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RFC4057 - IPv6 Enterprise Network Scenarios

王朝other·作者佚名  2008-05-31
窄屏简体版  字體: |||超大  

Network Working Group J. Bound, Ed.

Request for Comments: 4057 Hewlett Packard

Category: Informational June 2005

IPv6 Enterprise Network Scenarios

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 (2005).

Abstract

This document describes the scenarios for IPv6 deployment within

enterprise networks. It defines a small set of basic enterprise

scenarios and includes pertinent questions to allow enterprise

administrators to further refine their deployment scenarios.

Enterprise deployment requirements are discussed in terms of

coexistence with IPv4 nodes, networks and applications, and in terms

of basic network infrastrUCture requirements for IPv6 deployment.

The scenarios and requirements described in this document will be the

basis for further analysis to determine what coexistence techniques

and mechanisms are needed for enterprise IPv6 deployment. The

results of that analysis will be published in a separate document.

Table of Contents

1. Introduction................................................... 2

2. Terminology.................................................... 3

3. Base Scenarios................................................. 4

3.1. Base Scenarios Defined................................... 4

3.2. Scenarios Network Infrastructure Components.............. 5

3.3. Specific Scenario Examples............................... 8

3.4. Applicability Statement..................................10

4. Network Infrastructure Component Requirements..................10

4.1. DNS......................................................11

4.2. Routing..................................................11

4.3. Configuration of Hosts...................................11

4.4. Security.................................................11

4.5. Applications.............................................12

4.6. Network Management.......................................12

4.7. Address Planning.........................................12

4.8. Multicast................................................12

4.9. Multihoming..............................................12

5. Security Considerations........................................12

6. Normative References...........................................13

Acknowledgements...................................................13

1. Introduction

This document describes the scenarios for IPv6 deployment within

enterprise networks. It defines a small set of basic enterprise

scenarios and includes pertinent questions to allow enterprise

administrators to further refine their deployment scenarios.

Enterprise deployment requirements are discussed in terms of

coexistence with IPv4 nodes, networks and applications, and in terms

of basic network infrastructure requirements for IPv6 deployment.

The scenarios and requirements described in this document will be the

basis for further analysis to determine what coexistence techniques

and mechanisms are needed for enterprise IPv6 deployment. The

results of that analysis will be published in a separate document.

The audience for this document is the enterprise network team

considering deployment of IPv6. The document will be useful for

enterprise teams that will have to determine the IPv6 transition

strategy for their enterprise. It is eXPected those teams include

members from management, network operations, and engineering. The

scenarios presented provide an example set of cases the enterprise

can use to build an IPv6 network scenario.

To frame the discussion, this document will describe a set of

scenarios each with a network infrastructure. It is impossible to

define every possible enterprise scenario that will apply to IPv6

adoption and transition.

Each enterprise will select the transition that best supports their

business requirements. Any attempt to define a default or one-size-

fits-all transition scenario, simply will not work. This document

does not try to depict the drivers for adoption of IPv6 by an

enterprise.

While it is difficult to quantify all the scenarios for an enterprise

network team to plan for IPv6, it is possible to depict a set of

abstract scenarios that will assist with planning. This document

presents three base scenarios to be used as models by enterprises

defining specific scenarios.

The first scenario assumes the enterprise decides to deploy IPv6 in

conjunction with IPv4. The second scenario assumes the enterprise

decides to deploy IPv6 because of a specific set of applications that

it wants to use over an IPv6 network. The third scenario assumes an

enterprise is building a new network or restructuring an existing

network and decides to deploy IPv6 as the predominant protocol within

the enterprise coexisting with IPv4. This document then briefly

reviews a set of network infrastructure components that must be

analyzed, which are common to most enterprises.

This document then provides three specific scenario examples using

the network infrastructure components to depict the requirements.

These are common enterprise deployment cases to depict the challenges

for the enterprise to transition a network to IPv6.

Next, supporting legacy functions on the network (while the

transition is in process), and the network infrastructure components

requiring analysis by the enterprise are discussed. The

interoperation with legacy functions within the enterprise will be

required for all transition except possibly by a new network that

will be IPv6 from inception. The network infrastructure components

will depict functions in their networks that require consideration

for IPv6 deployment and transition.

Using the scenarios, network infrastructure components, and examples

in this document, an enterprise can define its specific scenario

requirements. Understanding the legacy functions and network

infrastructure components required, the enterprise can determine the

network operations required to deploy IPv6. The tools and mechanisms

to support IPv6 deployment operations will require enterprise

analysis. The analysis to determine the tools and mechanisms to

support the scenarios will be presented in subsequent document(s).

2. Terminology

Enterprise Network - A network that has multiple internal links, one

or more router connections to one or more

Providers, and is actively managed by a network

operations entity.

Provider - An entity that provides services and

connectivity to the Internet or other private

external networks for the enterprise network.

IPv6 Capable - A node or network capable of supporting both

IPv6 and IPv4.

IPv4 only - A node or network capable of supporting only

IPv4.

IPv6 only - A node or network capable of supporting only

IPv6. This does not imply an IPv6 only stack in

this document.

3. Base Scenarios

Three base scenarios are defined to capture the essential abstraction

set for the enterprise. Each scenario has assumptions and

requirements. This is not an exhaustive set of scenarios, but a base

set of general cases.

Below we use the term network infrastructure to mean the software,

network operations and configuration, and methods used to operate a

network in an enterprise.

For the base scenarios it is assumed that any IPv6 node is IPv6

capable.

3.1. Base Scenarios Defined

Scenario 1: Wide-scale/total dual-stack deployment of IPv4 and IPv6

capable hosts and network infrastructure. Enterprise

with an existing IPv4 network wants to deploy IPv6 in

conjunction with their IPv4 network.

Assumptions: The IPv4 network infrastructure used has an equivalent

capability in IPv6.

Requirements: Do not disrupt existing IPv4 network infrastructure

assumptions with IPv6. IPv6 should be equivalent or

"better" than the network infrastructure in IPv4.

However, it is understood that IPv6 is not required to

solve current network infrastructure problems, not

solved by IPv4. It may also not be feasible to deploy

IPv6 on all parts of the network immediately.

Scenario 2: Sparse IPv6 dual-stack deployment in IPv4 network

infrastructure. Enterprise with an existing IPv4

network wants to deploy a set of particular IPv6

"applications" (application is voluntarily loosely

defined here, e.g., peer to peer). The IPv6 deployment

is limited to the minimum required to operate this set

of applications.

Assumptions: IPv6 software/hardware components for the application

are available, and platforms for the application are

IPv6 capable.

Requirements: Do not disrupt IPv4 infrastructure.

Scenario 3: IPv6-only network infrastructure with some IPv4-capable

nodes/applications needing to communicate over the IPv6

infrastructure. Enterprise deploying a new network or

restructuring an existing network, decides IPv6 is the

basis for most network communication. Some IPv4

capable nodes/applications will need to communicate

over that infrastructure.

Assumptions: Required IPv6 network infrastructure is available, or

available over some defined timeline, supporting the

enterprise plan.

Requirements: Interoperation and Coexistence with IPv4 network

infrastructure and applications are required for

communications.

3.2. Scenarios Network Infrastructure Components

This section defines the network infrastructure that exists for the

above enterprise scenarios. This is not an exhaustive list, but a

base list that can be expanded by the enterprise for specific

deployment scenarios. The network infrastructure components are

presented as functions that the enterprise must analyze as part of

defining their specific scenario. The analysis of these functions

will identify actions that are required to deploy IPv6.

Network Infrastructure Component 1

Enterprise Provider Requirements

- Is external connectivity required?

- One site vs. multiple sites and are they within different

geographies?

- Leased lines or VPNs?

- If multiple sites, how is the traffic exchanged securely?

- How many global IPv4 addresses are available to the enterprise?

- What is the IPv6 address assignment plan available from the

provider?

- What prefix delegation is required by the Enterprise?

- Will the enterprise be multihomed?

- What multihoming techniques are available from the provider?

- Will clients within the enterprise be multihomed?

- Does the provider offer any IPv6 services?

- Which site-external IPv6 routing protocols are required?

- Is there an external data center to the enterprise, such as

servers located at the Provider?

- Is IPv6 available using the same Access links as IPv4, or

different ones?

Network Infrastructure Component 2

Enterprise Application Requirements

- List of applications in use?

- Which applications must be moved to support IPv6 first?

- Can the application be upgraded to IPv6?

- Will the application have to support both IPv4 and IPv6?

- Do the enterprise platforms support both IPv4 and IPv6?

- Do the applications have issues with NAT v4-v4 and NAT v4-v6?

- Do the applications need globally routable IP addresses?

- Do the applications care about dependency between IPv4 and IPv6

addresses?

- Are applications run only on the internal enterprise network?

Network Infrastructure Component 3

Enterprise IT Department Requirements

- Who "owns"/"operates" the network: in house or outsourced?

- Is working remotely (i.e., through VPNs) supported?

- Are inter-site communications required?

- Is network mobility used or required for IPv6?

- What are the requirements of the IPv6 address plan?

- Is there a detailed asset management database, including hosts,

IP/MAC addresses, etc.?

- What is the enterprise's approach to numbering geographically

separate sites that have their own Service Providers?

- What will be the internal IPv6 address assignment procedure?

- What site internal IPv6 routing protocols are required?

- What will be the IPv6 Network Management policy/procedure?

- What will be the IPv6 QOS policy/procedure?

- What will be the IPv6 Security policy/procedure?

- What is the IPv6 training plan to educate the enterprise?

- What network operations software will be impacted by IPv6?

- DNS

- Management (SNMP & ad-hoc tools)

- Enterprise Network Servers Applications

- Mail Servers

- High Availability Software for Nodes

- Directory Services

- Are all these software functions upgradeable to IPv6?

- If not upgradeable, then what are the workarounds?

- Do any of the software functions store, display, or allow input

of IP addresses?

- Other services (e.g., NTP, etc.)

- What network hardware will be impacted by IPv6?

- Routers/switches

- Printers/Faxes

- Firewalls

- Intrusion Detection

- Load balancers

- VPN Points of Entry/Exit

- Security Servers and Services

- Network Interconnect for Platforms

- Intelligent Network Interface Cards

- Network Storage Devices

- Are all these hardware functions upgradeable to IPv6?

- If not, what are the workarounds?

- Do any of the hardware functions store, display, or allow input

of IP addresses?

- Are the nodes moving within the enterprise network?

- Are the nodes moving outside and inside the enterprise

network?

Network Infrastructure Component 4

Enterprise Network Management System

- Performance Management required?

- Network Management applications required?

- Configuration Management required?

- Policy Management and Enforcement required?

- Security Management required?

- Management of Transition Tools and Mechanisms?

- What new considerations does IPv6 create for Network Management?

Network Infrastructure Component 5

Enterprise Network Interoperation and Coexistence

- What platforms are required to be IPv6 capable?

- What network ingress and egress points to the site are required

to be IPv6 capable?

- What transition mechanisms are needed to support IPv6 network

operations?

- What policy/procedures are required to support the transition to

IPv6?

- What policy/procedures are required to support interoperation

with legacy nodes and applications?

3.3. Specific Scenario Examples

This section presents a set of base scenario examples and is not an

exhaustive list of examples. These examples were selected to provide

further clarity for base scenarios within an enterprise of a less

abstract nature. The example networks may use the scenarios depicted

in 3.1 and the infrastructure components in 3.2, but there are no

direct implications specifically within these example networks.

Section 3.1, 3.2, and 3.3 should be used in unison for enterprise

IPv6 deployment planning and analysis.

Example Network A:

A distributed network across a number of geographically

separated campuses.

- External network operation.

- External connectivity required.

- Multiple sites connected by leased lines.

- Provider independent IPv4 addresses.

- ISP does not offer IPv6 service.

- Private Leased Lines no Service Provider used.

Applications run by the enterprise:

- Internal Web/Mail.

- File servers.

- Java applications.

- Collaborative development tools.

- Enterprise Resource applications.

- Multimedia applications.

- Financial Enterprise applications.

- Data Warehousing applications.

Internal network operation:

- In house operation of the network.

- DHCP (v4) is used for all desktops; servers use static address

configuration.

- The DHCP server that updates naming records for dynamic desktops

uses dynamic DNS.

- A web based tool is used to enter name to address mappings for

statically addressed servers.

- Network management is done using SNMP.

- All routers and switches are upgradeable to IPv6.

- Existing firewalls can be upgraded to support IPv6 rules.

- Load balancers do not support IPv6, upgrade path unclear.

- Peer-2-Peer Application and Security supported.

- IPv4 Private address space is used within the enterprise.

Example Network B:

A bank running a large network supporting online

transaction processing (OLTP) across a distributed

multi-sited network, with access to a central database

on a remote network from the OLTP network.

- External connectivity not required.

- Multiple sites connected by VPN.

- Multiple sites connected by Native IP protocol.

- Private address space used with NAT.

- Connections to private exchanges.

Applications in the enterprise:

- ATM transaction application.

- ATM management application.

- Financial Software and Database.

- Part of the workforce is mobile and requires access to the

enterprise from outside networks.

Internal Network Operation:

- Existing firewalls can be upgraded to support IPv6 rules.

- Load balancers do not support IPv6, upgrade path unclear.

- Identifying and managing each node's IP address.

Example Network C:

A Security Defense, Emergency, or other Mission Critical network

operation:

- External network required at secure specific points.

- Network is its own Internet.

- Network must be able to absorb ad-hoc creation of sub-networks.

- Entire parts of the network are completely mobile.

- All nodes on the network can be mobile (including routers).

- Network high-availability is mandatory.

- Network must be able to be managed from ad-hoc location.

- All nodes must be able to be configured from stateless mode.

Applications run by the Enterprise:

- Multimedia streaming of audio, video, and data for all nodes.

- Data computation and analysis on stored and created data.

- Transfer of data coordinate points to sensor devices.

- Data and Intelligence gathering applications from all nodes.

Internal Network Operations:

- All packets must be secured end-2-end with encryption.

- Intrusion Detection exists on all network entry points.

- Network must be able to bolt on to the Internet to share

bandwidth as required from Providers.

- VPNs can be used, but NAT can never be used.

- Nodes must be able to access IPv4 legacy applications over IPv6

network.

3.4. Applicability Statement

The specific network scenarios selected are chosen to depict a base

set of examples, and to support further analysis of enterprise

networks. This is not a complete set of network scenarios. Though

Example Network C is a verifiable use case, currently the scenario

defines an early adopter of enterprise networks transitioning to IPv6

as a predominant protocol strategy (i.e., IPv6 Routing, Applications,

Security, and Operations), viewing IPv4 as legacy operations

immediately in the transition strategy, and at this time may not be

representative of many initial enterprise IPv6 deployments. Each

enterprise planning team will need to make that determination as IPv6

deployment evolves.

4. Network Infrastructure Component Requirements

The enterprise will need to determine which network infrastructure

components require enhancements or need to be added for deployment of

IPv6. This infrastructure will need to be analyzed and understood as

a critical resource to manage. The list in this section is not

exhaustive, but contains the essential network infrastructure

components for the enterprise to consider before beginning to define

more fine-tuned requirements such as QOS, PKI, or Bandwidth

requirements for IPv6. The components are only identified here and

their details will be discussed in the analysis document for

enterprise scenarios. References currently available for components

are provided.

4.1. DNS

DNS will now have to support both IPv4 and IPv6 DNS records and the

enterprise will need to determine how the DNS is to be managed and

accessed, and secured. The range of DNS operational issues is beyond

the scope of this document. However, DNS resolution and transport

solutions for both IP protocols are influenced by the chosen IPv6

deployment scenario. Users need to consider all current DNS IPv4

operations and determine if those operations are supported for IPv6

[DNSV6].

4.2. Routing

Interior and Exterior routing will be required to support both IPv4

and IPv6 routing protocols, and the coexistence of IPv4 and IPv6 over

the enterprise network. The enterprise will need to define the IPv6

routing topology, any ingress and egress points to provider networks,

and transition mechanisms that they wish to use for IPv6 adoption.

The enterprise will also need to determine what IPv6 transition

mechanisms are supported by their upstream providers.

4.3. Configuration of Hosts

IPv6 introduces the concept of stateless autoconfiguration in

addition to stateful autoconfiguration, for the configuration of

hosts within the enterprise. The enterprise will have to determine

the best method of host configuration for its network, if it will use

stateless or stateful autoconfiguration, and how autoconfiguration

will operate for DNS updates. It will also need to determine how

prefix delegation will be done from their upstream provider and how

those prefixes will be cascaded down to the enterprise IPv6 network.

The policy for DNS or choice of autoconfiguration is out of scope for

this document [CONF, DHCPF, DHCPL].

4.4. Security

Current existing mechanisms used for IPv4 to provide security need to

be supported for IPv6 within the enterprise. IPv6 should create no

new security concerns for IPv4. The entire security infrastructure

currently used in the enterprise needs to be analyzed against IPv6

deployment effect to determine what is supported in IPv6. Users

should review other current security IPv6 network infrastructure work

in the IETF and within the industry. Users will have to work with

their platform and software providers to determine which IPv6

security network infrastructure components are supported. The

security filters and firewall requirements for IPv6 need to be

determined by the enterprise. The policy choice of users for

security is beyond the scope of this document.

4.5. Applications

Existing applications will need to be ported or provide proxies to

support both IPv4 and IPv6 [APPS].

4.6. Network Management

The addition of IPv6 network infrastructure components will need to

be managed by the enterprise network operations center. Users will

need to work with their network management platform providers to

determine what is supported for IPv6 while planning IPv6 adoption,

and which tools are available to monitor the network. Network

management will not need to support both IPv4 and IPv6 and view nodes

as dual stacks.

4.7. Address Planning

The address space within the enterprise will need to be defined and

coordinated with the routing topology of the enterprise network. It

is also important to identify the pool of IPv4 address space

available to the enterprise to assist with IPv6 transition methods.

4.8. Multicast

Enterprises utilizing IPv4 Multicast services will need to consider

how these services may be implemented operationally in an IPv6-

enabled environment.

4.9. Multihoming

At this time, current IPv6 allocation policies are mandating the

allocation of IPv6 address space from the upstream provider. If an

enterprise is multihomed, the enterprise will have to determine how

it wishes to support multihoming. This also is an area of study

within the IETF and work in progress.

5. Security Considerations

This document lists scenarios for the deployment of IPv6 in

enterprise networks, and there are no security considerations

associated with making such a list.

There will be security considerations for the deployment of IPv6 in

each of these scenarios, but they will be addressed in the document

that includes the analysis of each scenario.

6. Normative References

[DNSV6] Durand, A., Ihren, J., and P. Savola, "Operational

Considerations and Issues with IPv6 DNS", Work in Progress.

[CONF] Thomson, S. and T. Narten, "IPv6 Stateless Address

Autoconfiguration", RFC 2462, December 1998.

[DHCPF] Droms, R., Bound, J., Volz, B., Lemon, T., Perkins, C., and

M. Carney, "Dynamic Host Configuration Protocol for IPv6

(DHCPv6)", RFC 3315, July 2003

[DHCPL] Nikander, P., Kempf, J., and E. Nordmark, "IPv6 Neighbor

Discovery (ND) Trust Models and Threats", RFC 3756, May

2004.

[APPS] Shin, M-K., Hong, Y-G., Hagino, J., Savola, P., and E.

Castro, "Application ASPects of IPv6 Transition", RFC 4038,

March 2005.

Acknowledgements

The Authors would like to acknowledge contributions from the

following: IETF v6ops Working Group, Alan Beard, Brian Carpenter,

Alain Durand, Bob Hinden, and Pekka Savola.

Authors' Addresses

Yanick Pouffary (Chair of Design Team)

HP Competency Center

950, Route des Colles, BP027,

06901 Sophia Antipolis CEDEX

FRANCE

Phone: + 33492956285

EMail: Yanick.pouffary@hp.com

Jim Bound (Editor)

Hewlett Packard

110 Spitbrook Road

Nashua, NH 03062

USA

Phone: (603) 884-0062

EMail: jim.bound@hp.com

Marc Blanchet

Viagenie inc.

2875 boul. Laurier, bur. 300

Ste-Foy, Quebec, G1V 2M2

Canada

EMail: Marc.Blanchet@viagenie.qc.ca

Tony Hain

Cisco Systems

500 108th Ave. N.E. Suite 400

Bellevue, WA 98004

USA

EMail: alh-ietf@tndh.net

Paul Gilbert

Cisco Systems

1 Penn Plaza, 5th floor,

NY, NY 10119

USA

Phone: (212) 714-4334

EMail: pgilbert@cisco.com

Margaret Wasserman

ThingMagic

One Broadway

Cambridge, MA 02142

USA

Phone: (617) 758-4177

EMail: margaret@thingmagic.com

Jason Goldschmidt

Sun Microsystems

M/S UMPK17-103

17 Network Circle

Menlo Park, CA 94025

USA

Phone: (650) 786-3502

Fax: (650) 786-8250

EMail: jason.goldschmidt@sun.com

Aldrin Isaac

Bloomberg L.P.

499 Park Avenue

New York, NY 10022

USA

Phone: (212) 940-1812

EMail: aisaac@bloomberg.com

Tim Chown

School of Electronics and Computer Science

University of Southampton

Southampton SO17 1BJ

United Kingdom

EMail: tjc@ecs.soton.ac.uk

Jordi Palet Martinez

Consulintel

San Jose Artesano, 1

Madrid, SPAIN

Phone: +34 91 151 81 99

Fax: +34 91 151 81 98

EMail: jordi.palet@consulintel.es

Fred Templin

Nokia

313 Fairchild Drive

Mountain View, CA 94043

USA

Phone: (650) 625-2331

EMail: ftemplin@iprg.nokia.com

Roy Brabson

IBM

PO BOX 12195

3039 Cornwallis Road

Research Triangle Park, NC 27709

USA

Phone: (919) 254-7332

EMail: rbrabson@us.ibm.com

Full Copyright Statement

Copyright (C) The Internet Society (2005).

This document is subject to the rights, licenses and restrictions

contained in BCP 78, and except as set forth therein, the authors

retain all their rights.

This document and the information contained herein are provided on an

"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS

OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET

ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,

INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE

INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED

WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Intellectual Property

The IETF takes no position regarding the validity or scope of any

Intellectual Property Rights or other rights that might be claimed to

pertain to the implementation or use of the technology described in

this document or the extent to which any license under such rights

might or might not be available; nor does it represent that it has

made any independent effort to identify any such rights. Information

on the procedures with respect to rights in RFC documents can be

found in BCP 78 and BCP 79.

Copies of IPR disclosures made to the IETF Secretariat and any

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Acknowledgement

Funding for the RFC Editor function is currently provided by the

Internet Society.

 
 
 
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