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Vista Bug Costs Users In Swedish Town Their Internet
Lund, Sweden refuses to work around a Vista bug, so people who live there must choose between Vista and internet access. It's nice to see the right people being held accountable for a change.
The bug in Vista is that it sends somewhat broken DHCP requests that Lund Energi's DHCP server refuses to reply to. If you have a home router the DHCP server in the router would (propably) reply to the requests from Vista and other computers on your LAN. And the router sends correct DHCP requests to Lund Energi's server in order to get it's own public IP address.
In short, having a home router would solve the problem.
Both of the english articles listed in this slashdot-post says that Lundis Energi has no desire to do anything. However, in a Swedish newspaper http://www.metro.se/se/article/2007/08/28/14/2423- 48/index.xml they say:
"Our technicians are looking in the matter to see what we can do but it is mainly up to Microsoft to fix this issue" /Åsa Holmander, product manager at Lundis Energi (rough translation)
From : http://www.dhcp-handbook.com/dhcp_faq.html#wisrb
"Which implementations support or require the broadcast flag?
The broadcast flag is an optional element of DHCP, but a client which sets it works only with a server or relay that supports it.
Clients
Microsoft Windows NT
DHCP client support added with version 3.5 sets the broadcast flag. Version 3.51 and later no longer set it. The exception is in the remote access support: it sets the flag when it uses DHCP to acquire addresses to hand out to its PPP clients.
tcp/ip-32 for Microsoft Windows for Workgroups (WFW)
Version 3.11a sets it, but version 3.11B doesn't.
Microsoft Windows 95
Does not set the broadcast flag."
So, I guess Vista only works with Servers that support it and it was an option to implemant it. End of Story.
"Enjoy what you're doing! If it becomes drudgery, you're doing it wrong!" - Jim Butterfield
Vista is only compliant to the RFCs if it is legacy code :-)
RFC 1542 sayeth
3.1.1 The BROADCAST flag [...] This addition to the protocol is a workaround for old host implementations. Such implementations SHOULD be modified so that they may receive unicast BOOTREPLY messages, thus making use of this workaround unnecessary. In general, the use of this mechanism is discouraged.
RESOLUTION
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall your operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
To resolve this issue, disable the DHCP BROADCAST flag in Windows Vista. To do this, follow these steps:
1. Click StartStart button, type regedit in the Start Search box, and then click regedit in the Programs list.
User Account Control permission If you are prompted for an administrator password or for confirmation, type your password, or click Continue.
2. Locate and then click the following registry subkey:c es\Tcpip\Parameters\Interfaces\{GUID}
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Servi
In this registry path, click the (GUID) subkey that corresponds to the network adapter that is connected to the network.
3. On the Edit menu, point to New, and then click DWORD (32-bit) Value.
4. In the New Value #1 box, type DhcpConnDisableBcastFlagToggle, and then press ENTER.
5. Right-click DhcpConnDisableBcastFlagToggle, and then click Modify.
6. In the Value data box, type 1, and then click OK.
7. Close Registry Editor.
So Vista isn't (formally) going counter to protocol, it's just going counter to a 15-year old custom. Nonetheless, Vista *can* cooperate, it just needs to be told not to raise the DHCP BROADCAST flag. And yes, that route goes via a registry modification.
In summary: a tropical storm in a teacup.
Right people here are discussing RCFs and wonder what is going on, well I live in Lund and here is my take on what has happened:
a)Per the RFC servers do not need to implement the broadcast flag, but it is a good idea if you want to support systems that use it.
b)Per RFC Vista doesn't need to clear the broadcast bit, but it is strongly recommended and setting it is intended for legacy clients only.
c)Lund's energi's network doesn't support the broadcast and thus Vista machines do not get an IP over DHCP since they set the broadcast bit.
d)For reasons we don't yet know, Lund energi won't implement a workaround on their server. I don't know enough about DHCP or their systems to tell why, so I guess there might be a technical issue or perhaps they are just being jerks.
e)The fix is to set a registry key, which is easy for technical users, but a pain for those who don't know about it.
My judgement is that Lund's energi has a shitty DHCP server and Vista is a shitty DHCP client. Since the fix is so simple ( adding a registry key ) this really ought to be a non-issue, but because Microsoft and Lund's energi are both incompetent crappy companies the end user is left with a problem that would actually be rather easy to resolve. Those in the know can work around it, but non-technical users are left without service while those responsible point the finger at one another. The sad thing is that this really isn't particularly surprising. Hmm, did I forget something? Oh yea, the article summary is wrong since there are scores of ISPs in Lund, and this only affects one of them. So yea, I'm not very surprised at all...
My company ran into this as well. We have 4000 wireless customers spread out on 20+ antennas (each with its own Cisco switch). We're a Microsoft partner so we contacted them about the problem right away.
As I understood it, the bug was this: Vista will only accept broadcast replies to DHCP requests. Any multicast response is discarded for security reasons (!?). So their solution was to put a DHCP server on every level of our network (for us, one for every 200 users) or switch to a network that relayed the broadcasted replies (ie: hubs). They also told us it wasn't a bug so they wouldn't issue a patch to correct it. There was a KB article on the issue but when we had users call MS support and ask them to walk them through applying it, we got a bunch of angry calls back to us saying MS refused to help them with it. We also talked to Cisco a bit to see if they had any idea what we could do to relay the broadcast but they never got us a solution.
So in the end, we told MS that we'd either need a better way to fix this or we'd just tell our users not to use Vista. They seemed okay with us telling users not to use it so we have. A few of our users still use Vista with a home router and that seems to work alright. Luckily, there aren't too many Vista users yet and when faced with the option of buying and configuring a router or buying and configuring Windows XP, they've decided on XP. So all in all, it wasn't that big of a deal.
Jem Tallon
Funny, out of the box XP SP2 doesn't support my NIC, graphics card (Well only in VGA mode) or my USB printer. My network and chipset driver is a 40MB download, my GPU driver, 50MB, and my printer drivers a pleasant 180MB. Oh and then I have to update DirectX, update Windows Messenger, update to IE7, update to WMP 11 and then get going on the 80 or so other updates (which comes in at almost 50-100 MiB I suspect) from Windows Update.
Out of box Ubuntu supports my network card and with a few simple clicks my printer and I can start installing my favourite software.
My point here isn't to start a flame war, but rather that the Window's experience isn't so wonderful out of the box when the last service pack was 3 years before your current hardware came out. When you consider this, there is something to be said for Ubuntu's 6 month cycle.
Oh and I've never used a wireless adapter in XP (~6) or Vista (1) that worked out the box.
I think you're missing the point.
I work for a networking company and a few months ago I fixed our BootP relay to be able to handle this.
If you read the DHCP RFC, you will discover that this broadcast packet is actually an optional part of the spec. Furthermore, it was designed for (at the time - circa 1993) LEGACY equipment that could not handle unicast responses.
Ie, I ask for an IP address, and because I'm a crappy old piece of hardware that can't handle it, I want the DHCP server to reply to me with a broadcast reply telling me my IP address. Normally such responce is unicast to your MAC address and everyone is happy.
Windows XP works fine and will accept a unicast reply. In Vista Microsoft had the brilliant idea that they should enable this flag by default - despite the fact that any modern computer should be able to handle a unicast reply - they could back in 1993 after all.
So yes, the fault is precisely with Microsoft for enabling an unnecessary and OPTIONAL part of the DHCP protocol by default, causing untold problems that could simply be avoided if they stuck to the XP way of doing things.