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DRAFT 5 CRITERIA FOR 802.3 Aggregation of Multiple Link Segments
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5 CRITERIA:

1. Broad Market Potential
* Broad set(s) of applications
* Multiple vendors, multiple users
* Balance cost, LAN vs. attached stations

Many applications and environments will benefit from this capability, in
particular:
- The ability to incrementally scale the bandwidth and increase the
availability of server connections to the network and of switch-to-switch
connections within the network.
- Provide a network upgrade path utilizing existing physical layer
media and the corresponding supported distances as existing 802.3
technology.

Multiple vendors and users have demonstrated interest by attending the
"Trunking and Link Aggregation" tutorial, attending the preliminary study
group meeting, and subscribing to the "stds-802-3-trunking" e-mail
reflector.  Additionally, many vendors have brought products to market that
aggregate parallel 802.3 links into a single logical link in some manner.
??? participants from ??? companies have indicated their support for
creating an interoperable standard.

When link aggregation is used for attaching end-stations to the network,
the cost is balanced between the LAN and the attached station by requiring
a symmetrical number of MACs and physical layer connections at each end of
the aggregated link.

2. Compatibility with IEEE standard 802.3
* Conformance with CSMA/CD MAC, PLS
* Conformance with 802.2
* Conformance with 802 FR

The proposed standard will conform to the CSMA/CD MAC and PLS, with
currently authorized extensions.

The proposed standard will conform to the 802.2 LLC interface.

The proposed standard will conform to the 802 Functional Requirements document.

3. Distinct Identity
* Substantially different from other 802.3 specs / solutions
* Unique solution for problem (not two alternatives / problem)
* Easy for document reader to select relevant spec

The proposed standard is an upgrade for 802.3 users, based upon the 802.3
CSMA/CD MAC.  It differs from other 802.3 specifications and solutions in
that it enables users to operate network connections at bandwidths
incremental to those specified in current 802.3 standards.

The proposed standard will be the only solution achieving linearly
scaleable bandwidth per network connection, while simultaneously providing
high availability and reliability through multiple links.  Additionally,
the proposed standard will achieve this without requiring the development
of a new physical layer.

The proposed standard will be a supplement to the existing 802.3 standard
and will be formatted as a new clause(s) , making it easy for the reader to
select the relevant specification.

4. Technical Feasibility
* Demonstrated feasibility;  reports - working models
* Proven technology, reasonable testing
* Confidence in reliability

Technical feasibility has been demonstrated in widely deployed products
from numerous vendors, which provide link aggregation capabilities similar
to those proposed for this standard.  These capabilities provide a new
operating mode layered upon the existing and well-proven 802.3 MAC and
Physical Layer technologies.  In particular, the proposed standard would
not require the development of a new physical layer or a new physical
medium.

5. Economic Feasibility
* Cost factors known, reliable data
* Reasonable cost for performance expected
* Total installation costs considered

The cost factors for the existing standard can be extrapolated from the
cost of current 802.3 technologies, and will benefit from the "economy of
scale" of the very large installed base and market forecasts for 802.3
technology.

The incremental cost of aggregating multiple links is not expected to be a
significant increase over the sum of the cost of the individual links.
Because the performance increases in proportion to the number of links, the
cost will scale linearly with the performance.

Link aggregation is a very cost effective way of adding bandwidth to a
network installation, because it does not require the adoption and
installation of new Data Link Layer or Physical Layer technologies.