2.4.2 Control And Provisioning of Wireless Access Points (capwap)

NOTE: This charter is a snapshot of the 67th IETF Meeting in San Diego, California USA. It may now be out-of-date.

Last Modified: 2006-07-17


Margaret Wasserman <margaret@thingmagic.com>
Mahalingam Mani <mmani@avaya.com>
Dorothy Gellert <dorothy.gellert@nokia.com>

Operations and Management Area Director(s):

Dan Romascanu <dromasca@avaya.com>
David Kessens <david.kessens@nokia.com>

Operations and Management Area Advisor:

Dan Romascanu <dromasca@avaya.com>

Technical Advisor(s):

Scott Kelly <skelly@arubanetworks.com>
Bob O'Hara <bohara@airespace.com>
Charles Clancy <clancy@ltsnet.net>

Mailing Lists:

General Discussion: capwap@frascone.com
To Subscribe: http://lists.frascone.com/mailman/listinfo/capwap
Archive: http://lists.frascone.com/pipermail/capwap

Description of Working Group:

The original CAPWAP WG charter included drafting a problem statement
and a taxonomy of architectures. The new charter of the CAPWAP WG
proposes building upon the original charter and developing a CAPWAP
protocol to provide interoperability among WLAN backend architectures.
The intent of the CAPWAP protocol is to facilitate control, management
and provisioning of WLAN Termination Points (WTPs) specifying the
services, functions and resources relating to 802.11 WLAN Termination
Points in order to allow for interoperable implementations of WTPs
and ACs.

The revised CAPWAP WG will reference two classes of the Centralized
WLAN Architecture family, namely the Local MAC and the Split MAC,
as described in the CAPWAP Architecture Taxonomy draft. The protocol
will define the CAPWAP control plane including the primitives to
control data access. An effective Centralized CAPWAP Architecture
impacts how WLAN data traffic is managed over the backend network.
This implies the abilitiy to control how data is forwarded by
negotiating existng data encapsulation mechanisms and specifying
data payload formats in order to ensure interoperability between
CAPWAP vendors. No other specifications of the CAPWAP data plane
are within the scope of this charter.

The CAPWAP WG will strive for extensibility in the protocol design
to favor future applicability to other access technologies, especially
IEEE 802.16. While accommodation of any access technology other than
IEEE 802.11 is not required for successful completion, there are clear
deployment advantages if a wide range of access technologies are

In summary, the primary goals of the group will be:

1. Defining a set of Objectives based on the architecture taxonomy
work that lists the requirements for an interoperable CAPWAP
protocol. In addition, the WG will incorporate requirements
derived from the inputs provided by Enterprise and (hotspot)
Providers based on the WLAN deployment challenges addressed
by CAPWAP architecture. This document will:

a. include objectives to address problems described in the
CAPWAP Problem statement document
b. Describe each objective, its benefit to the protocol and
how it satisfies the problem statement.
c. Prioritize and classify the objectives into 3 categories:
i. Mandatory and Accepted
ii. Desirable
iii. Rejected
d. Undergo review in IEEE 802 as needed

This should result in the first WG Last Call for Objectives draft.

To avoid requirements bloat and stalemate, the WG has a
hard deadline on the Objectives phase. The WG MUST reach WG
consensus on the objectives draft by Feb 2005. This is for
several reasons:
* We must send this for review to IEEE at that time.
* We must have a reasonably stable set of objectives
so that candidate submissions are aware of the objectives
to be met.

The 2nd WG Last Call (in April) for the objectives draft is to
ensure that the WG has consensus on any changes that may result
from IEEE and expert review. So it is not the intention that
the WG keeps adding new Objectives after Feb 2005.

If the WG cannot reach consensus on the Objectives draft by the
May 2005 milestone to the IESG, the WG will close.

2. Evaluating a set of candidate proposals that include existing
IETF protocols and any proposals leading to the selection of
a protocol on which to base the CAPWAP standard.

3. Developing a CAPWAP protocol standard that meets the Mandatory
and Accepted objectives from the Evaluation draft and contains
the minimal set of feature needed to control and provision
WLAN Access Points. Specifically The CAPWAP protocol document
will address the following considerations:
a. Architecture
b. Operations
c. Security
d. Network Management
e. Scalability
f. Performance

4. A MIB Document to support the CAPWAP protocol.

In addition, the CAPWAP WG will maintain its Liaison with the
IEEE to ensure consistency of its work with the IEEE 802.11

* Objectives/Criteria Document for CAPWAP protocol
* Protocol evaluation and base protocol selection document
* CAPWAP Protocol standard
* MIB support standard

Goals and Milestones:

Done  Last call for problem statement draft.
Done  Discuss last call comments for problem statement at IETF 59.
Done  Last Call for architecture description document.
Done  Submit problem statement to IESG for publication approval.
Done  Architecture document to expert review.
Done  Stable Architecture document for review/sync-up with IEEE 802
Done  Discuss results of IEEE 802 review/sync-up
Done  Issue first Internet-Draft of CAPWAP Objectives document
Done  Submit CAPWAP Objectives to IEEE/IETF experts review
Done  First WGLC for CAPWAP Objectives Draft
Done  Deadline to submit candidate protocol proposals to the WG
Done  Second WGLC for CAPWAP Objectives Draft
Done  Issue first Internet-Draft of CAPWAP Evaluation draft
Done  Submit CAPWAP Evaluation draft to IESG as Information RFC
Done  Submit CAPWAP Objectives draft to IESG as Informational RFC
Done  Issue first Internet Draft of CAPWAP protocol
Jul 2006  Issue first Internet-Draft of CAPWAP MIB
Aug 2006  WGLC for CAPWAP protocol
Sep 2006  Submit CAPWAP protocol to IESG as Proposed Standard RFC
Sep 2006  WGLC for CAPWAP MIB
Sep 2006  Submit CAPWAP MIB to IESG as Proposed Standard RFC


  • draft-narasimhan-ietf-slapp-01.txt
  • draft-ietf-capwap-protocol-specification-03.txt
  • draft-ietf-capwap-protocol-binding-ieee80211-00.txt

    Request For Comments:

    RFC3990 I CAPWAP Problem Statement
    RFC4118 I Architecture Taxonomy for Control and Provisioning of Wireless Access Points(CAPWAP)
    RFC4564 I Objectives for Control and Provisioning of Wireless Access Points (CAPWAP)
    RFC4565 I Evaluation of Candidate Control and Provisioning of Wireless Access Points (CAPWAP) Protocols

    Meeting Minutes


    CAPWAP WG: Milestones & other Summary
    CAPWAP Editors' Report
    Protocol & Bindings: Various Header Issues
    CAPWAP Issues: KeyRSC (43)
    CAPWAP Issues: QoS (#196, #212,# 214 & others)
    CAPWAP Protocol & Bindings: DTLS & CAPWAP interactions
    CAPWAP Threat Analysis Draft:: Scott Kelly & Charles Clancy