Ankit Singla
University of Illinois
Bala Chandrasekaran
Brighten Godfrey
Duke University
University of Illinois
Nadi Bozkurt
Greg Laughlin
Anthony Aguirre
Duke University
UC Santa Cruz
UC Santa Cruz
The Speed of Light Manifesto:
The Internet should operate at the speed of light.
“How long until our pigeon system rivals those of
the continental powers?”
– The Nineteenth Century (British Periodical), 1899
[telegeography.com]
A toy experiment
$ wget theoatmeal.com
• 430ms (fetch size 20KB)
$ ping 208.70.160.53
• 55ms
Urbana-Portland roundtrip distance
• 5700 kilometers
• 19ms at the speed of light in vacuum
23x inflation over c-latency!
Time to fetch Alexa top 500 HTML
CDF
Inflation over c-latency
Time to fetch Alexa top 500 HTML
CDF
34x
Inflation over c-latency
0.1s ~ 1% revenue
A speed-of-light Internet would enable
“tele-interaction”
Remote collaboration and games
Tele-surgery with haptic feedback
The new and unexpected
11
Hit it!!
A speed-of-light Internet would provide
“Instant” Access
A screen change occurring within 30ms of
clicking a button appears instantaneous.
13
30ms
[Wikipedia user Toffelginkgo]
latency
radius
Community size
A speed of light Internet would provide
super-linear growth in community size
c
2
c
20
49x
Latency radius
Number of people within 30ms of 200 world capitol cities.
16
Benefit
Population reachable (in
billions)
Latency and community size
Super-linear growth
Communication
speed
Research
progress
Why are we so
far from the
speed of light?
[comcast.com]
[verizon.com]
[speedtest.net]
Latency inflation breakdown
CDF
Inflation over c-latency to the Web server
Latency inflation breakdown
DNS
CDF
5.4x
Inflation over c-latency to the Web server
Latency inflation breakdown
Router-path
DNS
CDF
2.3x
Inflation over c-latency to the Web server
1
2
3
4
Latency inflation breakdown
Router-path
Min ping
DNS
CDF
3.2x
Inflation over c-latency to the Web server
Router path vs. ping
Inflation in fiber distances
Ground truth data on fiber lengths!
Inflation in fiber distances
CDF
Inflation over geo-distance
Inflation in fiber distances
Road
CDF
Inflation over geo-distance
Inflation in fiber distances
Road
Fiber
CDF
Inflation over geo-distance
Inflation in fiber distances
Road
Road
Fiber
GÉANT
CDF
CDF
Fiber
Internet 2
Inflation over geo-distance
Road
Fiber
Inflation over geo-distance
CDF
ESnet*
Inflation over geo-distance
* Dhruv Diddi (UIUC) helped process ESnet data
Latency inflation breakdown
Router-path
Min ping
TCP handshake
DNS
CDF
3.2x
Inflation over c-latency to the Web server
Latency inflation breakdown
Router-path
Min ping
TCP handshake
DNS
TCP transfer
CDF
8.7x
Inflation over c-latency to the Web server
Latency inflation breakdown
Router-path
Min ping
TCP handshake
DNS
TCP transfer
Total time
CDF
24.6x
Inflation over c-latency
Latency inflation breakdown
Total time
(24.6x)
=
DNS resolution (5.4x)
+
TCP handshake (3.2x)
+
TCP transfer (8.7x)
Latency inflation breakdown
Total time
(24.6x)
=
DNS resolution (5.4x)
+
TCP handshake (3.2x)
+
Request (3.2x)
+
TCP transfer (8.7x)
Inflation at lower layers affects
everything!
Absent inflation in the lower layers …
Total time
(24.6x)
8.2x
=
1.7x
DNS resolution (5.4x)
+
1x
TCP handshake (3.2x)
+
1x
Request (3.2x)
+
2.7x
TCP transfer (8.7x)
(Normalized by the 3.2x inflation in minimum ping
time)
Could we build
a speed-of-light
Internet?
Conduit Map
(Durairajan, Barford, Sommers, Willinger)
Stretch
(gravity model, all pairs of cities, pop. > 20K)
# of cities: 249
Mean : 1.2349
Min = 1
Max = 9.3335
Median : 1.1967
Std : 0.1987
90% : 1.4118
95% : 1.5403
[wired.com]
•
•
•
•
•
2526 towers from FCC database connecting 300 city pairs
Median stretch 1.08, 90th percentile stretch 1.15
400Mbps links, 70km maximum range
Enough capacity to carry 1% of non-video traffic in U.S.
Approximate cost: $250M up front, plus $100M per year
More detailed map (Anthony Aguirre and Greg Laughlin)
Operating a c-ISP
Bundle with traditional Internet service offering.
Provide tools for directing traffic for interactive applications
over the low latency network.
Within the network,
• Deploy ubiquitous DNS replication
Across the network,
• Employ “cold potato” routing – route each packet as
close to its destination as possible
At the edge of the network,
• Proxies terminate connections originating in the network
Future work…