Transcript Introduction

T-110.6120 – Special Course on Data
Communications Software:
Publish/Subscribe Internetworking
Introduction
Arto Karila
Aalto-HIIT
[email protected]
2011-09-12 AK
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ICT and productivity
• It is generally believed that increasing use of ICT is the
most important single tool for increasing productivity
(see e.g. OECD study “ICT and Economic Growth…”)
• Typically deployment of ICT has increased productivity
by 10 to 20 %, especially when processed have been
revised at the same time
• With mobile solutions even 40% increases have been
achieved
• Experience from developing countries shows that ICT
can boost productivity there at least as much as in
developed countries
• We are still probably utilizing less than 10% of the
opportunities of ICT
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Opportunities of ICT…
ICT can be utilized a lot more in all areas of life:
• Public sector:
– Health and elderly care
– Education
– All public services
– True openness and direct participation
• Enterprises:
– Logistics, ERP, CRM, groupware, …
– Mobile access to business-critical systems
– Networking with partners, customers, and others
– Integration of voice and video
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… Opportunities of ICT
• Private life:
– Social media
– Entertainment (TV, music, gaming etc.)
– Secure and mobile access to public and private
services:
•
•
•
•
Health, social services, taxes etc.
Education
Banking
etc.
All this requires a lot from
the underlying network!
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Computer networking
• Computer networking was developed for mainframes
(on the left ENIAC and on the right IBM S/360)
• Sharing devices: computers, mass memory, printers etc.
which have addresses
• Traffic is point-to-point
between two devices
or network interfaces
• The old paradigm still
lives even though the
world around has
completely changed
• Something has to be
done about this
Picture source: IDG News Service
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History of the Internet…
1957: Advanced Research Projects Agency (ARPA)
was founded after the launch of the Soviet
satellite Sputnik
1968: ARPA started the development of the
ARPANET
1969: The first four nodes of the ARPANET were
connected (the first message: ”lo”)
1974: Robert Kahn and Vinton Cerf defined the basic
Internet architecture (TCP/IP)
1975: DARPA started the development of Internet
technology
1983: On 1/1/1983 the ARPANET was converted to TCP/IP
BSD 4.2 had TCP/IP protocol stack
1988: FUNET joined the Internet
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… History of the Internet
1989: Telecom Finland published DataNet
BGP-1 was defined
1990: NSFNET was founded
1991: The first World Wide Web (WWW) client Mosaic
was published at CERN
1993: CIDR and BGP-4 were adopted
1990’s: The Internet secured its position as the leading
network architecture
2000: The number of Internet hosts exceeded
100,000,000
2011: The number of Internet hosts is approaching
1 billion (1000,000,000)
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Growth of the Internet
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Problems with the current Internet
• Over the past 30 years, several major changes have
been made to the Internet – always at the last moment
• Internet’s success is largely based on its ability to
adapt to the changing requirements
• With these changes, the end-to-end principle is already
destroyed by middle-boxes (NAT and firewalls)
• We have reached a point, where the Internet is ossified
and new transport protocols are virtually impossible
• The Internet should be able to accommodate a wider
range of tussles
• We need a clear separation of the naming space and
network functions
• The Internet is working on the terms of the sender
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Why the Internet only just works
• See: Why the Internet only just works, M. Handley,
BT Technology Journal, Vol 24 No 3, July 2006
• Throughout its life, the Internet has only just worked
and all of the major changes have been made at the
last possible time
• CIDR and NAT were introduced because of the
exhaustion of the IPv4 address space
• These were supposed to be temporary solutions,
waiting for IPv6 to break through, but they have
become permanent
• At the same time firewalls proliferated
• The end-to-end principle of the Internet no longer
works because of the middle boxes (firewalls and NAT)
• This has lead to it being virtually impossible to make
any changes to the transport layer (TCP/UDP)
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Ossification of the Internet
• We have ended up in a vicious circle:
– Developers cannot use a new protocol because it
cannot traverse firewalls and NAT
– It is not worth while for the developers of firewalls
and NAT to change the middle boxes because there
are no users of new transport protocols
• No major changes have been made to the core
protocols of the Internet since 1993
• The core protocols of the Internet are ossified while
the needs have developed significantly
• Innovation in the Internet is withering
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Security and Trust
• Junk mail (Spam) and other types of unsolicited traffic
are growing problems
• There still are no effective defense strategies against
Distributed Denial of Service (DDoS) attacks
• Worms, viruses, Trojan horses, spyware, and other
malware is spreading fast throughout the Internet
• Phishing is a growing problem
• The Internet was developed for a community where
everybody was assumed trustworthy – now trust in the
Internet has eroded
• Now that the Internet is used by everybody, we need to
enable communication between distrusting parties
• We need mechanisms by which people and companies
can build and evaluate trust
• Combining privacy and reputation is challenging
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Some challenges of the Internet
• Among the well understood requirements for the
Internet are the following:
– Multicast
– Mobility
– Multi-homing
– Security
– Quality of Service (QoS)
– Ability to handle massive video (including IPTV)
– Scalability to future needs (Network of Things etc.)
• Solutions to many of the needs listed above have been
developed but not widely deployed
• Operators don’t have incentives to bring new features
to the market because they are only useful if they are
interoperable with other operators, in which case they
give no competitive advantage
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IPv6
• IPv6 was defined in 1995 and expected to spread fast
• It is still hardly used in Western countries
• The main improvement of IPv6 is moving from 32-bit to
128-bit addresses
• IPv6 was defined at a time when nobody could foresee
all of the uses and needs of the Internet that we have
now
• CIDR and NAT have eased the shortage of IPv4
addresses but now they are really running out
• The transition to IPv6 will be a long one and it won’t
solve most of the problems
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Expensive transit
• The current inter-operator routing protocol BGP-4
does not fulfill modern requirements but there is
no successor to it in sight
• Tier-1 operators (AT&T, MCI, Sprint, C&W etc.) are a
group of about a dozen global operators with mutual
peering agreements
• Tier-1 operators don’t pay for transit while others pay
to them (tier-2 operators directly and others indirectly)
• In Practice they form a cartel, which wants to cement
the market and is not advocating development
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Storage vs. Transit Price
2009
$100/MB
$10/MB
$1/MB
$100/GB
$10/GB
$1/GB
$0.1/GB
1985
1990
1995
2000
2005
2010
Source: Dr. Pekka Nikander
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Microeconomics
•
•
•
•
•
Over the past decade, microeconomics have grown in
importance
We need economic mechanisms that encourage
people to do good for the community
The Internet was developed with public funds for
research and education without any commercial
considerations
If we want to inject resources into the network, it
must be possible for the party paying for them to also
receive (some of) the revenues
We need to create ways for companies and people to
improve their own economies by doing things
beneficial for the community
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Users – Applications – Data
• Users, applications and data are involved in computing
• All three are becoming increasingly mobile
• The network has to bring these three together in a
reliable, secure and efficient way
Users
Network
Appl.
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Clouds and Grids
• Applications are increasingly run in cloud and grid
environments
• Cloud computing was created to cut down the cost and
increase the flexibility of computing
• In a cloud, dynamically scalable and often virtualized
ICT resources are offered as services over the Internet
• Google started packing cheap off-the-shelf computers
and DC UPS’s into containers and placing them everywhere, cutting the cost of data centers by a factor of 10
• While clouds still are based on computing centers,
grids can run in millions of PCs
• With ever more powerful portable devices and the
proliferation of mobile data, also grids will be
increasingly mobile
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Scalability
• The Internet has already scaled to a level that was
unconceivable to its original developers
• However, new trends will raise the scalability
requirement of the Internet to a much higher level:
– Proliferation of video (YouTube, IPTV etc.)
– Ubiquitous computing (ubicomp)
– Sensor networks
– Internet of things
• The amount of video traffic is growing rapidly in
wireline and wireless networks
• We have to be ready for dozens and hundreds of
billions of nodes in the network in the near future
• The capacities and abilities of nodes will vary highly
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About applications
• Most applications are still generic in nature and
basically the same as in the 1980’s (e.g. office suites)
• On the other hand, ERP systems (such as SAP) tend to
cement the existing flawed processes
• We should be developing applications that directly
support work flows thereby increasing productivity
• With modern tools (e.g. AJAX and QT) and methods
(e.g. agile programming) we should be able to cut
down the development time and cost by a factor of 10
• Middleware is getting standardized and applications
becoming component-based, easing integration
• Applications are dealing with information, which is
structured and linked
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Requirements
• The network has to meet the needs of the applications
of today and the future:
– Mobility of users, data and computation
– Scalability up to hundreds of billions of nodes
– Efficient handling of video
– In-built security, including protection against SPAM
and DoS attacks
• We are interested in information content – not who is
storing it and where
• Network has to support access to and processing of
large amounts of hierarchically organized information
• There needs to be a simple, powerful and efficient API
for accessing the services of the network – the API
could be generic and run on different networks
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Conclusions
• There is a growing consensus among researchers of
internetworking that a fundamental reform is needed
• We need to be able to name and address information
rather than hosts or interfaces
• We need mechanisms for structuring information and
limiting its visibility
• We need to have a way to store information graphs in
the network and retrieve and process them in an
efficient way, not caring about their whereabouts
• Information Centric Networking (ICN) and, more
specifically, the Publish/Subscribe (pub/sub) paradigm
seem to offer solutions to our needs
• PSIRP/PURSUIT is an attempt to that direction
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