draft-ietf-webdav-quota-07.txt   rfc4331.txt 
WWW Distributed Authoring and B. Korver
Versioning (webdav) Network Resonance
Internet-Draft L. Dusseault
Expires: October 29, 2005 OSAF
April 27, 2005
Quota and Size Properties for DAV Collections Network Working Group B. Korver
draft-ietf-webdav-quota-07 Request for Comments: 4331 Network Resonance
Category: Standards Track L. Dusseault
Status of this Memo OSAF
February 2006
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http://www.ietf.org/ietf/1id-abstracts.txt. for Distributed Authoring and Versioning (DAV) Collections
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Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2005). Copyright (C) The Internet Society (2006).
Abstract Abstract
WebDAV servers are frequently deployed with quota (size) limitations. Web Distributed Authoring and Versioning (WebDAV) servers are
This document discusses the properties and minor behaviors needed for frequently deployed with quota (size) limitations. This document
clients to interoperate with quota (size) implementations on WebDAV discusses the properties and minor behaviors needed for clients to
interoperate with quota (size) implementations on WebDAV
repositories. repositories.
Table of Contents Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 1. Introduction ....................................................2
1.1 Notational Conventions . . . . . . . . . . . . . . . . . . 3 1.1. Notational Conventions .....................................2
1.2 Requirement for quotas . . . . . . . . . . . . . . . . . . 3 1.2. Requirement for Quotas .....................................2
2. Solution Overview . . . . . . . . . . . . . . . . . . . . . 3 2. Solution Overview ...............................................3
3. DAV:quota-available-bytes . . . . . . . . . . . . . . . . . 4 3. DAV:quota-available-bytes .......................................3
4. DAV:quota-used-bytes . . . . . . . . . . . . . . . . . . . . 5 4. DAV:quota-used-bytes ............................................4
5. Example PROPFIND request and response . . . . . . . . . . . 6 5. Example PROPFIND Request and Response ...........................5
6. Error reporting . . . . . . . . . . . . . . . . . . . . . . 7 6. Error Reporting .................................................6
7. Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 7. Notes ...........................................................6
8. Security Considerations . . . . . . . . . . . . . . . . . . 9 8. Security Considerations .........................................8
9. Internationalization Considerations . . . . . . . . . . . . 9 9. Internationalization Considerations .............................8
10. IANA Considerations . . . . . . . . . . . . . . . . . . . . 9 10. Acknowledgements ...............................................8
11. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9 11. References .....................................................8
12. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 11.1. Normative References ......................................8
12.1 Normative References . . . . . . . . . . . . . . . . . . 9 11.2. Informative References ....................................8
12.2 Informative References . . . . . . . . . . . . . . . . . 9
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . 10
Intellectual Property and Copyright Statements . . . . . . . 11
1. Introduction 1. Introduction
1.1 Notational Conventions 1.1. Notational Conventions
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. document are to be interpreted as described in [RFC2119].
The definition of live property is provided in [RFC2518]. The The definition of live property is provided in [RFC2518]. The
definition of protected and computed properties is provided in definition of protected and computed properties is provided in
[RFC3253], Section 1.4. [RFC3253], Section 1.4.
1.2 Requirement for quotas 1.2. Requirement for Quotas
WebDAV servers based on [RFC2518] have been implemented and deployed WebDAV servers based on [RFC2518] have been implemented and deployed
with quota restrictions on collections and users, so it makes sense with quota restrictions on collections and users, so it makes sense
to standardize this functionality to improve user experience and to standardize this functionality to improve user experience and
client interoperability. client interoperability.
The reasons why WebDAV servers frequently have quotas enforced are The reasons why WebDAV servers frequently have quotas enforced are
the same reasons why any storage system comes with quotas. the same reasons why any storage system comes with quotas.
o Sometimes the storage service charges according to quota o Sometimes the storage service charges according to quota.
o Sometimes the storage service is provided free, but the storage o Sometimes the storage service is provided free, but the storage
service provider has limited storage space (e.g. university- service provider has limited storage space (e.g., university-
provided student accounts) provided student accounts).
o Even in cases where the storage can be upgraded, the storage o Even in cases where the storage can be upgraded, the storage
managers may choose to limit quota in order to encourage users to managers may choose to limit quota in order to encourage users to
limit the files they store on the system and to clean up obsolete limit the files they store on the system and to clean up obsolete
files. (e.g. IT departments within corporations) files (e.g., IT departments within corporations).
In order to work best with repositories that support quotas, client In order to work best with repositories that support quotas, client
software should be able to determine and display the DAV:quota- software should be able to determine and display the DAV:quota-
available-bytes (defined below) on collections. Further, client available-bytes (defined below) on collections. Further, client
software should have some way of fairly reliably determining how much software should have some way of fairly reliably determining how much
storage space is already counted towards that quota. storage space is already counted towards that quota.
Support for the properties defined in this document enhances the Support for the properties defined in this document enhances the
client experience, because the client has a chance of managing its client experience, because the client has a chance of managing its
files to avoid running out of allocated storage space. Clients may files to avoid running out of allocated storage space. Clients may
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2. Solution Overview 2. Solution Overview
The approach to meeting the requirements and scenarios outlined above The approach to meeting the requirements and scenarios outlined above
is to define two live properties. This specification can be met on a is to define two live properties. This specification can be met on a
server by implementing both DAV:quota-available-bytes and DAV:quota- server by implementing both DAV:quota-available-bytes and DAV:quota-
used-bytes on collections only. used-bytes on collections only.
A <DAV:allprop> PROPFIND request SHOULD NOT return any of the A <DAV:allprop> PROPFIND request SHOULD NOT return any of the
properties defined by this document. However, these property names properties defined by this document. However, these property names
MUST be returned in a <DAV:propname> request for a resource that MUST be returned in a <DAV:propname> request for a resource that
supports the properties, except in the case of infinite limits which supports the properties, except in the case of infinite limits, which
are explained below. are explained below.
The DAV:quota-available-bytes and DAV:quota-used-bytes definitions The DAV:quota-available-bytes and DAV:quota-used-bytes definitions
below borrow heavily from the quota definitions in the NFS [RFC3530] below borrow heavily from the quota definitions in the Network File
specification. System (NFS) [RFC3530] specification.
3. DAV:quota-available-bytes 3. DAV:quota-available-bytes
Name: quota-available-bytes Name: quota-available-bytes
Namespace: DAV: Namespace: DAV:
Purpose: Indicates the maximum amount of additional storage available Purpose: Indicates the maximum amount of additional storage available
to be allocated to a resource. to be allocated to a resource.
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allocations will be refused. It is understood that this space may be allocations will be refused. It is understood that this space may be
consumed by allocations to other resources. consumed by allocations to other resources.
Support for this property is REQUIRED on collections, and OPTIONAL on Support for this property is REQUIRED on collections, and OPTIONAL on
other resources. A server SHOULD implement this property for each other resources. A server SHOULD implement this property for each
resource that has the DAV:quota-used-bytes property. resource that has the DAV:quota-used-bytes property.
Clients SHOULD expect that as the DAV:quota-available-bytes on a Clients SHOULD expect that as the DAV:quota-available-bytes on a
resource approaches 0, further allocations to that resource may be resource approaches 0, further allocations to that resource may be
refused. A value of 0 indicates that users will probably not be able refused. A value of 0 indicates that users will probably not be able
to perform operations that write additional information (e.g. a PUT to perform operations that write additional information (e.g., a PUT
inside a collection), but may be able to replace through overwrite an inside a collection), but may be able to replace through overwrite an
existing resource of equal size. existing resource of equal size.
Note that there may be a number of distinct but overlapping limits, Note that there may be a number of distinct but overlapping limits,
which may even include physical media limits. When reporting DAV: which may even include physical media limits. When reporting DAV:
quota-available-bytes, the server is at liberty to choose any of quota-available-bytes, the server is at liberty to choose any of
those limits but SHOULD do so in a repeatable way. The rule may be those limits but SHOULD do so in a repeatable way. The rule may be
configured per repository, or may be "choose the smallest number". configured per repository, or may be "choose the smallest number".
If a resource has no quota enforced or unlimited storage ("infinite If a resource has no quota enforced or unlimited storage ("infinite
limits"), the server MAY choose not to return this property (404 Not limits"), the server MAY choose not to return this property (404 Not
Found response in Multi-Status), although this specification Found response in Multi-Status), although this specification
RECOMMENDS that servers return some appropriate value (e.g. the RECOMMENDS that servers return some appropriate value (e.g., the
amount of free disc space). A client cannot entirely assume that amount of free disk space). A client cannot entirely assume that
there is no quota enforced on a resource that does not have this there is no quota enforced on a resource that does not have this
property, but might as well act as if there is no quota. property, but might as well act as if there is no quota.
The value of this property is protected (see section 1.4.2 of The value of this property is protected (see Section 1.4.2 of
[RFC3253] for the definition of protected properties). A 403 [RFC3253] for the definition of protected properties). A 403
Forbidden response is RECOMMENDED for attempts to write a protected Forbidden response is RECOMMENDED for attempts to write a protected
property, and the server SHOULD include an XML error body as defined property, and the server SHOULD include an XML error body as defined
by DeltaV [RFC3253] with the <DAV:cannot-modify-protected-property/> by DeltaV [RFC3253] with the <DAV:cannot-modify-protected-property/>
precondition tag. precondition tag.
4. DAV:quota-used-bytes 4. DAV:quota-used-bytes
Name: quota-used-bytes Name: quota-used-bytes
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The DAV:quota-used-bytes value is the value in octets representing The DAV:quota-used-bytes value is the value in octets representing
the amount of space used by this resource and possibly a number of the amount of space used by this resource and possibly a number of
other similar resources, where the set of "similar" meets at least other similar resources, where the set of "similar" meets at least
the criterion that allocating space to any resource in the set will the criterion that allocating space to any resource in the set will
count against the DAV:quota-available-bytes. It MUST include the count against the DAV:quota-available-bytes. It MUST include the
total count including usage derived from sub-resources if total count including usage derived from sub-resources if
appropriate. It SHOULD include metadata storage size if metadata appropriate. It SHOULD include metadata storage size if metadata
storage is counted against the DAV:quota-available-bytes. storage is counted against the DAV:quota-available-bytes.
Note that there may be a number of distinct but overlapping sets of Note that there may be a number of distinct but overlapping sets of
resources for which a DAV:quota-used-bytes is maintained (e.g. "all resources for which a DAV:quota-used-bytes is maintained (e.g., "all
files with a given owner", "all files with a given group owner", files with a given owner", "all files with a given group owner",
etc.). The server is at liberty to choose any of those sets but etc.). The server is at liberty to choose any of those sets but
SHOULD do so in a repeatable way. The rule may be configured per SHOULD do so in a repeatable way. The rule may be configured per
repository. repository.
Support for this property is REQUIRED on collections, and OPTIONAL on Support for this property is REQUIRED on collections, and OPTIONAL on
other resources. A server SHOULD implement this property for each other resources. A server SHOULD implement this property for each
resource that has the DAV:quota-available-bytes property. resource that has the DAV:quota-available-bytes property.
This value of this property is computed (see Section 1.4.3 of This value of this property is computed (see Section 1.4.3 of
[RFC3253] for the definition of computed property). A 403 Forbidden [RFC3253] for the definition of computed property). A 403 Forbidden
response is RECOMMENDED for attempts to write a protected property, response is RECOMMENDED for attempts to write a protected property,
and the server SHOULD include an XML error body as defined by DeltaV and the server SHOULD include an XML error body as defined by DeltaV
[RFC3253] with the <DAV:cannot-modify-protected-property/> [RFC3253] with the <DAV:cannot-modify-protected-property/>
precondition tag. precondition tag.
5. Example PROPFIND request and response 5. Example PROPFIND Request and Response
Request: Request:
PROPFIND /~milele/public/ HTTP/1.1 PROPFIND /~milele/public/ HTTP/1.1
Depth: 0 Depth: 0
Host: www.example.com Host: www.example.com
Content-Type: text/xml Content-Type: text/xml
Content-Length: xxx Content-Length: xxx
<?xml version="1.0" ?> <?xml version="1.0" ?>
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<D:propstat> <D:propstat>
<D:prop> <D:prop>
<D:quota-available-bytes>596650</D:quota-available-bytes> <D:quota-available-bytes>596650</D:quota-available-bytes>
<D:quota-used-bytes>403350</D:quota-used-bytes> <D:quota-used-bytes>403350</D:quota-used-bytes>
</D:prop> </D:prop>
<D:status>HTTP/1.1 200 OK</D:status> <D:status>HTTP/1.1 200 OK</D:status>
</D:propstat> </D:propstat>
</D:response> </D:response>
</D:multistatus> </D:multistatus>
6. Error reporting 6. Error Reporting
WebDAV [RFC2518] defines the status code 507 (Insufficient Storage). WebDAV [RFC2518] defines the status code 507 (Insufficient Storage).
This status code SHOULD be used when a client request (e.g. a PUT, This status code SHOULD be used when a client request (e.g., a PUT,
PROPFIND, MKCOL, MOVE or COPY) fails because it would exceed their PROPFIND, MKCOL, MOVE, or COPY) fails because it would exceed their
quota or physical storage limits. In order to differentiate the quota or physical storage limits. In order to differentiate the
response from other storage problems, the server SHOULD include an response from other storage problems, the server SHOULD include an
XML error body as defined by DeltaV [RFC3253] with the appropriate XML error body as defined by DeltaV [RFC3253] with the appropriate
precondition tag. precondition tag.
Preconditions: Preconditions:
(DAV:quota-not-exceeded): the allocated quota MUST NOT be exceeded by (DAV:quota-not-exceeded): the request MUST NOT cause the allocated
the request. quota to be exceeded.
(DAV:sufficient-disk-space): there is sufficient physical space to (DAV:sufficient-disk-space): there is sufficient physical space to
execute the request. execute the request.
Example error response: Example error response:
HTTP/1.1 507 Insufficient Storage HTTP/1.1 507 Insufficient Storage
Content-Length: xxx Content-Length: xxx
Content-Type: text/xml Content-Type: text/xml
<?xml version="1.0"> <?xml version="1.0">
<error xmlns="DAV:"> <error xmlns="DAV:">
<quota-not-exceeded/> <quota-not-exceeded/>
</error> </error>
Implementation note: some client may be be able to take advantage of Implementation note: some clients may be able to take advantage of
the different precondition codes when mapping to operating system the different precondition codes when mapping to operating system
status codes, such as E_NOSPC and E_DQUOT in NFS (see [RFC3530], status codes, such as E_NOSPC and E_DQUOT in NFS (see [RFC3530],
Section 12). Section 12).
7. Notes 7. Notes
Server implementations store and account for their data in many Server implementations store and account for their data in many
different ways. Some of the challenges: different ways. Some of the challenges:
o Some server implementations find it prohibitive to count storage o Some server implementations find it prohibitive to count storage
used for metadata, others may choose to do so for better used for metadata; others may choose to do so for better
accounting. accounting.
o Older versions of resources may be stored as well. o Older versions of resources may be stored as well.
o Variants of one resource may exist with different content lengths. o Variants of one resource may exist with different content lengths.
o Content may be dynamically generated. o Content may be dynamically generated.
o Resource bodies can be compressed. o Resource bodies can be compressed.
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of storage as indicated by the DAV:getcontentlength property of storage as indicated by the DAV:getcontentlength property
defined in [RFC2518] for the resource. If deleting a resource defined in [RFC2518] for the resource. If deleting a resource
does not free up any space, the file may have been moved to a does not free up any space, the file may have been moved to a
"trash" folder or "recycle bin", or retained as in versioning "trash" folder or "recycle bin", or retained as in versioning
systems ([RFC3253]). systems ([RFC3253]).
o Since there are many factors that affect the storage used by a set o Since there are many factors that affect the storage used by a set
of resources, including automatic compression, the size of of resources, including automatic compression, the size of
associated metadata, and server-inserted content (such as that associated metadata, and server-inserted content (such as that
created by PHP code) in the on-the-wire representation of created by PHP code) in the on-the-wire representation of
resources, clients are advised to not depend on the value of DAV: resources, clients are advised not to depend on the value of DAV:
quota-used-bytes being the sum of the DAV:getcontentlength quota-used-bytes being the sum of the DAV:getcontentlength
properties for resources contained by a collection. properties for resources contained by a collection.
o Additionally, because there may be a number of distinct but o Additionally, because there may be a number of distinct but
overlapping sets of resources for which a DAV:quota-used-bytes is overlapping sets of resources for which a DAV:quota-used-bytes is
maintained (Section 4), there may be no correlation between the maintained (Section 4), there may be no correlation between the
size of the resources in a collection and DAV:quota-used-bytes. size of the resources in a collection and DAV:quota-used-bytes.
For example a server that implements user-based quotas, DAV:quota- For example, for a server that implements user-based quotas,
used-bytes usually will be the same for a collection and it's DAV:quota-used-bytes usually will be the same for a collection and
members. its members.
o On some systems where quota is counted by collection and not by o On some systems where quota is counted by collection and not by
user, a quota on a sub-collection may be larger than the quota on user, a quota on a sub-collection may be larger than the quota on
the parent collection that contains it. For example, the quota on the parent collection that contains it. For example, the quota on
/~milele/ may be 100 MB, but the quota on /~milele/public/ may be /~milele/ may be 100 MB, but the quota on /~milele/public/ may be
unlimited. This allows the space used by /~milele/public/ to be unlimited. This allows the space used by /~milele/public/ to be
as large as the quota on /~milele/ allows (depending on the other as large as the quota on /~milele/ allows (depending on the other
contents of /~milele/) even if the quota on /~milele/ is changed. contents of /~milele/) even if the quota on /~milele/ is changed.
Thus, even when the quota on a parent collection is changed, it is Thus, even when the quota on a parent collection is changed, it is
not necessarily required to change the quota on every child or not necessarily required to change the quota on every child or
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A hacker may prefer to store files in collections with a large quota. A hacker may prefer to store files in collections with a large quota.
This isn't strictly a security concern because it doesn't make it any This isn't strictly a security concern because it doesn't make it any
easier to store files. On the other hand, the DAV:quota-used-bytes easier to store files. On the other hand, the DAV:quota-used-bytes
property may make it easier to detect tampering or misuse. property may make it easier to detect tampering or misuse.
9. Internationalization Considerations 9. Internationalization Considerations
Quota is counted in Arabic numerals expressed in strings. There are Quota is counted in Arabic numerals expressed in strings. There are
no internationalization considerations. no internationalization considerations.
10. IANA Considerations 10. Acknowledgements
There are no IANA considerations.
11. Acknowledgements
Stefan Eissing, Geoff Clemm, Jim Luther, Julian Reschke, Jim Stefan Eissing, Geoff Clemm, Jim Luther, Julian Reschke, and Jim
Whitehead, among others, have provided valuable comments on this Whitehead, among others, have provided valuable comments on this
document. document.
12. References 11. References
12.1 Normative References 11.1. Normative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997. Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2518] Goland, Y., Whitehead, E., Faizi, A., Carter, S., and D. [RFC2518] Goland, Y., Whitehead, E., Faizi, A., Carter, S., and D.
Jensen, "HTTP Extensions for Distributed Authoring -- Jensen, "HTTP Extensions for Distributed Authoring --
WebDAV", RFC 2518, February 1999. WebDAV", RFC 2518, February 1999.
[RFC3253] Clemm, G., Amsden, J., Ellison, T., Kaler, C., and J. [RFC3253] Clemm, G., Amsden, J., Ellison, T., Kaler, C., and J.
Whitehead, "Versioning Extensions to WebDAV (Web Whitehead, "Versioning Extensions to WebDAV (Web
Distributed Authoring and Versioning)", RFC 3253, Distributed Authoring and Versioning)", RFC 3253, March
March 2002. 2002.
12.2 Informative References 11.2. Informative References
[RFC3530] Shepler, S., Callaghan, B., Robinson, D., Thurlow, R., [RFC3530] Shepler, S., Callaghan, B., Robinson, D., Thurlow, R.,
Beame, C., Eisler, M., and D. Noveck, "Network File System Beame, C., Eisler, M., and D. Noveck, "Network File System
(NFS) version 4 Protocol", RFC 3530, April 2003. (NFS) version 4 Protocol", RFC 3530, April 2003.
Authors' Addresses Authors' Addresses
Brian Korver Brian Korver
Network Resonance, Inc. Network Resonance, Inc.
2483 E. Bayshore Road 2483 E. Bayshore Road
Suite 212 Suite 212
Palo Alto, CA 94303 Palo Alto, CA 94303
US US
Phone: +1 415 812-7705 Phone: +1 650 812-7705
Email: briank@networkresonance.com EMail: briank@networkresonance.com
Lisa Dusseault Lisa Dusseault
Open Source Applications Foundation Open Source Applications Foundation
543 Howard Street 543 Howard Street
5th Floor 5th Floor
San Francisco, CA 94105 San Francisco, CA 94105
US US
Phone: +1 415 946-3040 Phone: +1 415 946-3040
Email: lisa@osafoundation.org EMail: lisa@osafoundation.org
Intellectual Property Statement Full Copyright Statement
Copyright (C) The Internet Society (2006).
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 The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed to Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in pertain to the implementation or use of the technology described in
this document or the extent to which any license under such rights 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 might or might not be available; nor does it represent that it has
made any independent effort to identify any such rights. Information made any independent effort to identify any such rights. Information
on the procedures with respect to rights in RFC documents can be on the procedures with respect to rights in RFC documents can be
found in BCP 78 and BCP 79. found in BCP 78 and BCP 79.
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such proprietary rights by implementers or users of this such proprietary rights by implementers or users of this
specification can be obtained from the IETF on-line IPR repository at specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr. http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary copyrights, patents or patent applications, or other proprietary
rights that may cover technology that may be required to implement rights that may cover technology that may be required to implement
this standard. Please address the information to the IETF at this standard. Please address the information to the IETF at
ietf-ipr@ietf.org. ietf-ipr@ietf.org.
Disclaimer of Validity Acknowledgement
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.
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.
Acknowledgment
Funding for the RFC Editor function is currently provided by the Funding for the RFC Editor function is provided by the IETF
Internet Society. Administrative Support Activity (IASA).
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