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It is important--not just to Cisco, but to the entire industry--that standards prevail, particularly in a global market such as wireless networking. -- Bob O'Hara (Cisco Systems)

http://www.networkcomputing.com/channels/wireless/showArticle.jhtml?queryText=&articleID=195900045&pgno=2

This is the same reason why The CWNP Program has been working hard to tightly align our exams, practice exams, courseware, and study guides with the IEEE 802.11 standard (as amended).

Devinator

Thankyou for the reference to a most interesting article.

What interests me is whether Meru's assertion that they are completely standards compliant is correct or not.

What do you think?

I find it interesting that only Bob O-Hara was quoted, not Vaduvur Bharghavan. They seem to both be presenting standards compliance as paramount ?!?!

MM

This is the most entertaining technical article I've ever read. I've never encountered one which is so transparent as to the behind-the-scenes machinations of these events.

My favourite quotes
"Meru's equivalent of the formula for Coca-Cola"
"Cisco's reply surprised us: Rather than spinning the results"
"slow response, attributing it to a broken laptop the prevented him from connecting to the company's VPN." scary Company vulnerability! Backups? Ghost should allow recovery in 1 hour.

"we don't know first- or even second-hand how well this works."

Comments on vendor replies...
- Cisco -
Cisco strongy imply Meru have violated 802.11 standard(s) with out a convincing explanation as to where & how.
It would have been convincing if he said "The standard says this for Duration <m>, Meru do this <n>. Because <m> is less than <n> Meru are deemed to have violated 802.11." The technical level of his response doesn't assume much 802.11 knowledge so it should not assume reader knowledge of <m>.

"The hundreds of members of the 802.11 working group have toiled for more than 15 years to create a standard that uses a well-understood mechanism for fairly sharing the limited resource of the unlicensed radio band."
- I happened to be listening to violin music when I read this ... it seemed appropriate.

Wouldn't it be funny if Cisco changed some details of their media access as a results of this test !!! :)

"Cisco has developed (highly utilized) planning tools embedded within our Wireless Control System software"
- Cisco wireless people told me WCS planning tool is only useful for creating pretty pictures for management. Maybe they

just don't know how to drive it. They certainly could not present it convincingly to me.

"In fact, these algorithms could make the Cisco WLAN network a better
neighbor because our systems try to avoid being an interferer to other networks."
- DOS vulnerability of Cisco system? The default timers potentially change channel & Tx powerer every 10 minutes. What effect does this have on clients?

"In no case do our innovations violate other vendors' systems' ability to operate in the shared spectrum."
- this sticks out as a carefully worded statement.
- if standards are open enough to interpretation (which I think is common) 2 different valid interpretations might trip over each other.

- Meru -
"We believe the Network Computing tests provide incontrovertible evidence that only one vendor, Meru Networks, can support high client densities, enterprise-quality voice and data, diverse client
populations and efficient 802.11b/g performance."
- remind me how many vendors were in the test ... 2, not the whole market!

"We have many customers that speak on our behalf about their
experiences with Meru products."
- trust me I'm a vendor :)

Are the vendors arguing over "what most vendors do" or the standard?

"the allegation of Meru inflating the duration
fields in its frames to gain unfair access to the channel is false."
- justify this with specific reference to the 2500uS figure stated in the original article and to the typical value of 300uS, then this assertion might be convincing.

"Not once in the entire
bake-off process have the Network Computing authors or our competitors ever identified any specific
section or page or article of the standard that we violate."
- I think Meru have a point - this is what I was looking for rather than the following from the original article,
"The 802.11 standard defines the
CTS-to-Self duration value as being long enough to cover one following data
frame (often in the range of 300 microseconds)"
- Tell the unwashed masses (me) exactly what wording the standards use that this violates.

"They believe the only way
achieve these benefits is to bend the standard, violate it, twiddle parameters outside the rules and so
on."
- no evidence for this stated. Is there any more to this statement than emotion?

"APs remain as independent islands of RF"
- seems to be a misrepresentation of the Cisco system to me.

"Our products are Wi-Fi certified, almost all our customers have legacy access points that interoperate
perfectly with Meru, and Network Computing's tests were performed with standard clients. "
- one unfortunate characteristic of these customers is their inaccessibility :)

"Meru trounced Cisco in the head-to-head tests. End of story."
- a trounce is a little known technical term for any Duration field value > life span of an elephant :) (rushes off to make covert supporting Wikipedia entry)

MM

Hi markh1289,

This is a great post. :-) You had me laughing. Thanks for your thoughts.

Devinator