Broad and load-aware anycast mapping with verfploeter and load-aware... · Before calibration After...
Transcript of Broad and load-aware anycast mapping with verfploeter and load-aware... · Before calibration After...
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BROAD AND LOAD-AWARE ANYCAST MAPPING WITH VERFPLOETER
WOUTER B. DE VRIES, RICARDO DE O. SCHMIDT, WES HARDAKER,
JOHN HEIDEMANN, PIETER-TJERK DE BOER AND AIKO PRAS
London - November 3, 2017
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INTRODUCTION
Anycast site
User
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INTRODUCTION
Users are routed to a
(potentially) nearby site
Anycast site
User
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INTRODUCTION
Users are routed to a
(potentially) nearby site
The set of clients that reach a site
define that sites catchment
Anycast site
User
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INTRODUCTION
Users are routed to a
(potentially) nearby site
The set of clients that reach a site
define that sites catchment
Catchments are often messy and not divided
into neat geographic areas
Anycast site
User
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Peering agreements, Transits and BGP policies influence the routing process.
You don’t know where a client from a certain prefix will be routed until he is routed there.
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INTRODUCTION
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Peering agreements, Transits and BGP policies influence the routing process.
You don’t know where a client from a certain prefix will be routed until he is routed there.
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INTRODUCTION
Suboptimal routing can lead to severely
degraded performance, in terms of RTT,
load balancing and resilience
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DETERMINING CATCHMENT - TODAY
• Analyze log files
• Only if you have them
• Use active probing (e.g. RIPE Atlas)
• Requires VPs at many locations
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DETERMINING CATCHMENT - TODAY
• Analyze log files
• Only if you have them
• Use active probing (e.g. RIPE Atlas)
• Requires VPs at many locations
NL: 563 VPs
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DETERMINING CATCHMENT - TODAY
• Analyze log files
• Only if you have them
• Use active probing (e.g. RIPE Atlas)
• Requires VPs at many locations
NL: 563 VPs China: 19 VPsBrazil: 63 VPs
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• Develop a method to accurately map anycastcatchments
• Without requiring input from users
• “Calibrate” the anycast catchment to the actual client base of the service
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GOALS
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VERFPLOETER: METHODOLOGYACTIVE MEASUREMENT WITH “PASSIVE” VANTAGE POINTS
Anycast sites
Vantage points
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VERFPLOETER: METHODOLOGYACTIVE MEASUREMENT WITH “PASSIVE” VANTAGE POINTS
Send out ICMP Echo Requests
Anycast sites
Vantage points
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VERFPLOETER: METHODOLOGYACTIVE MEASUREMENT WITH “PASSIVE” VANTAGE POINTS
Anycast sites
Vantage points
ICMP Echo Replies are
routed towards “nearest”
anycast site
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VERFPLOETER: METHODOLOGYACTIVE MEASUREMENT WITH “PASSIVE” VANTAGE POINTS
Anycast sites
Vantage points
This defines the
catchment that each
VP belongs to
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ICMP-responding IPv4 or IPv6 addresses
We use a recent IPv4 hitlist from USC/ISI:
https://ant.isi.edu/datasets/ip_hitlists/
1 IPv4 address per /24 block: 14.7 million addresses
6.3 million after removing those in which there was never a responding host
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WHAT ARE THE PASSIVE VPS
1.0.0.0/24 – 1.0.0.571.0.1.0/24 – 1.0.1.851.0.2.0/24 – 1.0.2.41.0.3.0/24 – 1.0.3.204
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• The B Root DNS
• Anycast since 1st of May 2017
• 2 anycast sites
• Our anycast testbed
• 9 anycast sites
Measured catchment using both Atlas and Verfploeter
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USING VERFPLOETER: TWO CASE STUDIES
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FROM ATLAS TO VERFPLOETERB-ROOT CASE STUDY
Atlas Verfploeter
/24 blocks seen 8,677 (of 9083) 3,786,907 (of 6,877,175)
Geolocatable 8,677 3,786,229
Unique 2,079 3,606,300
Geolocated using
MaxMind GeoLite2
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FROM ATLAS TO VERFPLOETERB-ROOT CASE STUDY
Note scale
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FROM ATLAS TO VERFPLOETERB-ROOT CASE STUDY
Note scaleEach “dot” is
a pie chart
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Note scale
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FROM ATLAS TO VERFPLOETERB-ROOT CASE STUDY
Atlas scale
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Note scale
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FROM ATLAS TO VERFPLOETERB-ROOT CASE STUDY
Atlas Verfploeter
Atlas scale
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Note scale
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FROM ATLAS TO VERFPLOETERB-ROOT CASE STUDY
Atlas Verfploeter
Atlas scale
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Note scale
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FROM ATLAS TO VERFPLOETERB-ROOT CASE STUDY
Atlas Verfploeter
Atlas scale
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A more diverse ground for verfploeter measurements:
Our 9-site anycast testbed
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MEASURING AN ANYCAST TESTBED: TANGLED
Location Host Upstream
AU Sydney Vultr AS20473
FR Paris Vultr AS20473
JP Tokyo WIDE AS2500
NL Enschede Univ. of Twente AS1103
UK London Vultr AS20473
US Washington USC/ISI AS1972
US Miami Florida Int. Univ. AS20080
BR Sao Paulo Florida Int. Univ. AS1251
DK Copenhagen DK-Hostmaster AS39389
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A more diverse ground for verfploeter measurements:
Our 9-site anycast testbed
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MEASURING AN ANYCAST TESTBED: TANGLED
Location Host Upstream
AU Sydney Vultr AS20473
FR Paris Vultr AS20473
JP Tokyo WIDE AS2500
NL Enschede Univ. of Twente AS1103
UK London Vultr AS20473
US Washington USC/ISI AS1972
US Miami Florida Int. Univ. AS20080
BR Sao Paulo Florida Int. Univ. AS1251
DK Copenhagen DK-Hostmaster AS39389
Location Host Upstream
AU Sydney Vultr AS20473
FR Paris Vultr AS20473
JP Tokyo WIDE AS2500
NL Enschede Univ. of Twente AS1103
UK London Vultr AS20473
US Washington USC/ISI AS1972
US Miami Florida Int. Univ. AS20080
BR Sao Paulo Florida Int. Univ. AS1251
DK Copenhagen DK-Hostmaster AS39389
Shared upstream
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MEASURING AN ANYCAST TESTBED: TANGLEDATLAS VS VERFPLOETER
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MEASURING AN ANYCAST TESTBED: TANGLEDATLAS VS VERFPLOETER
Atlas Verfploeter
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MEASURING AN ANYCAST TESTBED: TANGLEDATLAS VS VERFPLOETER
Atlas Verfploeter
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Not all measured prefixes are equal
Some will send no traffic, others a lot
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CALIBRATING CATCHMENT
e.g. due to NAT or ISP DNS Forwarders
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Prefix Site
1.0.0.0/24 LAX
1.0.1.0/24 LAX
1.0.2.0/24 LAX
1.0.3.0/24 MIA
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CALIBRATING CATCHMENT
Prefix Load
1.0.0.0/24 10 Q/s
1.0.1.0/24 0 Q/s
1.0.2.0/24 0 Q/s
1.0.3.0/24 15 Q/s
RIGHT
JOIN
Obtained with Verfploeter
Obtained from (historic)
log files or from
a service with a similar
user base
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CALIBRATING CATCHMENT
Prefix Site
1.0.0.0/24 LAX
1.0.1.0/24 LAX
1.0.2.0/24 LAX
1.0.3.0/24 MIA
Prefix Load
1.0.0.0/24 10 Q/s
1.0.1.0/24 0 Q/s
1.0.2.0/24 0 Q/s
1.0.3.0/24 15 Q/s
Prefix Site Load
1.0.0.0/24 LAX 10 Q/s
1.0.1.0/24 LAX 0 Q/s
1.0.2.0/24 LAX 0 Q/s
1.0.3.0/24 MIA 15 Q/s
RIGHT
JOIN
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CALIBRATING CATCHMENT
Prefix Site
1.0.0.0/24 LAX
1.0.1.0/24 LAX
1.0.2.0/24 LAX
1.0.3.0/24 MIA
Prefix Load
1.0.0.0/24 10 Q/s
1.0.1.0/24 0 Q/s
1.0.2.0/24 0 Q/s
1.0.3.0/24 15 Q/s
Prefix Site Load
1.0.0.0/24 LAX 10 Q/s
1.0.1.0/24 LAX 0 Q/s
1.0.2.0/24 LAX 0 Q/s
1.0.3.0/24 MIA 15 Q/s
RIGHT
JOINSITE Fraction of traffic
LAX 0.40
MIA 0.60
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1. Record traffic from unicast B-root (prior to anycast deployment)
2. Run Verfploeter on anycast B-root
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CALIBRATING CATCHMENT AT B-ROOT
Date Site Queries/day Queries/sec
2017-04-12 LAX (Unicast) 2.34G 27.1k
2017-05-15 Both 2.20G 25.4k
LAX 1.78G 20.6k
MIA 0.407G 4.71k
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Date Method Measurement % to LAX
May 15th RIPE Atlas 9682 VPs 82.4%
May 15th Verfploeter 3.923M /24s 87.8%
May 15th Verfploeter x Load 81.6%
May 15th Actual load 2.188G q/day 81.4%
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CALIBRATING CATCHMENT AT B-ROOTRECORDED TRAFFIC COMBINED WITH VERFPLOETER
Before
calibration
After
calibration
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CALIBRATING CATCHMENT AT B-ROOT
Verfploeter allows you to experiment
with various configurations and how
that affects the load on the sites of
your service
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INSIDE AUTONOMOUS SYSTEMS
Anycast site
User
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INSIDE AUTONOMOUS SYSTEMS
Is one vantage point per AS enough?
Anycast site
User
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INSIDE AUTONOMOUS SYSTEMSNUMBER OF SITES VERSUS NUMBER OF ANNOUNCED PREFIXES
We see more than 1 site from
around 12.7% of all ASes
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CONCLUSIONS
• Verfploeter has ~430x more “vantage points” than Atlas
• Atlas has some blocks that we don’t have
• Calibration of measured catchment to actual user base is required
Improve your anycasted service using Verfploeter
https://github.com/woutifier/
Do your own analysis with our public datasets
https://ant.isi.edu/datasets/anycast/index.html#verfploeter
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QUESTIONS AND COMMENTS
22
London - November 3, 2017