Subject: [Capwap] Taxonomy Survey Response: Nortel Networks WMN

From: Kue Wong <[email-masked]>
Date: Thu, 17 Jun 2004 16:59:12 -0400

Following survey response posted to capwap list on behalf of Kevin Dick
by Kue Wong.

---------------------------------------------------------------------------

Kevin Dick [[email-masked]]

taxonomy responses for Nortel Networks Wireless Mesh Networks (WMN) product

======> CAPWAP Survey Responses

(1) Design considerations & requirements: please briefly describe your
design principles for this architecture.

Response:
The design principles for Nortel’s Wireless Mesh Network product are as
follows:

- enables WLAN deployment and simplified coverage for open areas both
indoor and outdoor, - brings “hotspots” together into a Community
Area Network (CAN) providing larger coverage area and mobility, -
eliminates the need for extensive Ethernet cabling or leased lines
through use of wireless links between access points in a mesh
configuration,

- provides auto-configuration and centralized management capabilities to
simplify network operations, - avoids service outages by providing
efficient routing using auto-discovery and self-healing algorithms,
- provides a highly secure environment for both end users and the
network, - scaleable architecture from small enterprise to a large
community network, - compliant to existing 802.11 standard protocols
and interfaces to ensure universal 802.11 client access, -
conformance to FCC requirements on 802.11 indoor and outdoor
deployment.

(2) WLAN functions supported: Please list the functions supported in
this WLAN briefly, but please do not send us the entire data sheet.
Examples of WLAN functions includes the STA services, Distributed
System Services (as defined by 802.11), radio resource management
and control, AP load balancing, mobility support, WLAN network wide
security functions (including authentication, encryption for privacy
and integrity, etc.) and any others not listed here but deemed
important in your design.

Response:
Supported WLAN functions are:

- the STA services open system authentication WPA with TTLS and PEAP
support web portal redirect deauthentication

- the Distribution System Services (as defined by 802.11) association
disassociation distribution and integration services reassociation

- mobility support Session persistent Corporate VPN access

- WLAN network wide security functions (authentication, encryption for
privacy and integrity etc.) fully WPA compliant

(3) The functional architecture to implement the functions described
above: whether it is by autonomous AP architecture, or "split"
architecture. For split architecture, please provide the functional
mapping of WLAN functions onto the AP and AC -- with just enough
details that help us understand the kinds of functional interface
necessary between the two. For distributed architectures, describe
how the functionality is distributed across the nodes in the
network.

Response:
- fully autonomous AP architecture

(4) The protocol used in between AP and AC, for split architecture; or
the protocol used between mesh nodes, for distributed architecture.

Response:
- does not apply

(5) The topological assumptions between AP and AC (is it directly
connected, L2 switched, or L3 routed?) -- this also helps us to
understand the deployment scenarios.

Response:
- does not apply

(6) Security threat analysis: what kinds of threat introduced by the
split architecture, and how that are addressed.

Response:
- does not apply

(7) Pros and Cons of this architecture, esp. in relation to the four
problems described in the CAPWAP problem statement. Please keep the
analysis at technical instead of marketing level.

When referring to the four problems described in CAPWAP, the pros and
cons design considerations are as follows:

CAPWAP Problem Statement#1: The first problem introduced by large WLAN
deployments is that each AP is an IP-addressable device requiring
management, monitoring, and control.

Response:
The advantage of Nortel's architecture over legacy IP network
infrastructure deployment is avoiding global IP addressing. This is
supported by Intranet and Extranet private IP addressing across
system components and users access through the DHCP server. This
eliminates the need for global IP addressing for system
administration.

CAPWAP Problem Statement#2: A second problem introduced by large WLAN
deployments is distributing and maintaining a consistent
configuration throughout the entire set of access points in the
WLAN. Access point configuration consists of both long-term static
information, such as addressing and hardware settings, and more
dynamic provisioning information, such as individual WLAN settings
and security parameters. Large WLAN installations that need to
update dyanmic provisioning information in all the APs in the WLAN
require a prolonged phase-over time, while each AP is updated and
the WLAN does not have a single, consistent, configuration.

Response:
The basic design requirement is to support in-service upgrade with
downloadable configuration capabilities.

CAPWAP Problem Statement#3:
A third problem introduced by large WLAN deployments is the
difficulty in dealing effectively with the dynamic nature of the
WLAN medium, itself. Due to the shared nature of the wireless
medium, shared with APs in the same WLAN, with APs in other WLANs,
and with devices that are not APs at all, parameters controlling the
wireless medium on each AP must be monitored frequently and modified
in a coordinated fashion to maximize performance for the WLAN to
utilize the wireless medium efficiently. This must be coordinated
among all the access points, to minimize the interference of one
access point with its neighbors. Manually monitoring these metrics
and determining a new, optimum configuration for the parameters
related to the wireless medium is a task that takes a significant
amount of time and effort.

Response:
Nortel's implementation includes automated configuration and centralized
management capabilities to simplify network operations.

In addition auto-discovery and self-healing algorithms are used.

CAPWAP Problem Statement#4: A fourth problem introduced by large WLAN
deployments is securing access to the network and preventing
installation of unauthorized access points. Access points are often
difficult to physically secure, since their location must often be
outside of a locked network closet or server room. Theft of an
access point, with its embedded secrets, allows the thief to obtain
access to the resources secured by those secrets. Recently, multiple
vendors have begun offering proprietary solutions Calhoun, et al.

Response:
Nortel's solution provides a highly secure environment for both end
users and the network including safe-guards against access and
misuse of embedded information. Mechanisms include WPA-equivalent
authorization, key management, automatic key refresh and encryption
to protect user, control and management data. Techniques are
embedded in the auto-discovery algorithm to prevent rogue AP
intrusions to the NW.

_______________________________________________
Capwap mailing list
[email-masked]
http://mail.frascone.com/mailman/listinfo/capwap