Editing Apple Filing Protocol

{{short description|Computer network protocol}}
{{distinguish|text=[[Apple File System]] (APFS), a file system for macOS, iOS, tvOS and watchOS, currently being developed and deployed by Apple Inc}}
{{Infobox networking protocol|title=Apple Filing Protocol|developer=Apple, Inc.|purpose=File services|is stack=no|ports=548}}
The '''Apple Filing Protocol''' ('''AFP'''), formerly '''AppleTalk Filing Protocol''', is a [[proprietary protocol|proprietary]] [[Communications protocol|network protocol]], and part of the '''Apple File Service''' ('''AFS'''), that offers file services for [[macOS]], [[classic Mac OS]], and [[Apple II]] computers.  In [[OS X Mountain Lion|OS X 10.8 Mountain Lion]] and earlier, AFP was the primary protocol for file services. Starting with [[OS X Mavericks|OS X 10.9 Mavericks]], [[Server Message Block]] (SMB) was made the primary file sharing protocol, with the ability to run an AFP server removed later in [[macOS Big Sur|macOS 11 Big Sur]]<ref>{{Cite web|last=Fleishman|first=Glenn|date=2020-12-18|title=AFP is no longer supported in macOS Big Sur. Here's the fix|url=https://www.macworld.com/article/3600899/using-afp-to-share-a-mac-drive-its-time-to-change.html|access-date=2021-01-09|website=Macworld|language=en}}</ref> and the client being marked for deprecation in the 15.5 update of [[macOS Sequoia|MacOS Sequoia]].<ref>{{Cite web |title=What's new for enterprise in macOS Sequoia |url=https://support.apple.com/en-us/121011 |access-date=2025-05-16 |website=Apple Support |language=en}}</ref> AFP supports [[Unicode]] file names, [[POSIX]] and [[access-control list]] permissions, [[resource fork]]s, named extended attributes, and advanced [[file locking]].

==Compatibility==
AFP versions 3.0 and greater rely exclusively on [[Internet protocol suite|TCP/IP]] (port 548) for establishing communication, supporting [[AppleTalk]] only as a [[service discovery]] protocol. The AFP 2.x family supports both TCP/IP (using [[Data Stream Interface]]) and AppleTalk for communication and service discovery. Many third-party AFP implementations use AFP 2.x, thereby supporting AppleTalk as a connection method. Still earlier versions rely exclusively on AppleTalk. For this reason, some older literature refers to AFP as "AppleTalk Filing Protocol".  Other literature may refer to AFP as "AppleShare", the name of the [[Mac OS 9]] (and earlier) AFP client.

Notable current compatibility topics are:
# [[Mac OS X v10.4]] and later eliminates support for AFP servers that rely solely on AppleTalk for communication.
# Computers using classic Mac OS can connect to AFP 3.x servers, with some limitations. For example, the maximum file size in Mac OS 8 is 2 [[gigabyte]]s. Typically, Mac OS 9.1 or later is recommended for connecting to AFP 3.x servers; for versions of original Mac OS prior to 9.1, installation of the [[AppleShare]] client 3.8.8 is required.
# AFP 3.0 and later is required for network home directories, since Mac OS X requires [[POSIX]] permissions on user home directories. Single sign-on using [[Kerberos (protocol)|Kerberos]] requires AFP 3.1.
#APFS: AFP is incompatible with sharing of [[Apple_File_System|APFS]] volumes but is still usable as a Time Machine destination in High Sierra.

==History==
Early implementations of AFP server software were available in Mac OS starting with System 6, in AppleShare and AppleShare IP, and in early "1.x" releases of Mac OS X Server. In client operating systems, AFP was called "Personal File Sharing", and supported up to ten simultaneous connections.<ref name="classiclimits">{{cite web|url=http://support.apple.com/kb/TA21611|title=AppleShare & AppleShare IP File Sharing: Chart of All Limitations|access-date=2012-06-10}}</ref> These AFP implementations relied on version 1.x or 2.x of the protocol. AppleShare IP 5.x, 6.x, and the "1.x" releases of Mac OS X Server introduced AFP version 2.2. This was the first version to offer transport connections using TCP/IP as well as AppleTalk. It also increased the maximum share point size from four [[gigabyte]]s to two [[terabyte]]s,<ref name="classiclimits"/> although the maximum file size that could be stored remained at two gigabytes due to limitations in the original Mac OS.<ref>{{cite web|url=http://support.apple.com/kb/TA21924|title=Mac OS 8, 9: Mac OS Extended Format - Volume and File Limits|access-date=2012-06-10}}</ref>

Changes made in AFP since version 3.0 represent major advances in the protocol, introducing features designed specifically for Mac OS X clients. 

However, like the AppleShare client in original Mac OS, the AFP client in Mac OS X continues to support [[type code|type]] and [[creator code]]s, along with [[filename extension]]s.

AFP 3.0 was introduced in [[Mac OS X Server]] 10.0.3, and was used through Mac OS X Server 10.1.5. It was the first version to use the UNIX-style POSIX permissions model and Unicode [[UTF-8]] file name encodings. Version 3.0 supported a maximum share point and file size of two terabytes, the maximum file size and volume size for Mac OS X until version 10.2.<ref name="hfspluslimits">{{cite web|url=http://support.apple.com/kb/HT2422|title=Mac OS X: Mac OS Extended Format - Volume and File Limits|access-date=2012-06-10}}</ref> (Note that the maximum file size changed from version 2.2, described above.) Before AFP 3.0, 31 bytes was the maximum length of a filename sent over AFP.

AFP 3.1 was introduced in Mac OS X Server version 10.2. Notable changes included support for Kerberos authentication, automatic client reconnect, NFS resharing, and secure AFP connections via [[Secure Shell]] (SSH). The maximum share point and file size increased to 8 [[terabytes]] with Mac OS X Server 10.2,<ref name="hfspluslimits"/><ref>{{cite web|url=http://support.apple.com/kb/TA21110|title=Mac OS X Server 10.2: Tested and theoretical maximums (limits)|access-date=2012-06-10}}</ref> and then to 16 terabytes with Mac OS X Server 10.3.<ref name="hfspluslimits"/><ref>{{cite web|url=http://support.apple.com/kb/TA21342|title=Mac OS X Server 10.3: Tested and theoretical maximums (limits)|access-date=2012-06-10}}</ref>

AFP 3.2 adds support for Access Control Lists and [[extended attributes]] in Mac OS X Server 10.4. Maximum share point size is at least 16 terabytes, although Apple has not published a limits document for Mac OS X Server 10.4. Apple implemented AFP 3.2 support in their [[AirPort Time Capsule]] wireless router device.

AFP 3.2+ was introduced in [[Mac OS X Leopard]] and adds case sensitivity support and improves support for [[Time Machine (macOS)|Time Machine]] (synchronization, lock stealing, and sleep notifications).

AFP 3.3 mandates support for Replay Cache functionality (required for [[Time Machine (macOS)|Time Machine]]).

AFP 3.4, introduced in [[OS X Mountain Lion]], includes a minor change in the mapping of POSIX errors to AFP errors.

See Apple's Developer documentation on AFP Version Differences.<ref>{{cite web|url=https://developer.apple.com/library/mac/#documentation/Networking/Conceptual/AFP/AFPVersionDifferences/AFPVersionDifferences.html|title=Apple's Developer documentation on AFP Version Differences|access-date=2011-09-15}}</ref>

==The macOS client==
In Mac OS X Tiger, users can connect to AFP servers by browsing for them in the [[Computer network|Network]] globe or entering an AFP [[Uniform Resource Locator]] (URL) into the Connect to Server dialog. In Mac OS X Leopard and later releases, AFP shares are displayed in the Finder sidebar. AFP URLs take the form: ''afp://{{angbr|server}}/{{angbr|share}}'', where {{angbr|server}} is the server's [[IP address]], [[Domain Name System]] (DNS) name, or [[Bonjour (software)|Bonjour]] name, and {{angbr|share}} is the name of the share point.  In Snow Leopard and later, a URL of the form ''afp://{{angbr|server}}/{{angbr|share}}/{{angbr|path}}'' can be used to mount a subdirectory underneath a share point.

macOS also offers Personal File Sharing, a "light" implementation of the current version of AFP. In Mac OS X 10.4, users can share the contents of their Public folders by checking Personal File Sharing in the Sharing section of System Preferences.

AFP URLs for AppleTalk servers took the form: ''afp://at/{{angbr|AppleTalk name}}:{{angbr|AppleTalk zone}}''. For networks without AppleTalk zones, an [[asterisk]] (*) would be substituted for the zone name.

==Third-party implementations==
Third party server implementations of AFP are available from a number of companies.
*An [[Open-source software|open source]] AFP server called [[Netatalk]] (AFP 3.4) is available for [[Unix-like]] operating systems. A range of [[Network Attached Storage|NAS]] solutions integrate Netatalk to enable support for AFP.
*[[Novell Open Enterprise Server]] supports AFP.
*[[Microsoft]] includes AFP 2.2 server support as an option in some versions of [[Windows]] ([[Windows NT 4.0|NT]], [[Windows 2000|2000]] & [[Windows Server 2003|2003]]). Windows NT Server (3 and 4) only supported AppleTalk, [[Windows 2000|2000]] added AppleShare over IP; Services for Macintosh (SFM), was removed from [[Windows Server 2008]] onwards.
*[[Novell]]'s [[NetWare]] supports AFP.
*[http://www.helios.de HELIOS UB+] supports AFP on a whole array of different Unix based platforms.
*The [[Open-source software|open source]] [[Filesystem in Userspace]] ([http://fuse.sourceforge.net FUSE]) and command-line client implementation [http://sourceforge.net/projects/afpfs-ng afpfs-ng] for [[Linux]] and [[Unix-like]] operating systems
*[[GroupLogic]] ExtremeZ-IP (AFP 3.3) and [http://www.cyansoftware.com/MacServerIP.htm MacServerIP] for Windows offer AFP 3.x support - now [[Acronis]] [http://www.acronis.com/en-us/mobility/mac-windows-compatibility/ Files Connect].
*[http://www.snapserver.com/ Adaptec's Snap Server] is a NAS with a proprietary implementation of AFP 3.1.
*[http://sourceforge.net/projects/jaffer/ Jaffer] is a Java implementation of AFP 3.1.
*[http://www.xinet.com/ Xinet] from North Plains Systems offers an AFP platform that can run on most Unix based platforms.  One of their products, ka-share, has been a main stay on [[Solaris (operating system)|Solaris]] [[SPARC]] and [[Silicon Graphics]] [[IRIX]] platforms.
*Columbia AppleTalk Package (CAP) is a historical open source implementation of AFP and AppleTalk from [[Columbia University]] that was last updated in 1996.<ref>{{cite web | url=https://github.com/mabam/CAP/blob/master/README | title=Mabam/CAP | website=[[GitHub]] }}</ref>
*supported by [[GVfs]] through gfvs-afp-volume-monitor<ref>{{cite web |url=https://wiki.gnome.org/Projects/gvfs/backends |title=Back-ends for GVfs}}</ref>

==See also==
*[[List of network protocols]]
*[[List of file systems]]

==References==
{{reflist}}

==External links==
*[https://web.archive.org/web/20051102080247/http://manuals.info.apple.com/en/File_Services_v10.4.pdf File Services Manual for Mac OS X Server 10.4]
*[https://developer.apple.com/library/content/documentation/Networking/Conceptual/AFP/Introduction/Introduction.html#//apple_ref/doc/uid/TP40000854-CH1-SW1 Apple Filing Protocol Programming Guide]
*[https://web.archive.org/web/20091113195834/https://developer.apple.com/mac/library/documentation/Networking/Reference/AFP_Reference/Reference/reference.html Apple Filing Protocol Reference]
*[https://support.apple.com/kb/TA21112?viewlocale=en_US&locale=en_US Mac OS X: Some Mac OS X Applications and Services Require AFP 3.0 or Later ]
*[https://web.archive.org/web/20071128090357/http://developer.apple.com/MacOs/opentransport/docs/dev/Inside_AppleTalk.pdf Inside AppleTalk - original specification for the AppleTalk protocol stack including AFP]
*[http://www.accsystems.com/glossary.htm Glossary of Networking Terms]
*[https://web.archive.org/web/20040402142541/http://www.newsfactor.com/story.xhtml?story_title=How_Secure_Is_OS_X_&story_id=23467 NewsFactor Network article, A]
*[https://web.archive.org/web/20080508023713/http://docs.info.apple.com/article.html?artnum=8647 Macintosh: File System Specifications and Terms]
*[https://developer.apple.com/legacy/library/technotes/tn/tn1150.html Apple Technical Note TN1150 on the HFS Plus Volume Format]
*[http://appleinsider.com/articles/13/06/11/apple-shifts-from-afp-file-sharing-to-smb2-in-os-x-109-mavericks Apple shifts from AFP to SMB2]

{{File systems}}

[[Category:Apple Inc. file systems]]
[[Category:Network protocols]]
[[Category:Network file systems]]
[[Category:Presentation layer protocols]]