimise the networking available to the UK particle physics
community. This project uses Traceping
Route Monitoring Statistics .
RIPE (Reseaux IP Europeens) is a collaborative organisation open
to organisations and individuals,operating wide area IP networks in Europe
and beyond. The objective of RIPE is to ensure the administrative and technical
coordination necessary to enable operation of a pan-European IP network.
RIPE does not operate a network of its own. Currently, more than 1000 organisations
participate in the work. The result of the RIPE coordination effort is
that an individual end-user is presented with a uniform IP service on his
or her desktop irrespective of the particular network his or her workstation
is attached to.
Surveyor : Advanced Network
& Services / Common Solutions Group R&E Network Measurements
Surveyor is a measurement infrastructure that is being currently
deployed at participating sites around the world. Based on standards work
being done in the IETF's IPPM WG, Surveyor measures the performance of
the Internet paths among participating organizations. The project is also
developing methodologies and tools to analyze the performance data.
TRIUMF Network Monitoring
Canadian national research facility uses perl scripts to trace paths
toward nodes of interest to TRIUMF
. Packet los summaries and graphs are generated daily from pins made at
10 minute intervals. Traceroute data is gathered four times daily. Network
vizualization maps are generated from the traceroute data.
University of Oregon's
Route Views Project
A collaborative endeavor to obtain real-time information about the
global routing system from the perspectives of several different backbones
and locations around the Internet. The Route Views router, route-views.oregon-ix.net
, uses multi-hop BGP peering sessions with backbones at interesting locations
(note that location should not matter if the provider is announcing consistent
routes corresponding to its policy). Route Views uses AS65534 in its peering
sessions, and routes received from neighbors are never passed on nor used
to forward traffic. Finally, route-views.oregon-ix.net itself does not
announce any prefixes.
WAND (Waikato Applied
Network Dynamics) WITS (Waikato Internet Traffic Storage) Project
The WAND project aims
to build models of internet traffic for statistical analysis and for the
construction of simulation models. The project builds its own measurement
hardware and collects and archives significant network traces. These are
used internally and are also made available to the Internet research community.
Traces are accurately timestamped and synchronized to GPS. Many traces
are 24 hours long, some are up to a week long, and there are plans to provide
even longer traces in the future. The WAND project is based at the University
of Waikato in New Zealand with strong collaboration from the University
of Auckland .
Andover News Network's Internet
Measures "traffic index", response time, and packet loss by pinging
many routers along "major paths" on the Internet. (traffic index
- a score from 0 to 100 where 0 is "slow" and 100 is "fast", determined
by comparing the current response to a ping echo request with all previous
responses from the same router for past 7 days.)
Business 40 Internet Performance Index
Assessment of average response time for accessing and downloading
home pages of 40 Web Sites deemed most indicative to business users, as
measured Mo nday through Friday every 15 minutes between 6 am and noon
Pacific time by Keyno te software measurement agents located in metropolitan
areas of the United State s. Keynote's methodology
MIDS Internet Average
The MIDS Internet Average is a high-level summary of Internet performance
measured from hosts all around the world. It provides one baseline against
which more specialized Internet performance data might be compared, serving
a similar role as the Dow Jones Industrial Average does in the financial
MIDS Internet Weather Report
The MIDS IWR presents ongoing animated scans of macroscopic conditions
across the Internet. IWR displays geographical maps that show ping-based
RTT latency from MIDS offices in Austin, Texas to thousands of Internet
domains worldwide. Data is currently updated every four hours, six times
a day, seven days a week. Java applets support nonstop viewing and single-stepping
frame by frame. Single GIF images are also available for each of the most
MIDS Matrix IQ Ratings Comparing Performance
of Some ISPs
MIDS monitors thousands of sites worldwide every 15 minutes to map
the data flow of the Internet. Statistical analyses of this data to determine
network performance form the basis for their Matrix Internet Quality (MIQ)
products. Only a small fraction of the information capable of being provided
by MIQ is used in this public ratings page.
for the New Decade
for the New Decade http://www.caida.org/outreach/papers/ieee0001/
As we enter the
new decade, organizations engaged in analyzing macroscopic, infrastructure-wide
traffic behavior  suggests that we must focus on
active measurements that are less invasive and do not provoke providers
to defensive behavior;
passive acquisition of performance data (latency, loss, jitter) that can
reduce the perceived need to actively probe infrastructures;
aggregating, mining, and visualizing the massive data sets in ways that
are useful to multiple users;
mapping IP addresses to more useful analysis entities: autonomous systems
(BGP routing granularity), countries, equipment (multiple IP addresses
map to the same router but without any mechanism to derive the mapping),
and geographic location information (latitude/longitude coordinates);
problems of hardware speed and memory/bus limitations, emerging media (Gigabit
Ethernet, DWDM), IP security, and the reluctance of ISPs to use and/or
share measurement results.
both top-down and bottom-up momentum: users, researchers, and application
developers must scope out the measurements essential to understanding Internet
behavior and growth; ISPs need to deploy and evaluate measurement technology
for their own network design, operation, and cost recovery. This work should
be accompanied by more thoughtful infrastructure-relevant analysis of existing
data. In particular, we need better correlation among data sources and
types and greater feedback into the design of future data acquisition techniques
as well as Internet technologies themselves.
Unlike many other
fields of engineering, Internet data analysis is no longer justifiable
as an isolated activity. The ecosystem under study has grown too large
and is under the auspices of too many independent, uncoordinated entities.
Nonetheless, as the system continues to evolve rapidly, the depth and breadth
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I have extensively searched digital libraries of IEEE and ACM. I have also
searched using search engine (google). I used different combinations search
tags of "internet", "measurement", "congestion", "state" and, "mobile".
I also looked at the sessions related to measurement of INFOCOM of years
2000 and 2001. The papers presented by CAIDA (found from their website)
and their citations were of immense help.