William, Where does caching make sense? Static assets that can be stored on the edge closest to customers ie images, audio, video. These needs are served by your Akamais, IBeams, and Evokes. One other place where it makes sense to cache, in your Corporate environement. There will probably be a flux point for cost savings in respect to bandwidth if a company is able to get the majority of web traffic to remain on the LAN. But in regards to a caching architecture for your web site. Sites that have any revenue tied to advertising will benefit highly from knowing exact demographics, exact visitor counts, etc... In addition advertisers pay more for "targeted advertising" and targeted advertising is done with Dynamic technologies that can not be cached (the banner can be cached and await retrieval). Push technologies are to the advertising industry as napster is to the music industry. Acting as a catalyst in '96, the advertising industry recognized the benefit of targeted advertising that push technologies offer and embraced the internet. There are entire business models built on this principle (pioneers ADFORCE - formerly IMGIS, recent newbies alladvantage, mvalue, etc...). Commerce sites are also dependent on dynamic technology that cannot be cached. Although you will find sites that are entirely static (buy.com & etoys.com) you will generally find that these models are based on volume and that the majority of these sites have never seen a dollar in profit. However the profitable boutique type sites like eStyle.com, are entirely dynamic. Margins are protected by a contractual product line. When you place an order, a query verifies inventory prior to final checkout. In addition, product pages indicate whether items are in stock or not. You cant cache these types of sites. Granted this architecture is hard to scale, but they represent a rare breed of commerce vendors making cash. And by the way saving bandwidth is not justified for the majority of the market. 80% of deployed sites are sucking less than 2Mbps in monthly fees. Most caching implementations will cost way more than the bandwidth costs they avoid. Some dynamic site architectures will benefit from caching if the cache product is able to reduce the number of web servers required in a farm and/or if the cache engine working with the web farm is able to reduce the load on the DB servers. But TTLs will usually have to be set pretty low (2 seconds) in order to do this and the technologies will have to be catered to web development environments (like cacheflow and ASP). Travis Grant System Architect www.kore.com -----Original Message----- From: William Allen Simpson [mailto:wsimpson@greendragon.com] Sent: Friday, October 20, 2000 7:04 AM To: nanog@merit.edu Subject: Re: decreased caching efficiency? Dana Hudes wrote:
I vehemently disagree with the statement that impressions do not make any
sense,
only clickthroughs. There is such a thing as brand awareness, a situation where a banner ad is good for itself even if it doesn't lead to click through.
Of course, in that case, the benefit is to the advertiser. That is, they get the benefit, but you don't get paid. Not my problem. That seems to follow "not make any sense", but YMMV.
It is NOT for YOU to decide what business model makes sense for MY business relationship with MY advertisers.
Nope. You can have any business relationship you'd like. But, by the same token, it is not for *YOU* to decide that *I* have to pay to support YOUR business decision. Last time I looked, there's no constitutional right that guarantees that you can make money.
I pay my ISP to carry IP packets around.
But, you don't pay ME to carry your IP packets around. My customers pay me. I pay my upstream. Therefore, I pay my upstream as little as possible.
In some cases certainly your cache is in fact a copyright violation.
Interesting, if true. Perhaps you could provide a citation? WSimpson@UMich.edu Key fingerprint = 17 40 5E 67 15 6F 31 26 DD 0D B9 9B 6A 15 2C 32