Then look at costs, going beyond the sticker price to see what the vendor charges for a support contract. And if the answers aren't enough to trigger a purchase, net managers can build their own caches, using freeware like Squid. Proxy caches run caching and other functions in software on general-purpose platforms. Caching appliances typically comprise caching software running on a dedicated hardware platform. And hardware makes for faster caching, as even some proxy server vendors admit.
Users also cite the significance of speed.
Loskot had been using the Netscape product but switched after users complained about response times. In theory, it would be possible for a corporate networker to build a proxy server that offers as much in the way of performance as a cache appliance. But it would require the purchase of extremely expensive multiprocessing server hardware. And in practice, that's not how net managers are deploying proxy server caches, vendors and users say. That's the basic difference between product types.