Longhorn Server - the little things mean a lot - SMB2 Protocol

  • Comments 19
  • Likes

As we get closer to Beta 2 of Windows Server codenamed "Longhorn" - there will be a lot of talk on the bigger features that Longhorn will deliver....Network Access Protection, Read-Only Domain Controller, Server Core, Secure Startup, Role Management Tools, the list goes on.

These are all no doubt nifty and cool features, but the lesser-known features of Longhorn Server are sometimes the ones that can really make a difference to a customer. 

One of the features that have come a long way with Longhorn server is the SMB protocol - now SMB2. The original SMB protocol is filled with many limitations that were acceptable when it was designed, but seems completely inadequate now that technology has grown significantly.

We have listened to our customers on the limitations that were present with the original SMB protocol and have removed the restrictive constants in the protocol so we never need to worry about the protocol itself being the limiting factor for scalability. This includes increasing the number of concurrent open file handles on the server, the number of shares that a server can share out amongst other key enhacements which inlcude:

  • SMB2 will have transaction support, i.e. full two-phase commit transactional semantics are available over the new SMB protocol. This takes advantage of the new Transactional File System (TxF) feature in NTFS in Longhorn Server
  • Client Side Encryption. This allows over the wire encryption of data, i.e. a file is encrypted on the client and sent out to the server where previously the file would have been sent in the clear over the wire and encrypted on the server
  • Support for symbolic links over the new protocol
  • Supports an arbitrary extensible way of compounding operations to reduce round trips. This is what will primarily enable less chattiness which has often been a major pain point
  • The new protocol supports larger buffer sizes than previously allowed

Cool, huh?

- Ward Ralston

Your comment has been posted.   Close
Thank you, your comment requires moderation so it may take a while to appear.   Close
Leave a Comment
  • This is excellent news. Look forward to it. Do you have any other information or docs on the changes made to SMB in SMB2? I'd be curious readnig more on it. Thanks.


  • Damn straight that's cool... I am struggling to see many reasons to upgrade clients to Vista (in an enterprise environment), but I'll be making sure we start dropping Longhorn Server as soon as it's RTM :-)

    Even the Unix guys gave props when I told them you can now build a Windows server without a GUI - man that is a long overdue improvement!

  • These new features sound great!

    Would it be possible for you to expand on what you mean by "symbolic links over the new protocol?" Will junction points be able to target network shares?

    Also, is there any chance of getting "Client Side Compression," so that a file that has NTFS compression turned on will be sent over the wire compressed and decompressed by the client, rather than decompressed by the server and then sent over the wire (and vice versa)?

  • Sounds Cool!

    Will SMB2 be a public free or licensable protocol?

  • While I, as I'm sure you and everyone else sane, consider the original SMB protocol with its dozen+ variations to be quite a mess, I'd still like to see in writing:
    1. Yes, we this time fully specified SMB2, and we did it good.
    2. Yes, the specification will obviously be available to everyone and all from an RFC. (after all, wasn't that what MS tried to fool us all into with CIFS?)

  • Also will it be backwards compatible to support old clients ?

  • Will you make enough information public for the samba team to be able to support SMB2?

  • does any one know how to access a file share from windows vista / long horn server by ipv6 address...more over whether is there any support for ipv6 that  microsoft has provided??

  • PingBack from

  • PingBack from

  • 環境: Windows Vista Visual Studio 2005 (In this post, English follows) ============================ こんにちは。

  • bathroom vanities

  • bathroom vanities

  • bathroom faucets

  • bathroom sinks