Network Working Group E. Fleischman
Request for Comments: 1687 Boeing Computer Services
Category: Informational August 1994
A Large Corporate User"s View of IPng
Status of this Memo
This memo provides information for the Internet community. This memo
does not specify an Internet standard of any kind. Distribution of
this memo is unlimited.
Abstract
This document was submitted to the IETF IPng area in response to RFC
1550. Publication of this document does not imply acceptance by the
IPng area of any ideas eXPressed within. Comments should be
submitted to the big-internet@munnari.oz.au mailing list.
Disclaimer and Acknowledgments
MUCh of this draft has been adapted from the article "A User"s View
of IPng" by Eric Fleischman which was published in the September 1993
edition of ConneXions Magazine (Volume 7, Number 9, pages 36 - 40).
The original ConneXions article represented an official position of
The Boeing Company on IPng issues. This memo is an expansion of that
original treatment. This version also represents a Boeing corporate
opinion which we hope will be helpful to the on-going IPng
discussions. An assumption of this paper is that other Fortune 100
companies which have non-computing-related products and services will
tend to have a viewpoint about IPng which is similar to the one
presented by this paper.
Executive Summary
Key points:
1) Large corporate users generally view IPng with disfavor.
2) Industry and the IETF community have very different values
and viewpoints which lead to orthogonal assessments concerning
the desirability of deploying IPng.
3) This paper provides insight into the mindset of a large
corporate user concerning the relevant issues surrounding an
IPng deployment. The bottom line is that a new deployment of
IPng runs counter to several business drivers. A key point to
highlight is that end users actually buy applications -- not
networking technologies.
4) There are really only two compelling reasons for a large end
user to deploy IPng:
A) The existence of must-have products which are tightly coupled
with IPng.
B) Receipt of a command to deploy IPng from senior management.
The former would probably be a function of significant
technological advances. The latter probably would be a
function of a convergence of IPng with International
Standards (OSI).
5) Five end user requirements for IPng are presented:
A) The IPng approach must permit piecemeal transitions.
B) The IPng approach must not hinder technological advances.
C) The IPng approach is expected to foster synergy with
International Standards (OSI).
D) The IPng approach should have "Plug and Play" networking
capabilities.
E) The IPng approach must have network security characteristics
which are better than existing IPv4 protocols.
Introduction
The goal of this paper is to examine the implications of IPng from
the point of view of Fortune 100 corporations which have heavily
invested in TCP/IP technology in order to achieve their (non-computer
related) business goals.
It is our perspective that End Users currently view IPng with
disfavor. This note seeks to explain some of the reasons why an end
user"s viewpoint may differ significantly from a "traditional IETF"
perspective. It addresses some of the reasons which cause IPng to be
viewed by end users as a "threat" rather than as an "opportunity".
It enumerates some existing End User dissatisfactions with IPv4
(i.e., current TCP/IP network layer). These dissatisfactions may
perhaps be eventually exploited to "sell" IPng to users. Finally, it
identifies the most compelling reasons for end users to deploy IPng.
In any case, the IETF community should be warned that their own
enthusiasm for IPng is generally not shared by end users and that
convincing end users to deploy IPng technologies may be very
difficult -- assuming it can be done at all.
The Internet and TCP/IP Protocols are not Identical
The Internet Engineering Task Force (IETF) community closely
associates TCP/IP protocols with the Internet. In many cases it is
difficult to discern from the IETF perspective where the world-wide
Internet infrastructure ends and the services of the TCP/IP Protocol
Suite begin -- they are not always distinguishable from each other.
Historically they both stem from the same roots: DARPA was the
creator of TCP/IP and of the seminal "Internet". The services
provided by the Internet have been generally realized by the "TCP/IP
protocol family". The Internet has, in turn, become a primary
vehicle for the definition, development, and transmission of the
various TCP/IP protocols in their various stages of maturity. Thus,
the IETF community has a mindset which assumes that there is a strong
symbiotic relationship between the two.
End users do not share this assumption -- despite the fact that many
end users have widely deployed TCP/IP protocols and extensively use
the Internet. It is important for the IETF community to realize,
however, that TCP/IP protocols and the Internet are generally viewed
to be two quite dissimilar things by the large end user. That is,
while the Internet may be a partial selling point for some TCP/IP
purchases, it is rarely even a primary motivation for the majority of
purchases. Many end users, in fact, have sizable TCP/IP deployments
with no Internet connectivity at all. Thus, many end users view the
relationship between the Internet and TCP/IP protocols to be tenuous
at best.
More importantly, many corporations have made substantial investments
in (non-Internet) external communications infrastructures. A variety
of reasons account for this including the fact that until recently
the Internet was excluded from the bilateral agreements and
international tariffs necessary for international commerce. In any
case, end users today are not (in the general case) dependent upon
the Internet to support their business processes. [Note: the
previous sentence does not deny that many Fortune 100 employees (such
as the author) are directly dependent upon the Internet to fulfill
their job responsibilities: The Internet has become an invaluable
tool for many corporations" "research and education" activities.
However, it is rarely used today for activities which directly affect
the corporations" financial "bottom line": commerce.] By contrast,
large End Users with extensive internal TCP/IP deployments may
perhaps view TCP/IP technology to be critically important to their
corporation"s core business processes.
Security Islands
Another core philosophical difference between large end users and the
IETF is concerning the importance of Security Islands (i.e.,
firewalls). The prevalent IETF perspective is that Security Islands
are "A Bad Thing". The basic IETF assumption is that the
applications they are designing are universally needed and that
Security Islands provide undesirable filters for that usage. That
is, the IETF generally has a world view which presupposes that data
Access should be unrestricted and widely available.
By contrast, corporations generally regard data as being a
"sensitive" corporate asset: If compromised the very viability of
the corporation itself may in some cases be at risk. Corporations
therefore presuppose that data exchange should be restricted.
Large end users also tend to believe that their employees have
differing data access needs: Factory workers have different
computing needs than accountants who have different needs than
aeronautical engineers who have different needs than research
scientists. A corporation"s networking department(s) seeks to ensure
that each class of employee actually receives the type of services
they require. A security island is one of the mechanisms by which
the appropriate service levels may be provided to the appropriate
class of employee, particularly in regards to external access
capabilities.
More importantly, there are differing classes of computer resources
within a corporation. A certain percentage of these resources are
absolutely critical to the continuing viability of that corporation.
These systems should never (ever) be accessible from outside of the
company. These "corporate jewels" must be protected by viable
security mechanisms. Security islands are one very important
component within a much larger total security solution.
For these reasons we concur with the observation made by Yakov
Rekhter (of IBM) and Bob Moskowitz (of Chrysler) in their joint
electronic mail message of January 28, 1994. They wrote:
"Hosts within sites that use IP can be partitioned into three
categories:
- hosts that do not require Internet access.
- hosts that need access to a limited set of Internet
services (e.g., Email, FTP, netnews, remote login) which can
be handled by application layer relays.
- hosts that need unlimited access (provided via IP
connectivity) to the Internet."
The exact mechanism by which a corporation will satisfy the differing
needs of these three classes of devices must be independently
determined by that corporation based upon a number of internal
factors. Each independent solution will determine how that
corporation defines their own version of "security island".
Thus, if end users use the Internet at all, they will generally do so
through a "security island" of their own devising. The existence of
the security island is yet another element to (physically and
emotionally) decouple the End User from the Internet. That is, while
the end user may use the Internet, their networks (in the general
case) are neither directly attached to it nor are their core business
processes today critically dependent upon it.
Networking from a Large End User"s Perspective
The following five key characteristics describe Boeing"s environment
and are probably generally representative of other large TCP/IP
deployments. The author believes that an understanding of these
characteristics is very important for oBTaining insight into how the
large end user is likely to view IPng.
1) Host Ratio
Many corporations explicitly try to limit the number of their
TCP/IP hosts that are directly accessible from the Internet. This
is done for a variety of reasons (e.g., security). While the
ratio of those hosts that have direct Internet access capabilities
to those hosts without such capabilities will vary from company to
company, ratios ranging from 1:1000 to 1:10,000 (or more) are not
uncommon. The implication of this point is that the state of the
world-wide (IPv4) Internet address space only directly impacts a
tiny percentage of the currently deployed TCP/IP hosts within a
large corporation. This is true even if the entire population is
currently using Internet-assigned addresses.
2) Router-to-Host Ratio
Most corporations have significantly more TCP/IP hosts than they
have IP routers. Ratios ranging between 100:1 to 600:1 (or more)
are common. The implication of this point is that a transition
approach which solely demands changes to routers is generally much
less disruptive to a corporation than an approach which demands
changes to both routers and hosts.
3) Business Factor
Large corporations exist to fulfill some business purpose such as
the construction of airplanes, baseball bats, cars, or some other
product or service offering. Computing is an essential tool to
help automate business processes in order to more efficiently
accomplish the business goals of the corporation. Automation is
accomplished via applications. Data communications, operating
systems, and computer hardware are the tools used by applications
to accomplish their goals. Thus, users actually buy applications
and not networking technologies. The central lesson of this point
is that IPng will be deployed according to the applications which
use it and not because it is a better technology.
4) Integration Factor
Large corporations currently support many diverse computing
environments. This diversity limits the effectiveness of a
corporation"s computing assets by hindering data sharing,
application interoperability, "application portability", and
software re-usability. The net effect is stunted application life
cycles and increased support costs. Data communications is but
one of the domains which contribute towards this diversity. For
example, The Boeing Company currently has deployed at least
sixteen different protocol families within its networks (e.g.,
TCP/IP, SNA, DECnet, OSI, IPX/SPX, AppleTalk, XNS, etc.). Each
distinct Protocol Family population potentially implies unique
training, administrative, support, and infrastructure
requirements. Consequently, corporate goals often exist to
eliminate or merge diverse Data Communications Protocol Family
deployments in order to reduce network support costs and to
increase the number of devices which can communicate together
(i.e., foster interoperability). This results in a basic
abhorrence to the possibility of introducing "Yet Another
Protocol" (YAP). Consequently, an IPng solution which introduces
an entirely new set of protocols will be negatively viewed simply
because its by-products are more roadblocks to interoperability
coupled with more work, expense, and risk to support the end
users" computing resources and business goals. Having said this,
it should be observed that this abhorrence may be partially
overcome by "extenuating circumstances" such as applications using
IPng which meet critical end-user requirements or by broad
(international) commercial support.
5) Inertia Factor
There is a natural tendency to continue to use the current IP
protocol (IPv4) regardless of the state of the Internet"s IPv4
address space. Motivations supporting inertia include the
following: existing application dependencies (including
Application Programming Interface (API) dependencies); opposition
to additional protocol complexity; budgetary constraints limiting
additional hardware/software expenses; additional address
management and naming service costs; transition costs; support
costs; training costs; etc. As the number of Boeing"s deployed
TCP/IP hosts continues to grow towards the 100,000 mark, the
inertial power of this population becomes increasingly strong.
However, inertia even exists with smaller populations simply
because the cost to convert or upgrade the systems are not
warranted. Consequently, pockets of older "legacy system"
technologies often exist in specific environments (e.g., we still
have pockets of the archaic BSC protocol). The significance of
this point is that unless there are significant business benefits
to justify an IPng deployment, economics will oppose such a
deployment. Thus, even if the forthcoming IPng protocol proves to
be "the ultimate and perfect protocol", it is unrealistic to
imagine that the entire IPv4 population will ever transition to
IPng. This means that should we deploy IPng within our network,
there will be an ongoing requirement for our internal IPng
deployment to be able to communicate with our internal IPv4
community. This requirement is unlikely to go away with time.
Address Depletion Doesn"t Resonate With Users
Thus, the central, bottom-line question concerning IPng from the
large corporate user perspective is: What are the benefits which
will justify the expense of deploying IPng?
At this time we can conceive of only four possible causes which may
motivate us to consider deploying IPng:
Possible Cause: Possible Corporate Response:
1) Many Remote (external) Peers Gateway external systems only.
solely use IPng.
2) Internet requires IPng usage. Gateway external systems only.
3) "Must have" products are tightly Upgrade internal corporate
coupled with IPng (e.g., "flows" network to support IPng where
for real-time applications). that functionality is needed.
4) Senior management directs IPng Respond appropriately.
usage.
It should explicitly be noted that the reasons which are compelling
the Internet Community to create IPng (i.e., the scalability of IPv4
over the Internet) are not themselves adequate motivations for users
to deploy IPng within their own private networks. That is, should
IPng usage become mandated as a prerequisite for Internet usage, a
probable response to this mandate would be to convert our few hosts
with external access capabilities to become IPng-to-IPv4
application-layer gateways. This would leave the remainder of our
vast internal TCP/IP deployment unchanged. Consequently, given
gateways for external access, there may be little motivation for a
company"s internal network to support IPng.
User"s IPv4 "Itches" Needing Scratching
The end user"s "loyalty" to IPv4 should not be interpreted to mean
that everything is necessarily "perfect" with existing TCP/IP
deployments and that there are therefore no "itches" which an
improved IPv4 network layer -- or an IPng -- can"t "scratch". The
purpose of this section is to address some of the issues which are
very troubling to many end users:
A) Security. TCP/IP protocols are commonly deployed upon broadcast
media (e.g., Ethernet Version 2). However, TCP/IP mechanisms to
encrypt passWords or data which traverse this media are
inadequate. This is a very serious matter which needs to be
expeditiously resolved. An integrated and effective TCP/IP
security architecture needs to be defined and become widely
implemented across all venders" TCP/IP products.
B) User Address Space privacy. Current IPv4 network addressing
policies require that end users go to external entities to obtain
IP network numbers for use in their own internal networks. These
external entities have the hubris to determine whether these
network requests are "valid" or not. It is our belief that a
corporation"s internal addressing policies are their own private
affair -- except in the specific instances in which they may
affect others. Consequently, a real need exists for two classes
of IPv4 network numbers: those which are (theoretically) visible
to the Internet today (and thus are subject to external
requirements) and those which will never be connected to the
Internet (and thus are strictly private). We believe that the
concept of "local addresses" is a viable compromise between the
justifiable need of the Internet to steward scarce global
resources and the corporate need for privacy. "Local addresses"
by definition are non-globally-unique addresses which should
never be routed (or seen) by the Internet infrastructure.
We believe that 16 contiguous Class B "local addresses" need to
immediately be made available for internal corporate usage. Such
an availability may also reduce the long-term demand for new IPv4
network numbers (see RFC1597).
C) Self-Defining Networks. Large End Users have a pressing need for
plug-and-play TCP/IP networks which auto-configure, auto-address,
and auto-register. End users have repeatedly demonstrated our
inability to make the current manual methods work (i.e., heavy
penalties for human error). We believe that the existing DHCP
technology is a good beginning in this direction.
D) APIs and network integration. End users have deployed many
differing complex protocol families. We need tools by which
these diverse deployments may become integrated together along
with viable transition tools to migrate proprietary
alternatives to TCP/IP-based solutions. We also desire products
to use "open" multi-vendor, multi-platform, exposed Application
Programming Interfaces (APIs) which are supported across several
data communications protocol "families" to aid in this
integration effort.
E) International Commerce. End users are generally unsure as to
what extent TCP/IP can be universally used for international
commerce today and whether this is a cost-effective and "safe"
option to satisfy our business requirements.
F) Technological Advances. We have ongoing application needs which
demand a continual "pushing" of the existing technology. Among
these needs are viable (e.g., integratable into our current
infrastructures) solutions to the following: mobile hosts,
multimedia applications, real-time applications, very
high-bandwidth applications, improved very low-bandwidth (e.g.,
radio based) applications, standard-TCP/IP-based transaction
processing applications (e.g., multi-vendor distributed
databases).
Only Two Motivations For Users To Deploy IPng
Despite this list of IPv4 problem areas, we suspect that there are
only two causes which may motivate users to widely deploy IPng:
(1) If IPng products add critical functionality which IPv4 can"t
provide (e.g., real time applications, multimedia applications,
genuine (scalable) plug-and-play networking, etc.), users would be
motivated to deploy IPng where that functionality is needed.
However, these deployments must combat the "Integration Factor"
and the "Inertia Factor" forces which have previously been
described. This implies that there must be a significant business
gain to justify such a deployment. While it is impossible to
predict exactly how this conflict would "play out", it is
reasonable to assume that IPng would probably be deployed
according to an "as needed only" policy. Optimally, specific
steps would be taken to protect the remainder of the network from
the impact of these localized changes. Of course, should IPng
become bundled with "killer applications" (i.e., applications
which are extremely important to significantly many key business
processes) then all bets are off: IPng will become widely
deployed. However, it also should be recognized that virtually
all (initial) IPng applications, unless they happen to be "killer
applications", will have to overcome significant hurdles to be
deployed simply because they represent risk and substantially
increased deployment and support costs for the end user.
(2) Should IPng foster a convergence between Internet Standards
and International Standards (i.e., OSI), this convergence could
change IPng"s destiny. That is, the networks of many large
corporations are currently being driven by sets of strong, but
contradictory, requirements: one set demanding compliance with
Internet Standards (i.e., TCP/IP) and another set demanding
compliance with International Standards. This paper assumes that
the reader is already familiar with the many reasons why end users
seek to deploy and use Internet Standards. The following is a
partial list as to why End Users may be motivated to use
International Standards (i.e., OSI) as well:
A) World-wide commerce is regulated by governments in accordance
with their treaties and legal agreements. World-wide
telecommunications are regulated by the ITU (a United Nations
chartered/authorized organization). International Standards
(i.e., OSI) are the only government-sanctioned method for
commercial data communications. ASPects of this picture are
currently in the process of changing.
B) The currently proprietary aeronautical world-wide air-to-ground
and ground-to-ground communications are being replaced by an
OSI-based (CLNP) Aeronautical Telecommunications Network (ATN)
internet which is being built in a number of different national
and international forums including:
* International Civil Aviation Organization (ICAO)
* International Air Transport Association (IATA)
* Airlines Electronic Engineering Committee (AEEC)
"Civil Aviation Authorities, airlines, and private aircraft will
use the ATN to convey two major categories of data traffic among
their computers: Air Traffic Services Communications (ATSC) and
Aeronautical Industry Services Communication (AISC)." [Note: The
data communications of airline passengers are not addressed by
the directive.]
C) A corporation"s customers may have data communications
requirements which are levied upon them by the governments in
which they operate which they, in turn, must support in their
own products in order to fulfill their customers" needs. For
example, Boeing is influenced by existing:
* Computer Aided Logistics Support (CALS; i.e., these are GOSIP
(OSI)-based) requirements for US Department of Defense
contractors.
* Airline requirements emanating from A and B above.
D) The end user perception that once we have deployed
International Standards we will not subsequently be compelled to
migrate by external factors to another technology. Thus, we
would have a "safe" foundation to concentrate upon our real
computing issues such as increased customer satisfaction,
business process flow-time improvements, legacy system
modernization, and cost avoidance.
E) The proposals of entities desiring to obtain contracts with
Governments are evaluated on many subjective and objective
bases. One of the subjective issues may well be the
"responsibility" and "dependability" of the bidder company
including such intangibles as its corporate like-mindedness.
For this reason, as long as the Government has OSI as their
official standard, the bidder may have a subjective advantage if
its corporate policy also includes a similar standard,
particularly if data communications services are being
negotiated.
F) The perception that the need for IPng may imply that IPv4 is
unfit to be a strategic end user alternative. Also, IPng is not
a viable deployment option at this time.
G) Doubts concerning IPv4 scalability (e.g., toasternet: an
algorithmic change in which currently "dumb devices" become
intelligent and suddenly require Internet connectivity).
It currently appears that many of these "OSI motivations" are
undergoing change at this time. This possibility must be tracked
with interest. However, a key point of this section is that a
corporation must base its data communications decisions upon business
requirements. That is, corporations exist to sell products and
services, not to play "networking games".
Thus, if a means could be found to achieve greater synergy
(integration/ adoption) between Internet Standards and International
Standards then corporate management may be inclined to mandate
internal deployment of the merged standards and promote their
external use. Optimally, such a synergy should offer the promise of
reducing currently deployed protocol diversity (i.e., supports the
"Integration Factor" force). Depending on the specific method by
which this convergence is achieved, it may also partially offset the
previously mentioned "Inertia Factor" force, especially if IPng
proves to be a protocol which has already been deployed.
User-based IPng Requirements
From the above one can see that a mandate to use IPng to communicate
over the Internet does not correspondingly imply the need for large
corporate networks to generally support IPng within their networks.
Thus, while the IPv4 scalability limitations are a compelling reason
to identify a specific IPv4 replacement protocol for the Internet,
other factors are at work within private corporate networks. These
factors imply that large TCP/IP end users will have a continuing need
to purchase IPv4 products even after IPng products have become
generally available.
However, since the IETF community is actively engaged in identifying
an IPng solution, it is desirable that the solution satisfy as many
end user needs as possible. For this reason, we would like to
suggest that the following are important "user requirements" for any
IPng solution:
1) The IPng approach must permit users to slowly transition to IPng
in a piecemeal fashion. Even if IPng becomes widely deployed,
it is unrealistic to expect that users will ever transition all
of the extensive IPv4 installed base to IPng. Consequently, the
approach must indefinitely support corporate-internal
communication between IPng hosts and IPv4 hosts regardless of
the requirements of the world-wide Internet.
2) The IPng approach must not hinder technological advances from
being implemented.
3) The IPng approach is expected to eventually foster greater
synergy (integration/adoption) between Internet Standards and
International Standards (i.e., OSI). [Note: This may be
accomplished in a variety of ways including having the Internet
Standards adopted as International Standards or else having the
International Standards adopted as Internet Standards.]
4) The IPng approach should have "self-defining network" (i.e.,
"plug & play") capabilities. That is, large installations
require device portability in which one may readily move devices
within one"s corporate network and have them autoconfigure,
autoaddress, autoregister, etc. without explicit human
administrative overhead at the new location -- assuming that the
security criteria of the new location have been met.
5) The approach must have network security characteristics which are
better than existing IPv4 protocols.
Conclusion
In summary, the key factor which will determine whether -- and to
what extent -- IPng will be deployed by large end users is whether
IPng will become an essential element for the construction of
applications which are critically needed by our businesses. If IPng
is bundled with applications which satisfy critical business needs,
it will be deployed. If it isn"t, it is of little relevance to the
large end user. Regardless of what happens to IPng, the large mass
of IPv4 devices will ensure that IPv4 will remain an important
protocol for the foreseeable future and that continued development of
IPv4 products is advisable.
Security Considerations
Security issues discussed throughout this memo.
Author"s Address
Eric Fleischman
Network Architect
Boeing Computer Services
P.O. Box 24346, MS 7M-HA
Seattle, WA 98124-0346 USA