Microsoft Windows Update and Network Bandwidth?

Brett Glass asks: "As we reviewed the cache statistics for our small ISP today, we noted that the traffic generated by Microsoft's Windows Update feature constituted 45% -- no, that's not a misprint -- of our total throughput. Because so many computers on the Internet run Windows, this massive resource drain occurs whenever Microsoft announces major security holes (as it did this week). The traffic could be greatly reduced, and service to users much improved, if the updates were cacheable at the ISP. But Microsoft has set up the service in such a way that the data can't be cached. (It's digitally signed, so inserting Trojans into the cache is virtually impossible; in any event, no more of an issue than intercepting the data stream.) Are others out there seeing the same pattern? How might Microsoft be convinced to make its updates cacheable, so as not to waste unthinkable amounts of bandwidth?"

Comments

Re:can't be cached?

[PerryMason]

My experience is that if you download a single update, such as the Media Player, IE, service packs etc, which can only be downloaded individually, then squid will cache it. If you select a few updates, such as grouping your critical updates, it wont do it.

Looking at my squid logs, it appeared that there was a problem with WindowsUpdate issuing a 0 byte sized reply to the GET request (must be somthing to do with the activex control I guess, but never really bothered to look further into it). Squid seemed to choke on the 0 byte reply and obviously didnt cache the rest of the download.

Interestingly enough, MS's caching offering ISA appears to deal with it, but I suppose that they specifally coded it with a knowledge of how their activex control works and hence it knows whats following that 0 byte reply.

Disclaimer - I checked this all out when the new WindowsUpdate first came out and havent been arsed to look at it since then. I ended up just setting up a shitty old box as a SUS server and going that route. (The only benefit to being an MSDN partner being $0 cost for licensing as I justify it as being for testing purposes ;)