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68-595: File servers are commonly found in schools and offices, where users use a local area network to connect their client computers. A file server may be dedicated or non-dedicated. A dedicated server is designed specifically for use as a file server, with workstations attached for reading and writing files and databases . File servers may also be categorized by the method of access: Internet file servers are frequently accessed by File Transfer Protocol or by HTTP (but are different from web servers , that often provide dynamic web content in addition to static files). Servers on

136-478: A SAN . Network-attached storage (NAS) is file-level computer data storage connected to a computer network providing data access to a heterogeneous group of clients. NAS devices specifically are distinguished from file servers generally in a NAS being a computer appliance – a specialized computer built from the ground up for serving files – rather than a general purpose computer being used for serving files (possibly with other functions). In discussions of NASs,

204-580: A free-software re-implementation (using reverse engineering ) of the SMB/CIFS networking protocol for Unix-like systems, initially to implement an SMB server to allow PC clients running the DEC Pathworks client to access files on SunOS machines. Because of the importance of the SMB protocol in interacting with the widespread Microsoft Windows platform, Samba became a popular free software implementation of

272-445: A hotspot service. Network topology describes the layout of interconnections between devices and network segments. At the data link layer and physical layer , a wide variety of LAN topologies have been used, including ring , bus , mesh and star . Simple LANs generally consist of cabling and one or more switches . A switch can be connected to a router , cable modem , or ADSL modem for Internet access. A LAN can include

340-548: A wide area network (WAN). CIFS Server Message Block ( SMB ) is a communication protocol used to share files, printers , serial ports , and miscellaneous communications between nodes on a network . On Microsoft Windows , the SMB implementation consists of two vaguely named Windows services : "Server" (ID: LanmanServer ) and "Workstation" (ID: LanmanWorkstation ). It uses NTLM or Kerberos protocols for user authentication. It also provides an authenticated inter-process communication (IPC) mechanism. SMB

408-547: A Defense Department teleconferencing application. This demonstrated the feasibility of employing TCP/IP LANs to interconnect Worldwide Military Command and Control System (WWMCCS) computers at command centers throughout the United States. However, WWMCCS was superseded by the Global Command and Control System (GCCS) before that could happen. During the same period, Unix workstations were using TCP/IP networking. Although

476-420: A LAN are usually accessed by SMB / CIFS protocol ( Windows and Unix-like ) or NFS protocol (Unix-like systems). Database servers , that provide access to a shared database via a database device driver, are not regarded as file servers even when the database is stored in files, as they are not designed to provide those files to users and tend to have differing technical requirements. In modern businesses,

544-668: A compatible SMB client and server to allow non-Windows operating systems, such as Unix-like operating systems, to interoperate with Windows. As of version 3 (2003), Samba provides file and print services for Microsoft Windows clients and can integrate with a Windows NT 4.0 server domain, either as a Primary Domain Controller (PDC) or as a domain member. Samba4 installations can act as an Active Directory domain controller or member server, at Windows 2008 domain and forest functional levels. Package managers in Linux distributions can search for

612-622: A lack of support for newer authentication protocols like NTLMv2 and Kerberos in favor of protocols like NTLMv1, LanMan , or plaintext passwords. Real-time attack tracking shows that SMB is one of the primary attack vectors for intrusion attempts, for example the 2014 Sony Pictures attack , and the WannaCry ransomware attack of 2017. In 2020, two SMB high-severity vulnerabilities were disclosed and dubbed as SMBGhost ( CVE-2020-0796 ) and SMBleed ( CVE-2020-1206 ), which when chained together can provide RCE (Remote Code Execution) privilege to

680-631: A large variety of SMB clients and servers. SMB1 features many versions of information for commands (selecting what structure to return for a particular request) because features such as Unicode support were retro-fitted at a later date. SMB2 involves significantly reduced compatibility-testing for implementers of the protocol. SMB2 code has considerably less complexity since far less variability exists (for example, non-Unicode code paths become redundant as SMB2 requires Unicode support). Apple migrated to SMB2 (from their own Apple Filing Protocol , now legacy) starting with OS X 10.9 "Mavericks" . This transition

748-445: A multiprotocol, identity-aware platform for network access to files used in OEM storage products built on Linux/Unix based devices. The platform could be used for traditional NAS, Cloud Gateway, and Cloud Caching devices for providing secure access to files across a network. Likewise was purchased by EMC Isilon in 2012. KSMBD is an open source in-kernel CIFS/SMB server implementation for

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816-479: A network with a smaller number of hosts, increased broadcast traffic can cause problems as the number of hosts on the network increases. The implementation of name resolution infrastructure in the form of Windows Internet Naming Service (WINS) or Domain Name System (DNS) resolves this problem. WINS was a proprietary implementation used with Windows NT 4.0 networks, but brought about its own issues and complexities in

884-469: A network. However the SMB itself does not use broadcasts—the broadcast problems commonly associated with SMB actually originate with the NetBIOS service location protocol. By default, a Microsoft Windows NT 4.0 server used NetBIOS to advertise and locate services. NetBIOS functions by broadcasting services available on a particular host at regular intervals. While this usually makes for an acceptable default in

952-443: A new opportunistic locking mechanism. SMB 3.0 (previously named SMB 2.2) was introduced with Windows 8 and Windows Server 2012 . It brought several significant changes that are intended to add functionality and improve SMB2 performance, notably in virtualized data centers : It also introduces several security enhancements, such as end-to-end encryption and a new AES based signing algorithm. SMB 3.0.2 (known as 3.02 at

1020-489: A polling/selecting central unit with a multidrop bus with Master/slave (technology) arbitration. The development and proliferation of personal computers using the CP/M operating system in the late 1970s, and later DOS -based systems starting in 1981, meant that many sites grew to dozens or even hundreds of computers. The initial driving force for networking was to share storage and printers , both of which were expensive at

1088-411: A secondary name resolution protocol for interoperability with legacy Windows environments and applications. Further, Microsoft DNS servers can forward name resolution requests to legacy WINS servers in order to support name resolution integration with legacy (pre-Windows 2000) environments that do not support DNS. Network designers have found that latency has a significant impact on the performance of

1156-519: A simple network operating system LAN Manager and its cousin, IBM's LAN Server . None of these enjoyed any lasting success; Netware dominated the personal computer LAN business from early after its introduction in 1983 until the mid-1990s when Microsoft introduced Windows NT . In 1983, TCP/IP was first shown capable of supporting actual defense department applications on a Defense Communication Agency LAN testbed located at Reston, Virginia. The TCP/IP-based LAN successfully supported Telnet , FTP , and

1224-422: A single request, which significantly reduces the number of round-trips the client needs to make to the server, improving performance as a result. SMB1 also has a compounding mechanism—known as AndX—to compound multiple actions, but Microsoft clients rarely use AndX. It also introduces the notion of "durable file handles": these allow a connection to an SMB server to survive brief network outages, as are typical in

1292-530: A transport (a largely experimental effort that required further refinement). Microsoft submitted some partial specifications as Internet Drafts to the IETF . These submissions have since expired. Microsoft introduced a new version of the protocol (SMB 2.0 or SMB2) in 2006 with Windows Vista and Windows Server 2008 . Although the protocol is proprietary, its specification has been published to allow other systems to interoperate with Microsoft operating systems that use

1360-495: A wide variety of other network devices such as firewalls , load balancers , and network intrusion detection . Advanced LANs are characterized by their use of redundant links with switches using the spanning tree protocol to prevent loops, their ability to manage differing traffic types via quality of service (QoS), and their ability to segregate traffic with VLANs . At the higher network layers, protocols such as NetBIOS , IPX/SPX , AppleTalk and others were once common, but

1428-438: A wireless network, without having to incur the overhead of re-negotiating a new session. SMB2 includes support for symbolic links . Other improvements include caching of file properties, improved message signing with HMAC SHA-256 hashing algorithm and better scalability by increasing the number of users, shares and open files per server among others. The SMB1 protocol uses 16-bit data sizes, which amongst other things, limits

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1496-564: Is a computer network that interconnects computers within a limited area such as a residence, school, laboratory, university campus or office building. By contrast, a wide area network (WAN) not only covers a larger geographic distance, but also generally involves leased telecommunication circuits . Ethernet and Wi-Fi are the two most common technologies in use for local area networks. Historical network technologies include ARCNET , Token Ring and AppleTalk . The increasing demand and usage of computers in universities and research labs in

1564-594: Is a family of portable SMB client and server implementations developed by Visuality Systems , an Israel-based company established in 1998 by Sam Widerman, formerly the CEO of Siemens Data Communications. The NQ family comprises an embedded SMB stack (written in C), a Pure Java SMB Client, and a storage SMB Server implementation. All solutions support the latest SMB 3.1.1 dialect. NQ for Linux , NQ for WinCE , iOS, Android, VxWorks and other real-time operating systems are all supported by

1632-445: Is a proprietary SMB server implementation developed by Tuxera that can be run either in kernel or user space . It supports SMB 3.1.1 and all previous versions, additionally advanced SMB features like continuous availability (persistent handles) scale-out, RDMA (SMB Direct), SMB multichannel, transparent compression, shadow copy . Likewise developed a CIFS/SMB implementation (versions 1.0, 2.0, 2.1 and NFS 3.0) in 2009 that provided

1700-405: Is an extremely chatty protocol, which is not such an issue on a local area network (LAN) with low latency. It becomes very slow on wide area networks (WAN) as the back and forth handshake of the protocol magnifies the inherent high latency of such a network. Later versions of the protocol reduced the high number of handshake exchanges. One approach to mitigating the inefficiencies in the protocol

1768-409: Is notable for its now-common scheme of representing symlinks. This "Minshall-French" format shows symlinks as textual files with a .symlink extension and a Xsym\n magic number, always 1067 bytes long. This format is also used for storing symlinks on native SMB servers or unsupported filesystems. Samba supports this format with an mfsymlink option. Docker on Windows also seems to use it. NQ

1836-540: Is still the basis of most commercial LANs today. While optical fiber cable is common for links between network switches , use of fiber to the desktop is rare. In a wireless LAN , users have unrestricted movement within the coverage area. Wireless networks have become popular in residences and small businesses, because of their ease of installation. Most wireless LANs use Wi-Fi as wireless adapters are typically integrated into smartphones , tablet computers and laptops . Guests are often offered Internet access via

1904-1039: Is to use WAN optimization products such as those provided by Riverbed , Silver Peak , or Cisco . A better approach is to upgrade to a later version of SMB. This includes upgrading both NAS devices as well as Windows Server 2003. The most effective method to identify SMB1 traffic is with a network analyzer tool, such as Wireshark . Microsoft also provides an auditing tool in Windows Server 2016 to track down devices that use SMB1. Microsoft has marked SMB1 as deprecated in June 2013. Windows Server 2016 and Windows 10 version 1709 do not have SMB1 installed by default. In 1996, when Sun Microsystems announced WebNFS , Microsoft launched an initiative to rename SMB to Common Internet File System (CIFS) and added more features, including support for symbolic links , hard links , larger file sizes, and an initial attempt at supporting direct connections over TCP port 445 without requiring NetBIOS as

1972-457: The Acorn Atom and Acorn System 2 / 3 / 4 computers in 1981. In the 1980s, several token ring network implementations for LANs were developed. IBM released their own implementation of token ring in 1985, It ran at 4  Mbit/s . IBM claimed that their token ring systems were superior to Ethernet, especially under load, but these claims were debated. IBM's implementation of token ring

2040-541: The IETF , partly in response to formal IETF standardization of version 4 of the Network File System in December 2000 as IETF RFC 3010; however, those SMB-related Internet-Drafts expired without achieving any IETF standards-track approval or any other IETF endorsement. (See http://ubiqx.org/cifs/Intro.html for historical detail.) SMB2 is also a relatively clean break with the past. Microsoft's SMB1 code has to work with

2108-454: The Internet protocol suite (TCP/IP) has prevailed as the standard of choice. LANs can maintain connections with other LANs via leased lines, leased services, or across the Internet using virtual private network technologies. Depending on how the connections are established and secured, and the distance involved, such linked LANs may also be classified as a metropolitan area network (MAN) or

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2176-515: The Kerberos protocol to authenticate users against Active Directory on Windows domain networks. On simpler, peer-to-peer networks, SMB uses the NTLM protocol. Windows NT 4.0 SP3 and later can digitally sign SMB messages to prevent some man-in-the-middle attacks . SMB signing may be configured individually for incoming SMB connections (by the "LanmanServer" service) and outgoing SMB connections (by

2244-458: The TCP and IP protocols for transport. This combination allows file sharing over complex, interconnected networks , including the public Internet. The SMB server component uses TCP port 445. SMB originally operated on NetBIOS over IEEE 802.2 - NetBIOS Frames or NBF - and over IPX/SPX , and later on NetBIOS over TCP/IP (NetBT), but Microsoft has since deprecated these protocols. On NetBT,

2312-501: The cifs-utils package. The package is from the Samba maintainers. NSMB (Netsmb and SMBFS) is a family of in-kernel SMB client implementations in BSD operating systems. It was first contributed to FreeBSD 4.4 by Boris Popov, and is now found in a wide range of other BSD systems including NetBSD and macOS . The implementations have diverged significantly ever since. The macOS version of NSMB

2380-516: The "LanmanWorkstation" service). The default setting for Windows domain controllers running Windows Server 2003 and later is to not allow unsigned incoming connections. As such, earlier versions of Windows that do not support SMB signing from the get-go (including Windows 9x ) cannot connect to a Windows Server 2003 domain controller. SMB supports opportunistic locking (see below) on files in order to improve performance. Opportunistic locking support has changed with each Windows Server release. In

2448-561: The CIFS moniker but continues developing SMB and publishing subsequent specifications. Samba is a free software reimplementation of the SMB protocol and the Microsoft extensions to it. Server Message Block (SMB) enables file sharing , printer sharing , network browsing, and inter-process communication (through named pipes ) over a computer network . SMB serves as the basis for Microsoft's Distributed File System implementation. SMB relies on

2516-412: The Linux kernel. Compared to user-space implementations, it provides better performance and makes it easier to implement some features such as SMB Direct. It supports SMB 3.1.1 and previous versions. Over the years, there have been many security vulnerabilities in Microsoft's implementation of the protocol or components on which it directly relies. Other vendors' security vulnerabilities lie primarily in

2584-416: The SMB 1.0 protocol, that it performs more poorly than other protocols like FTP . Monitoring reveals a high degree of "chattiness" and a disregard of network latency between hosts. For example, a VPN connection over the Internet will often introduce network latency. Microsoft has explained that performance issues come about primarily because SMB 1.0 is a block-level rather than a streaming protocol, that

2652-423: The SMB are proprietary and were initially closed, thereby forcing other vendors and projects to reverse-engineer the protocol to interoperate with it. The SMB 1.0 protocol was eventually published some time after it was reverse engineered, whereas the SMB 2.0 protocol was made available from Microsoft's Open Specifications Developer Center from the outset. In 1991, Andrew Tridgell started the development of Samba,

2720-422: The SMB protocol, opportunistic locking is a mechanism designed to improve performance by controlling caching of network files by the client. Unlike traditional locks , opportunistic lock (OpLocks) are not strictly file locking or used to provide mutual exclusion. There are four types of opportunistic locks. The use of the SMB protocol has often correlated with a significant increase in broadcast traffic on

2788-460: The advent of Novell NetWare which provided even-handed support for dozens of competing card and cable types, and a much more sophisticated operating system than most of its competitors. Of the competitors to NetWare, only Banyan Vines had comparable technical strengths, but Banyan never gained a secure base. 3Com produced 3+Share and Microsoft produced MS-Net . These then formed the basis for collaboration between Microsoft and 3Com to create

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2856-554: The aim of turning DOS INT 21h local file access into a networked file system. Microsoft made considerable modifications to the most commonly used version and included SMB support in the LAN Manager operating system it had started developing for OS/2 with 3Com around 1990. Microsoft continued to add features to the protocol in Windows for Workgroups ( c.  1992 ) and in later versions of Windows. LAN Manager authentication

2924-651: The benches of the European Parliament Hemicycles in Strasbourg and Luxembourg. Early Ethernet ( 10BASE-5 and 10BASE-2 ) used coaxial cable . Shielded twisted pair was used in IBM's Token Ring LAN implementation. In 1984, StarLAN showed the potential of simple unshielded twisted pair by using category 3 cable —the same cable used for telephone systems. This led to the development of 10BASE-T (and its twisted-pair successors ) and structured cabling which

2992-566: The best fit for cost, performance, and capacity. Since the crucial function of a file server is storage, technology has been developed to operate multiple disk drives together as a team, forming a disk array . A disk array typically has cache (temporary memory storage that is faster than the magnetic disks), as well as advanced functions like RAID and storage virtualization . Typically disk arrays increase level of availability by using redundant components other than RAID, such as power supplies . Disk arrays may be consolidated or virtualized in

3060-456: The combination of hardware and software will respond over various levels of demand. Servers may also employ dynamic load balancing scheme to distribute requests across various pieces of hardware. The primary piece of hardware equipment for servers over the last couple of decades has proven to be the hard disk drive . Although other forms of storage are viable (such as magnetic tape and solid-state drives ) disk drives have continued to offer

3128-448: The configurable NQ solution. MoSMB is a user space SMB implementation for Linux. It supports SMB 2.x and SMB 3.x. Key features include Cloud-scale Active-Active Scale-out Clusters, SMB Direct (RDMA), SMB Multichannel, Transparent Failover and Continuous Availability. MoSMB also supports Amazon S3 object storage as storage backend in addition to POSIX file systems such as ext4 , ZFS , Lustre , Ceph , etc. Fusion File Share by Tuxera

3196-493: The design and maintenance of a Microsoft network. Since the release of Windows 2000, the use of WINS for name resolution has been deprecated by Microsoft, with hierarchical Dynamic DNS now configured as the default name resolution protocol for all Windows operating systems. Resolution of (short) NetBIOS names by DNS requires that a DNS client expand short names, usually by appending a connection-specific DNS suffix to its DNS lookup queries. WINS can still be configured on clients as

3264-492: The design of file servers is complicated by competing demands for storage space, access speed, recoverability , ease of administration, security , and budget. This is further complicated by a constantly changing environment, where new hardware and technology rapidly obsolesces old equipment, and yet must seamlessly come online in a fashion compatible with the older machinery. To manage throughput , peak loads, and response time , vendors may utilize queuing theory to model how

3332-468: The hierarchical computing environment which treat users, computers, applications and files as distinct but related entities on the network and grant access based on user or group credentials. In many cases, the directory service spans many file servers, potentially hundreds for large organizations. In the past, and in smaller organizations, authentication could take place directly at the server itself. Local area network A local area network ( LAN )

3400-491: The late 1960s generated the need to provide high-speed interconnections between computer systems. A 1970 report from the Lawrence Radiation Laboratory detailing the growth of their "Octopus" network gave a good indication of the situation. A number of experimental and early commercial LAN technologies were developed in the 1970s. Ethernet was developed at Xerox PARC between 1973 and 1974. Cambridge Ring

3468-587: The maximum block size to 64K. SMB2 uses 32- or 64-bit wide storage fields, and 128 bits in the case of file-handles , thereby removing previous constraints on block sizes, which improves performance with large file transfers over fast networks. Windows Vista/ Server 2008 and later operating systems use SMB2 when communicating with other machines also capable of using SMB2. SMB1 continues in use for connections with older versions of Windows, as well various vendors' NAS solutions. Samba 3.5 also includes experimental support for SMB2. Samba 3.6 fully supports SMB2, except

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3536-519: The modification of user quotas using the Windows quota management tools. When SMB2 was introduced it brought a number of benefits over SMB1 for third party implementers of SMB protocols. SMB1, originally designed by IBM , was reverse engineered , and later became part of a wide variety of non-Windows operating systems such as Xenix , OS/2 and VMS ( Pathworks ). X/Open standardized it partially; Microsoft had submitted Internet-Drafts describing SMB2 to

3604-399: The new protocol. SMB2 reduces the 'chattiness' of the SMB 1.0 protocol by reducing the number of commands and subcommands from over a hundred to just nineteen. It has mechanisms for pipelining , that is, sending additional requests before the response to a previous request arrives, thereby improving performance over high- latency links. It adds the ability to compound multiple actions into

3672-534: The responsibility of file serving from other servers on the network. They typically provide access to files using network file sharing protocols such as NFS , SMB/CIFS ( Server Message Block/Common Internet File System ), or AFP . File servers generally offer some form of system security to limit access to files to specific users or groups. In large organizations, this is a task usually delegated to directory services , such as openLDAP , Novell's eDirectory or Microsoft's Active Directory . These servers work within

3740-456: The server component uses three TCP or UDP ports: 137 (NETBIOS Name Service), 138 (NETBIOS Datagram Service), and 139 (NETBIOS Session Service). In Microsoft Windows, two vaguely named Windows services implement SMB. The "Server" service (ID: LanmanServer ) is in charge of serving shared resources . The "Workstation" service (ID: LanmanWorkstation ) maintains the computer name and helps access shared resources on other computers. SMB uses

3808-583: The term "file server" generally stands for a contrasting term, referring to general purpose computers only. As of 2010 NAS devices are gaining popularity, offering a convenient method for sharing files between multiple computers. Potential benefits of network-attached storage, compared to non-dedicated file servers, include faster data access, easier administration, and simple configuration. NAS systems are networked appliances containing one or more hard drives, often arranged into logical, redundant storage containers or RAID arrays. Network Attached Storage removes

3876-612: The time) was introduced with Windows 8.1 and Windows Server 2012 R2; in those and later releases, the earlier SMB version 1 can be optionally disabled to increase security. SMB 3.1.1 was introduced with Windows 10 and Windows Server 2016 . This version supports AES-128 GCM encryption in addition to AES-128 CCM encryption added in SMB3, and implements pre-authentication integrity check using SHA-512 hash. SMB 3.1.1 also makes secure negotiation mandatory when connecting to clients using SMB versions that support it. The specifications for

3944-560: The time. There was much enthusiasm for the concept, and for several years, from about 1983 onward, computer industry pundits habitually declared the coming year to be, "The year of the LAN". In practice, the concept was marred by the proliferation of incompatible physical layer and network protocol implementations, and a plethora of methods of sharing resources. Typically, each vendor would have its own type of network card, cabling, protocol, and network operating system . A solution appeared with

4012-521: The workstation market segment is now much reduced, the technologies developed in the area continue to be influential on the Internet and in all forms of networking—and the TCP/IP protocol has replaced IPX , AppleTalk , NBF , and other protocols used by the early PC LANs. Econet was Acorn Computers's low-cost local area network system, intended for use by schools and small businesses. It was first developed for

4080-636: Was a relatively high-speed choice of that era, with speeds such as 100 Mbit/s. By 1994, vendors included Cisco Systems , National Semiconductor , Network Peripherals, SysKonnect (acquired by Marvell Technology Group ), and 3Com . FDDI installations have largely been replaced by Ethernet deployments. In 1979, the Electronic voting systems for the European Parliament was using 10 kilometers of simple unshielded twisted pair category 3 cable —the same cable used for telephone systems—installed inside

4148-469: Was developed at Cambridge University starting in 1974. ARCNET was developed by Datapoint Corporation in 1976 and announced in 1977. It had the first commercial installation in December 1977 at Chase Manhattan Bank in New York. In 1979, the Electronic voting systems for the European Parliament was the first installation of a LAN connecting hundreds (420) of microprocessor-controlled voting terminals to

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4216-452: Was fraught with compatibility problems though. Non-default support for SMB2 appeared in fact in OS X 10.7, when Apple abandoned Samba in favor of its own SMB implementation called SMBX after Samba adopted GPLv3 . The Linux kernel 's CIFS client file system has SMB2 support since version 3.7. SMB 2.1, introduced with Windows 7 and Server 2008 R2, introduced minor performance enhancements with

4284-578: Was implemented based on the original legacy SMB specification's requirement to use IBM "LAN Manager" passwords, but implemented DES in a flawed manner that allowed passwords to be cracked. Later, Kerberos authentication was also added. The Windows domain logon protocols initially used 40-bit encryption outside of the United States , because of export restrictions on stronger 128-bit encryption (subsequently lifted in 1996 when President Bill Clinton signed Executive Order 13026 ). SMB 1.0 (or SMB1)

4352-599: Was introduced in Windows Server 2022 . In 1996, Microsoft published a version of SMB 1.0 with minor modifications under the Common Internet File System ( CIFS / s ɪ f s / ) moniker. CIFS was compatible with even the earliest incarnation of SMB, including LAN Manager 's. It supports symbolic links, hard links, and larger file size, but none of the features of SMB 2.0 and later. Microsoft's proposal, however, remained an Internet Draft and never achieved standard status. Microsoft has since discontinued

4420-464: Was originally designed for small LANs ; it has a block size that is limited to 64K, SMB signing creates an additional overhead and the TCP window size is not optimized for WAN links. Solutions to this problem include the updated SMB 2.0 protocol, Offline Files , TCP window scaling and WAN optimization devices from various network vendors that cache and optimize SMB 1.0 and 2.0. Barry Feigenbaum originally designed SMB at IBM in early 1983 with

4488-531: Was originally designed to run on NetBIOS Frames (NetBIOS over IEEE 802.2 ). Since then, it has been adapted to NetBIOS over IPX/SPX (NBX), and NetBIOS over TCP/IP (NetBT). Also, since Windows 2000 , SMB runs on TCP using TCP port 445, a feature known as "direct host SMB". There is still a thin layer (similar to the Session Message packet of NetBT's Session Service) between SMB and TCP. Windows Server 2003, and legacy NAS devices use SMB1 natively. SMB1

4556-638: Was originally developed in 1983 by Barry A. Feigenbaum at IBM to share access to files and printers across a network of systems running IBM's IBM PC DOS . In 1987, Microsoft and 3Com implemented SMB in LAN Manager for OS/2 , at which time SMB used the NetBIOS service atop the NetBIOS Frames protocol as its underlying transport. Later, Microsoft implemented SMB in Windows NT 3.1 and has been updating it ever since, adapting it to work with newer underlying transports: TCP/IP and NetBT . SMB over QUIC

4624-620: Was the basis of the IEEE 802.5 standard. A 16 Mbit/s version of Token Ring was standardized by the 802.5 working group in 1989. IBM had market dominance over Token Ring, for example, in 1990, IBM equipment was the most widely used for Token Ring networks. Fiber Distributed Data Interface (FDDI), a LAN standard, was considered an attractive campus backbone network technology in the early to mid 1990s since existing Ethernet networks only offered 10 Mbit/s data rates and Token Ring networks only offered 4 Mbit/s or 16 Mbit/s rates. Thus it

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