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25-405: Lanman may refer to: LAN Manager , an obsolete authentication protocol for Microsoft Windows LAN Manager hash , the hashing algorithm used by LAN Manager Lanman (surname) Lanman-Wright Hall at Yale, named after William K. Lanman Topics referred to by the same term [REDACTED] This disambiguation page lists articles associated with

50-462: A trusted third party , and optionally may use public-key cryptography during certain phases of authentication. Kerberos uses UDP port 88 by default. The protocol was named after the character Kerberos (or Cerberus ) from Greek mythology , the ferocious three-headed guard dog of Hades . The Massachusetts Institute of Technology (MIT) developed Kerberos in 1988 to protect network services provided by Project Athena . Its first version

75-445: A LM hash from being generated for their own password by using a password at least fifteen characters in length. —NTLM hashes have in turn become vulnerable in recent years to various attacks that effectively make them as weak today as LanMan hashes were back in 1998. Many legacy third party SMB implementations have taken considerable time to add support for the stronger protocols that Microsoft has created to replace LM hashing because

100-408: A domain (or not part of the same trusted domain environment), Windows will instead use NTLM for authentication between client and server. Internet web applications can enforce Kerberos as an authentication method for domain-joined clients by using APIs provided under SSPI . Microsoft Windows and Windows Server include setspn , a command-line utility that can be used to read, modify, or delete

125-402: A version called "eBones", which could be freely used in any country. Sweden's Royal Institute of Technology released another reimplementation called KTH-KRB. Neuman and John Kohl published version 5 in 1993 with the intention of overcoming existing limitations and security problems. Version 5 appeared as RFC 1510 , which was then made obsolete by RFC 4120 in 2005. In 2005,

150-481: Is considered obsolete and current Windows operating systems use the stronger NTLMv2 or Kerberos authentication methods, Windows systems before Windows Vista / Windows Server 2008 enabled the LAN Manager hash by default for backward compatibility with legacy LAN Manager and Windows ME or earlier clients, or legacy NetBIOS -enabled applications. It has for many years been considered good security practice to disable

175-603: The Internet Engineering Task Force (IETF) Kerberos working group updated specifications. Updates included: MIT makes an implementation of Kerberos freely available, under copyright permissions similar to those used for BSD . In 2007, MIT formed the Kerberos Consortium to foster continued development. Founding sponsors include vendors such as Oracle , Apple Inc. , Google , Microsoft , Centrify Corporation and TeamF1 Inc., and academic institutions such as

200-655: The RC4 cipher. While Microsoft uses and extends the Kerberos protocol, it does not use the MIT software. Kerberos is used as the preferred authentication method: in general, joining a client to a Windows domain means enabling Kerberos as the default protocol for authentications from that client to services in the Windows domain and all domains with trust relationships to that domain. In contrast, when either client or server or both are not joined to

225-595: The Royal Institute of Technology in Sweden, Stanford University, MIT, and vendors such as CyberSafe offering commercially supported versions. The client authenticates itself to the Authentication Server (AS) which is part of the key distribution center (KDC) . The KDC issues a ticket-granting ticket (TGT) , which is time stamped and encrypts it using the ticket-granting service's (TGS) secret key and returns

250-521: The open source communities supporting these libraries first had to reverse engineer the newer protocols— Samba took 5 years to add NTLMv2 support, while JCIFS took 10 years. Poor patching regimes subsequent to software releases supporting the feature becoming available have contributed to some organisations continuing to use LM Hashing in their environments, even though the protocol is easily disabled in Active Directory itself. Lastly, prior to

275-606: The KDC and usually shares the same host as the authentication server. The service must have already been registered with the TGS with a Service Principal Name (SPN) . The client uses the SPN to request access to this service. After verifying that the TGT is valid and that the user is permitted to access the requested service, the TGS issues a service ticket (ST) and session keys to the client. The client then sends

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300-704: The LM hash by default. Kerberos is used in Active Directory Environments. The major weaknesses of LAN Manager authentication protocol are: To address the security weaknesses inherent in LM encryption and authentication schemes, Microsoft introduced the NTLMv1 protocol in 1993 with Windows NT 3.1 . For hashing, NTLM uses Unicode support, replacing LMhash=DESeach(DOSCHARSET(UPPERCASE(password)), "KGS!@#$ %") by NThash= MD4 ( UTF-16 -LE(password)) , which does not require any padding or truncating that would simplify

325-497: The LM hash has several weaknesses in its design. This makes such hashes crackable in a matter of seconds using rainbow tables , or in a few minutes using brute force . Starting with Windows NT , it was replaced by NTLM , which is still vulnerable to rainbow tables, and brute force attacks unless long, unpredictable passwords are used, see password cracking . NTLM is used for logon with local accounts except on domain controllers since Windows Vista and later versions no longer maintain

350-509: The Service Principal Names (SPN) for an Active Directory service account . Many Unix-like operating systems, including FreeBSD , Apple's macOS , Red Hat Enterprise Linux , Oracle 's Solaris , IBM's AIX , HP-UX and others, include software for Kerberos authentication of users or services. A variety of non-Unix like operating systems such as z/OS , IBM i and OpenVMS also feature Kerberos support. Embedded implementation of

375-448: The basis of tickets to allow nodes communicating over a non-secure network to prove their identity to one another in a secure manner. Its designers aimed it primarily at a client–server model, and it provides mutual authentication —both the user and the server verify each other's identity. Kerberos protocol messages are protected against eavesdropping and replay attacks . Kerberos builds on symmetric-key cryptography and requires

400-512: The compromised LM and NTLMv1 authentication protocols where they aren't needed. Starting with Windows Vista and Windows Server 2008, Microsoft disabled the LM hash by default; the feature can be enabled for local accounts via a security policy setting, and for Active Directory accounts by applying the same setting via domain Group Policy . The same method can be used to turn the feature off in Windows 2000, Windows XP and NT. Users can also prevent

425-403: The encrypted result to the user's workstation. This is done infrequently, typically at user logon; the TGT expires at some point although it may be transparently renewed by the user's session manager while they are logged in. When the client needs to communicate with a service on another node (a "principal", in Kerberos parlance), the client sends the TGT to the TGS, which is another component of

450-605: The key. On the negative side, the same DES algorithm was used with only 56-bit encryption for the subsequent authentication steps, and there is still no salting. Furthermore, Windows machines were for many years configured by default to send and accept responses derived from both the LM hash and the NTLM hash, so the use of the NTLM hash provided no additional security while the weaker hash was still present. It also took time for artificial restrictions on password length in management tools such as User Manager to be lifted. While LAN Manager

475-428: The release of Windows NT Advanced Server in 1993. Many vendors shipped licensed versions, including: The LM hash is computed as follows: LAN Manager authentication uses a particularly weak method of hashing a user's password known as the LM hash algorithm, stemming from the mid-1980s when viruses transmitted by floppy disks were the major concern. Although it is based on DES , a well-studied block cipher ,

500-415: The release of Windows Vista, many unattended build processes still used a DOS boot disk (instead of Windows PE ) to start the installation of Windows using WINNT.EXE, something that requires LM hashing to be enabled for the legacy LAN Manager networking stack to work. Kerberos (protocol) Kerberos ( / ˈ k ɜːr b ər ɒ s / ) is a computer-network authentication protocol that works on

525-457: The ticket to the service server (SS) along with its service request. The protocol is described in detail below. Windows 2000 and later versions use Kerberos as their default authentication method. Some Microsoft additions to the Kerberos suite of protocols are documented in RFC 3244 "Microsoft Windows 2000 Kerberos Change Password and Set Password Protocols". RFC 4757 documents Microsoft's use of

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550-481: The title Lanman . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Lanman&oldid=701681129 " Category : Disambiguation pages Hidden categories: Short description is different from Wikidata All article disambiguation pages All disambiguation pages LAN Manager The LAN Manager OS/2 operating system

575-461: Was also available. LAN Manager/X was the basis for Digital Equipment Corporation 's Pathworks product for OpenVMS , Ultrix and Tru64 . In 1990, Microsoft announced LAN Manager 2.0 with a host of improvements, including support for TCP/IP as a transport protocol for SMB, using NetBIOS over TCP/IP (NBT). The last version of LAN Manager, 2.2, which included an MS-OS/2 1.31 base operating system, remained Microsoft's strategic server system until

600-642: Was co-developed by IBM and Microsoft , using the Server Message Block (SMB) protocol. It originally used SMB atop either the NetBIOS Frames (NBF) protocol or a specialized version of the Xerox Network Systems (XNS) protocol. These legacy protocols had been inherited from previous products such as MS-Net for MS-DOS , Xenix-NET for MS-Xenix , and the afore-mentioned 3+Share. A version of LAN Manager for Unix-based systems called LAN Manager/X

625-808: Was primarily designed by Steve Miller and Clifford Neuman based on the earlier Needham–Schroeder symmetric-key protocol . Kerberos versions 1 through 3 were experimental and not released outside of MIT. Kerberos version 4, the first public version, was released on January 24, 1989. Since Kerberos 4 was developed in the United States, and since it used the Data Encryption Standard (DES) encryption algorithm, U.S. export control restrictions prevented it from being exported to other countries. MIT created an exportable version of Kerberos 4 with all encryption code removed, called "Bones". Eric Young of Australia's Bond University reimplemented DES into Bones, in

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