Request for Comments: 3869 S. Floyd, Ed.
Category: Informational Internet Architecture Board
August 2004
IAB Concerns and Recommendations
Regarding Internet Research and Evolution
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2004).
Abstract
This document discusses IAB concerns that ongoing research is needed
to further the evolution of the Internet infrastructure, and that
consistent, sufficient non-commercial funding is needed to enable
such research.
Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 2
1.1. Document Organization. . . . . . . . . . . . . . . . . . 2
1.2. IAB Concerns . . . . . . . . . . . . . . . . . . . . . . 3
1.3. Contributions to this Document . . . . . . . . . . . . . 4
2. History of Internet Research and Research Funding. . . . . . . 4
2.1. Prior to 1980. . . . . . . . . . . . . . . . . . . . . . 4
2.2. 1980s and early 1990s. . . . . . . . . . . . . . . . . . 5
2.3. Mid-1990s to 2003. . . . . . . . . . . . . . . . . . . . 6
2.4. Current Status . . . . . . . . . . . . . . . . . . . . . 6
3. Open Internet Research Topics. . . . . . . . . . . . . . . . . 7
3.1. Scope and Limitations. . . . . . . . . . . . . . . . . . 7
3.2. Naming . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.2.1. Domain Name System (DNS). . . . . . . . . . . . 8
3.2.2. New Namespaces. . . . . . . . . . . . . . . . . 9
3.3. Routing. . . . . . . . . . . . . . . . . . . . . . . . . 9
3.3.1. Inter-domain Routing. . . . . . . . . . . . . . 10
3.3.2. Routing Integrity . . . . . . . . . . . . . . . 11
3.3.3. Routing Algorithms. . . . . . . . . . . . . . . 12
3.3.4. Mobile and Ad-Hoc Routing . . . . . . . . . . . 13
3.4. Security . . . . . . . . . . . . . . . . . . . . . . . . 13
3.4.1. Formal Methods. . . . . . . . . . . . . . . . . 14
3.4.2. Key Management. . . . . . . . . . . . . . . . . 14
3.4.3. Cryptography. . . . . . . . . . . . . . . . . . 15
3.4.4. Security for Distributed Computing. . . . . . . 15
3.4.5. Deployment Considerations in Security . . . . . 15
3.4.6. Denial of Service Protection. . . . . . . . . . 16
3.5. Network Management . . . . . . . . . . . . . . . . . . . 16
3.5.1. Managing Networks, Not Devices. . . . . . . . . 16
3.5.2. Enhanced Monitoring Capabilities. . . . . . . . 17
3.5.3. Customer Network Management . . . . . . . . . . 17
3.5.4. Autonomous Network Management . . . . . . . . . 17
3.6. Quality of Service . . . . . . . . . . . . . . . . . . . 17
3.6.1. Inter-Domain QoS Architecture . . . . . . . . . 18
3.6.2. New Queuing Disciplines . . . . . . . . . . . . 19
3.7. Congestion Control . . . . . . . . . . . . . . . . . . . 19
3.8. Studying the Evolution of the Internet Infrastructure. . 20
3.9. Middleboxes. . . . . . . . . . . . . . . . . . . . . . . 21
3.10. Internet Measurement . . . . . . . . . . . . . . . . . . 21
3.11. Applications . . . . . . . . . . . . . . . . . . . . . . 22
3.12. Meeting the Needs of the Future. . . . . . . . . . . . . 22
3.13. Freely Distributable Prototypes. . . . . . . . . . . . . 23
4. Conclusions. . . . . . . . . . . . . . . . . . . . . . . . . . 23
5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 23
6. Security Considerations. . . . . . . . . . . . . . . . . . . . 24
7. Informative References . . . . . . . . . . . . . . . . . . . . 24
8. Authors’ Addresses . . . . . . . . . . . . . . . . . . . . . . 29
9. Full Copyright Statement . . . . . . . . . . . . . . . . . . . 30
1. Introduction
This document discusses the history of funding for Internet research,
expresses concern about the current state of such funding, and
outlines several specific areas that the IAB believes merit
additional research. Current funding levels for Internet research
are not generally adequate, and several important research areas are
significantly underfunded. This situation needs to be rectified for
the Internet to continue its evolution and development.
1.1. Document Organization
The first part of the document is a high-level discussion of the
history of funding for Internet research to provide some historical
context to this document. The early funding of Internet research was
largely from the U.S. government, followed by a period in the second
half of the 1990s of commercial funding and of funding from several
governments. However, the commercial funding for Internet research
has been reduced due to the recent economic downturn.
The second part of the document provides an incomplete set of open
Internet research topics. These are only examples, intended to
illustrate the breadth of open research topics. This second section
supports the general thesis that ongoing research is needed to
further the evolution of the Internet infrastructure. This includes
research on the medium-time-scale evolution of the Internet
infrastructure as well as research on longer-time-scale grand
challenges. This also includes many research issues that are already
being actively investigated in the Internet research community.
Areas that are discussed in this section include the following:
naming, routing, security, network management, and transport. Issues
that require more research also include more general architectural
issues such as layering and communication between layers. In
addition, general topics discussed in this section include modeling,
measurement, simulation, test-beds, etc. We are focusing on topics
that are related to the IETF and IRTF (Internet Research Task Force)
agendas. (For example, Grid issues are not discussed in this
document because they are addressed through the Global Grid Forum and
other Grid-specific organizations, not in the IETF.)
Where possible, the examples in this document point to separate
documents on these issues, and only give a high-level summary of the
issues raised in those documents.
1.2. IAB Concerns
In the aftermath of September 11 2001, there seems to be a renewed
interest by governments in funding research for Internet-related
security issues. From [Jackson02]: "It is generally agreed that the
security and reliability of the basic protocols underlying the
Internet have not received enough attention because no one has a
proprietary interest in them".
That quote brings out a key issue in funding for Internet research,
which is that because no single organization (e.g., no single
government, software company, equipment vendor, or network operator)
has a sense of ownership of the global Internet infrastructure,
research on the general issues of the Internet infrastructure are
often not adequately funded. In our current challenging economic
climate, it is not surprising that commercial funding sources are
more likely to fund that research that leads to a direct competitive
advantage.
The principal thesis of this document is that if commercial funding
is the main source of funding for future Internet research, the
future of the Internet infrastructure could be in trouble. In
addition to issues about which projects are funded, the funding
source can also affect the content of the research, for example,
towards or against the development of open standards, or taking
varying degrees of care about the effect of the developed protocols
on the other traffic on the Internet.
At the same time, many significant research contributions in
networking have come from commercial funding. However, for most of
the topics in this document, relying solely on commercially-funded
research would not be adequate. Much of today’s commercial funding
is focused on technology transition, taking results from non-
commercial research and putting them into shipping commercial
products. We have not tried to delve into each of the research
issues below to discuss, for each issue, what are the potentials and
limitations of commercial funding for research in that area.
On a more practical note, if there was no commercial funding for
Internet research, then few research projects would be taken to
completion with implementations, deployment, and follow-up
evaluation.
While it is theoretically possible for there to be too much funding
for Internet research, that is far from the current problem. There
is also much that could be done within the network research community
to make Internet research more focused and productive, but that would
belong in a separate document.
1.3. Contributions to this Document
A number of people have directly contributed text for this document,
even though, following current conventions, the official RFC author
list includes only the key editors of the document. The
Acknowledgements section at the end of the document thanks other
people who contributed to this document in some form.
2. History of Internet Research and Research Funding
2.1. Prior to 1980
Most of the early research into packet-switched networks was
sponsored by the U.S. Defense Advanced Research Projects Agency
(DARPA) [CSTB99]. This includes the initial design, implementation,
and deployment of the ARPAnet connecting several universities and
other DARPA contractors. The ARPAnet originally came online in the
late 1960s. It grew in size during the 1970s, still chiefly with
DARPA funding, and demonstrated the utility of packet-switched
networking.
DARPA funding for Internet design started in 1973, just four years
after the initial ARPAnet deployment. The support for Internet
design was one result of prior DARPA funding for packet radio and
packet satellite research. The existence of multiple networks
(ARPAnet, packet radio, and packet satellite) drove the need for
internetworking research. The Internet arose in large measure as a
consequence of DARPA research funding for these three networks -- and
arise only incidentally from the commercially-funded work at Xerox
PARC on Ethernet.
2.2. 1980s and early 1990s
The ARPAnet converted to the Internet Protocol (IP) on January 1,
1983, approximately 20 years before this document was written.
Throughout the 1980s, the U.S. Government continued strong research
and development funding for Internet technology. DARPA continued to
be the key funding source, but was supplemented by other DoD (U.S.
Department of Defense) funding (e.g., via the Defense Data Network
(DDN) program of the Defense Communication Agency (DCA)) and other
U.S. Government funding (e.g., U.S. Department of Energy (DoE)
funding for research networks at DoE national laboratories, (U.S.)
National Science Foundation (NSF) funding for academic institutions).
This funding included basic research, applied research (including
freely distributable prototypes), the purchase of IP-capable
products, and operating support for the IP-based government networks
such as ARPAnet, ESnet, MILnet, the NASA Science Internet, and
NSFnet.
During the 1980s, the U.S. DoD desired to leave the business of
providing operational network services to academic institutions, so
funding for most academic activities moved over to the NSF during the
decade. NSF’s initial work included sponsorship of CSnet in 1981.
By 1986, NSF was also sponsoring various research projects into
networking (e.g., Mills’ work on Fuzzballs). In the late 1980s, NSF
created the NSFnet backbone and sponsored the creation of several NSF
regional networks (e.g., SURAnet) and interconnections with several
international research networks. NSF also funded gigabit networking
research, through the Corporation for National Research Initiatives
(CNRI), starting in the late 1980s. It is important to note that the
NSF sponsorship was focused on achieving core NSF goals, such as
connecting scientists at leading universities to NSF supercomputing
centers. The needs of high-performance remote access to
supercomputers drove the overall NSFnet performance. As a side
effect, this meant that students and faculty at those universities
enjoyed a relatively high-performance Internet environment. As those
students graduated, they drove both commercial use of the Internet
and the nascent residential market. It is no accident that this was
the environment from which the world wide web emerged.
Most research funding outside the U.S. during the 1980s and early
1990s was focused on the ISO OSI networking project or on then-new
forms of network media (e.g., wireless, broadband access). The
European Union was a significant source of research funding for the
networking community in Europe during this period. Some of the best
early work in gigabit networking was undertaken in the UK and Sweden.
2.3. Mid-1990s to 2003
Starting in the middle 1990s, U.S. Government funding for Internet
research and development was significantly reduced. The premise for
this was that the growing Internet industry would pay for whatever
research and development that was needed. Some funding for Internet
research and development has continued in this period from European
and Asian organizations (e.g., the WIDE Project in Japan [WIDE]).
Reseaux IP Europeens [RIPE] is an example of market-funded networking
research in Europe during this period.
Experience during this period has been that commercial firms have
often focused on donating equipment to academic institutions and
promoting somewhat vocationally-focused educational projects. Many
of the commercially-funded research and development projects appear
to have been selected because they appeared likely to give the
funding source a specific short-term economic advantage over its
competitors. Higher risk, more innovative research proposals
generally have not been funded by industry. A common view in Silicon
Valley has been that established commercial firms are not very good
at transitioning cutting edge research into products, but were
instead good at buying small startup firms who had successfully
transitioned such cutting edge research into products.
Unfortunately, small startup companies are generally unable
financially to fund any research themselves.
2.4. Current Status
The result of reduced U.S. Government funding and profit-focused,
low-risk, short-term industry funding has been a decline in higher-
risk but more innovative research activities. Industry has also been
less interested in research to evolve the overall Internet
architecture, because such work does not translate into a competitive
advantage for the firm funding such work.
The IAB believes that it would be helpful for governments and other
non-commercial sponsors to increase their funding of both basic
research and applied research relating to the Internet, and to
sustain these funding levels going forward.
3. Open Internet Research Topics
This section primarily discusses some specific topics that the IAB
believes merit additional research. Research, of course, includes
not just devising a theory, algorithm, or mechanism to accomplish a
goal, but also evaluating the general efficacy of the approach and
then the benefits vs. the costs of deploying that algorithm or
mechanism. Important cautionary notes about this discussion are
given in the next sub-section. This particular set of topics is not
intended to be comprehensive, but instead is intended to demonstrate
the breadth of open Internet research questions.
Other discussions of problems of the Internet that merit further
research include the following:
[CIPB02,Claffy03a,Floyd,NSF03a,NSF03b].
3.1. Scope and Limitations
This document is NOT intended as a guide for public funding agencies
as to exactly which projects or proposals should or should not be
funded.
In particular, this document is NOT intended to be a comprehensive
list of *all* of the research questions that are important to further
the evolution of the Internet; that would be a daunting task, and
would presuppose a wider and more intensive effort than we have
undertaken in this document.
Similarly, this document is not intended to list the research
questions that are judged to be only of peripheral importance, or to
survey the current (global; governmental, commercial, and academic)
avenues for funding for Internet research, or to make specific
recommendations about which areas need additional funding. The
purpose of the document is to persuade the reader that ongoing
research is needed towards the continued evolution of the Internet
infrastructure; the purpose is not to make binding pronouncements
about which specific areas are and are not worthy of future funding.
For some research clearly relevant to the future evolution of the
Internet, there are grand controversies between competing proposals
or competing schools of thought; it is not the purpose of this
document to take positions in these controversies, or to take
positions on the nature of the solutions for areas needing further
research.
That all carefully noted, the remainder of this section discusses a
broad set of research areas, noting a subset of particular topics of
interest in each of those research areas. Again, this list is NOT
comprehensive, but rather is intended to suggest that a broad range
of ongoing research is needed, and to propose some candidate topics.
3.1.1. Terminology
Several places in this document refer to ’network operators’. By
that term, we intend to include anyone or any organization that
operates an IP-based network; we are not using that term in the
narrow meaning of commercial network service providers.
3.2. Naming
The Internet currently has several different namespaces, including IP
addresses, sockets (specified by the IP address, upper-layer
protocol, and upper-layer port number), Autonomous System (AS)
number, and the Fully-Qualified Domain Name (FQDN). Many of the
Internet’s namespaces are supported by the widely deployed Domain
Name System [RFC-3467] or by various Internet applications [RFC-2407,
Section 4.6.2.1]
3.2.1. Domain Name System (DNS)
The DNS system, while it works well given its current constraints,
has several stress points.
The current DNS system relies on UDP for transport, rather than SCTP
or TCP. Given the very large number of clients using a typical DNS
server, it is desirable to minimize the state on the DNS server side
of the connection. UDP does this well, so it is a reasonable choice,
though this has other implications, for example a reliance on UDP
fragmentation. With IPv6, intermediate fragmentation is not allowed
and Path MTU Discovery is mandated. However, the amount of state
required to deploy Path MTU Discovery for IPv6 on a DNS server might
be a significant practical problem.
One implication of this is that research into alternative transport
protocols, designed more for DNS-like applications where there are
very many clients using each server, might be useful. Of particular
interest would be transport protocols with little burden for the DNS
server, even if that increased the burden somewhat for the DNS
client.
Additional study of DNS caching, both currently available caching
techniques and also of potential new caching techniques, might be
helpful in finding ways to reduce the offered load for a typical DNS
server. In particular, examination of DNS caching through typical
commercial firewalls might be interesting if it lead to alternative
firewall implementations that were less of an obstacle to DNS
caching.
The community lacks a widely-agreed-upon set of metrics for measuring
DNS server performance. It would be helpful if people would
seriously consider what characteristics of the DNS system should be
measured.
Some in the community would advocate replacing the current DNS system
with something better. Past attempts to devise a better approach
have not yielded results that persuaded the community to change.
Proposed work in this area could be very useful, but might require
careful scrutiny to avoid falling into historic design pitfalls.
With regards to DNS security, major technical concerns include
finding practical methods for signing very large DNS zones (e.g., and
tools to make it easier to manage secure DNS infrastructure.
Most users are unable to distinguish a DNS-related failure from a
more general network failure. Hence, maintaining the integrity and
availability of the Domain Name System is very important for the
future health of the Internet.
3.2.2. New Namespaces
Additionally, the Namespace Research Group (NSRG) of the Internet
Research Task Force (IRTF) studied adding one or more additional
namespaces to the Internet Architecture [LD2002]. Many members of
the IRTF NSRG believe that there would be significant architectural
benefit to adding one or more additional namespaces to the Internet
Architecture. Because smooth consensus on that question or on the
properties of a new namespace was not obtained, the IRTF NSRG did not
make a formal recommendation to the IETF community regarding
namespaces. The IAB believes that this is an open research question
worth examining further.
Finally, we believe that future research into the evolution of
Internet-based distributed computing might well benefit from studying
adding additional namespaces as part of a new approach to distributed
computing.
3.3. Routing
The currently deployed unicast routing system works reasonably well
for most users. However, the current unicast routing architecture is
suboptimal in several areas, including the following: end-to-end
convergence times in global-scale catenets (a system of networks
interconnected via gateways); the ability of the existing inter-
domain path-vector algorithm to scale well beyond 200K prefixes; the
ability of both intra-domain and inter-domain routing to use multiple
metrics and multiple kinds of metrics concurrently; and the ability
of IPv4 and IPv6 to support widespread site multi-homing without
undue adverse impact on the inter-domain routing system. Integrating
policy into routing is also a general concern, both for intra-domain
and inter-domain routing. In many cases, routing policy is directly
tied to economic issues for the network operators, so applied
research into routing ideally would consider economic considerations
as well as technical considerations.