WebDAV Redirector Registry Settings

In Windows Vista and Windows Server 2008 there is an updated WebDAV redirector which has several settings available through registry.

Rober McMurray has documented all currently available settings in his blog, it's a great resource and I have to copy it especially for my own memory.

The base registry hive is:
HKLM\SYSTEM\CurrentControlSet\Services\WebClient\Parameters

The know settings are:

Value & Description	Type	Values	Default
AcceptOfficeAndTahoeServers Specifies whether the WebClient service can connect to web sites that are running SharePoint or Office Web Server.	DWORD	0 = False 1 = True	1
BasicAuthLevel Specifies whether the WebClient service can use basic authentication to talk to a server. Note: Using basic authentication can cause serious security issues as the username/password are transmitted in clear text, therefore the use of basic authentication over WebDAV is disabled by default unless the connection is using SSL. That being said, this registry key can override the default basic authentication behavior, but it is still strongly discouraged.	DWORD	0 = Basic authentication is disabled 1 = Basic authentication is enabled for SSL web sites only 2 = Basic authentication is enabled for SSL and non-SSL web sites	1
FileAttributesLimitInBytes Specifies the maximum size that is allowed by the WebClient service for all properties on a specific collection.	DWORD	Size of attributes in bytes	1,000,000 decimal (1 MB)
FileSizeLimitInBytes Specifies the maximum size in bytes that the WebClient service allows for file transfers.	DWORD	File size in bytes	50,000,000 decimal (50 MB)
InternetServerTimeoutInSec Specifies the connection timeout for the WebClient service uses when communicating with non-local WebDAV servers.	DWORD	Time in seconds	30 decimal
LocalServerTimeoutInSec Specifies the connection timeout for the WebClient service uses when communicating with a local WebDAV server.	DWORD	Time in seconds	15 decimal
SendReceiveTimeoutInSec Specifies the timeout in seconds that WebDAV the WebClient service uses after issuing a request, such as “GET /file.ext” or “PUT /file.ext”.	DWORD	Time in seconds	60 decimal
ServerNotFoundCacheLifeTimeInSec Specifies the period of time that a server is cached as non-WebDAV by the WebClient service. Note: The WebClient service maintains a list of non-WebDAV servers that have been contacted. If the server is found in this list, a fail is returned immediately without attempting to contact the server.	DWORD	Time in seconds	60 decimal
SupportLocking Specifies whether the WebClient service supports locking.	DWORD	0 = False 1 = True	1

Note: After changing any of these settings you will need to restart the WebClient service.

Source: Robert McMurray's Blog

Great Microsoft EFS articles and tools

Microsoft EFS (Encrypted File System) can be used in combination with SMB and WebDAV. With SMB on network shares it makes not much sense (see my other notes) because of the strange implementation of using server side profiles and keys. But on local disks or with WebDAV on network filestores it's a great security enhancement out-of-the-box.

But there are a lot of issues and caveats you have to know when you want to deploy EFS in an enterprise infrastructure. Today I found the "ParanoidMike" blog which is a great resource for some of EFS related question:

EFS Certificate Updater
EFS and SYSKEY backgrounder
Why EFS makes no sense on servers

Source: ParanoidMike

Mounting WebDAV Servers (RFC 4709)

Found this RFC today. Well, it's an October 2006 document, I am sorry if this is old news for you :-).

RFC 4709

It's Julian Rescke (greenbytes) again and he does a good job in not only describing an WebDAV announcement technology already used by SAP and others but also included some Windows client script to make the transparent mounting work in any native Windows environment.

Worth looking into because if you plan an infrastructure where WebDAV is used instead of file servers it is a real need to think about a link notation which does not result in the well known "browser view" of WebDAV shares but instead opens an explorer view of the data. Julian's document describes such a way.

On the other hand at least in Windows Vista it is possible to use a file share URL to connect to WebDAV:

\\server.domain@SSL\DavWWWRoot

I will try to collect some more pros and cons about the different ways to mount a WebDAV share - happy about your comments.

Windows Server 2008, the storage story

On the Windows Server Division Weblog, Claude Lorenson is writing about "the future of SMB". He delivers some very interesting details about Windows Server 2008 (Longhorn) and the new features of SMB 2.0. It's obvious that Microsoft invests in SMB, especially to make it usable for the loosely coupled branch offfice scenarios:

SMB 2.0 greatly improves the scalability of SMB 1.0; there is now more open files on a server supported as well as a higher number of shares supported. The protocols have been enhanced to reduce the “chattiness” that makes file sharing on a WAN sometimes painful. With SMB 2.0, customer data has shown the ability to download a 300MB file 35 times faster than with SMB 1.0 using a 100 Mbps link (from 24 minutes to 41 seconds). SMB2.0 will also support transactions, symbolic links and client side encryption. All these features are fully functional when Vista clients are used in combination with Windows Server 2008.

But there is also an important side note which may change a lot when planning next generation storage infrastructures:

The following sentence: "SMB2.0 will also support transactions, symbolic links and client side encryption" is not correct. Transaction support and client side encryption will not be available in Windows Server 2008 and therefore are not in the beta 3 release either.]

Wow... still no SMB encryption. I remember Microsoft is promising this feature since the late 90's. It looks like WebDAV will continue to be the only native file access protocol in Windows Clients which support communication encryption.

See the full story here:
Windows Server 2008, the storage story

WebDAV, Branch Offices and Sharepoint 2007

Given the numerous options a customer has to plan an enterprise wide storage architecture it is not easy to decide about. But during the last 24 months a lot of customers have thought about their enterprise architecture in general and their branch office infrastructure in detail.

Some have chosen to continue to use SMB/CIFS with the help of DFS and delta-replication in R2 and may have even invested in helper technologies from several 3rd parties which offer “branch office boxes” to help cache SMB traffic. These customers will benefit a lot from the upcoming Vista client replication and offline capabilities offered with the Vista release of CSC.

But on the other hand especially the large enterprises do not want to continue the heavy investments of redundant server islands in sometimes hundreds of branch offices and these customers search for combined enterprise storage and document platform solutions which could be offered from products like SharePoint 2007. A lot of good arguments could make this plan working:

• There’s a trend to NOC service centric infrastructures driven by the concepts of the Jericho group and evangelists like Microsoft’s Steve Riley called the “death of the perimeter”. Consolidating the enterprise infrastructure services (storage, collaboration, etc) in secured network operation centers and offering these services to desktop and mobile clients worldwide.

• There’s a general understanding to use more intelligent file servers with collaboration and workflow capabilities

• There are a lot of Microsoft Evangelists praying to use SharePoint instead of file servers
  

• Only WebDAV offers encrypted network transport when not using IPSec

That said it is an attractive strategy to plan upcoming infrastructures around SharePoint 2007. There is a lot of uniqueness against competition in such an infrastructure and it would be a win-win for Microsoft and its customers: The customer can benefit from a streamlined, very productive and scalable architecture and Microsoft establishes the fundament for a long term Vista/Office/Server environment.

But instead of investing in a good implementation of WebDAV as an alternative approach for enterprise storage the reality in XP and Vista shows an unfinished WebDAV client:

• WebDAV/EFS support in Vista results in instant deterministic crashes which leads to the assumption that it was not even worth testing to Microsoft QA

• WebDAV/Windows Explorer often freezes the Explorer when used in copy operations and makes it instable or even unusable

• WebDAV/CSC (Offline Folders) is not implemented at all. That means the very important technology to work with server documents while on the road is not possible with SharePoint. (The alternative approach to sync with Outlook 2007 has several caveats worth to write a separate document – most obvious the missing possibility to create documents while offline; Similar caveats exist when used with Groove).

Conclusion: Microsoft would offer an attractive technology with SharePoint/Office System 2007 in combination with Microsoft Vista if the underlying technology in Vista would support the obvious need to work with documents the way users are expecting: secure, stable and ready for mobile usage.

Why another Blog about WebDAV?

The WebDAV specification was developed in the mid 90's and several RFCs describe the details about the protocol itself and other needed details like the attributes or security specs. But being available for nearly 10 years now it seems that there is still no perfect solution for a day-to-day usage of WebDAV as the primary protocol to access documents and other files in a corporate environment. Beside its obvious advantages like founding on the well known HTTP protocol and the well know SSL/TLS security channel it seems that the reality is affected by the poor Microsoft implementation in Windows XP and Vista, the poor implementation in several commercial server products and the absence of an offline solution.

The intention of this blog is to collect all available resources to make WebDAV a usable choice for corporations and private users.