Apple Filing Protocol

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Apple Filing Protocol
Basic data

Maintainer Development stopped
developer Apple, Inc.
Current  version 3.4
(July 25, 2012)
operating system macOS and others

The Apple Filing Protocol ( AFP ; German about Apple filing protocol ) is a network protocol from Apple that computers with the operating systems Mac OS or macOS allows file access over a network.

AFP specifies different AFP versions, the server and client agree on the maximum possible version for both sides during the connection.

Older versions of AFP can only be operated via Apple's proprietary AppleTalk Protocol Stack with DDP as the transmission protocol , but from version 2.2 AFP also runs on pure TCP / IP networks on port 548.

Newer versions of the protocol also support file sizes over 2  GB , long file names (over 31 bytes) and UTF-8 characters in file names.

AFP is a network protocol that uses the features of HFS Plus (the standard Mac OS file system) such as. B. Resource Forks , Type and Creator Codes and the Desktop Database are supported. These were necessary properties under the classic Mac OS, but they are no longer a prerequisite for the operation of Mac OS X.

With OS X Mavericks (10.9, 2012) Apple replaced AFP with SMB2 (Samba), which is why AFP is no longer being developed.


Under Mac OS up to and including version 9.2.2, AFP is the only network protocol supported by default for file access on other computers. Under Mac OS X, AFP is one of many network protocols supported by default for the integration of remote file systems (in addition to SMB / CIFS or NFS ).

The AFP client on Mac OS (up to and including 9) shows an icon consisting of two opposing arrows in the upper left corner of the screen, which flashes when there is activity on connected volumes. In this way, the user is informed about possible waiting times.

Farallon marketed a solution in the early 1990s that consisted of an ISA bus card for connection to a LocalTalk network and corresponding software for PC-compatible DOS and Windows 3.1 . With their help one could access AFP servers.


The following server solutions from Apple can be used as dedicated servers:

AppleShare Server
runs on Mac OS up to version 8.1,
DDP support for transport only .
AppleShare IP Server
executable on Mac OS up to version 9.2.2,
DDP or TCP / IP support for transport.
AppleShare Pro
executable on A / UX ,
only DDP support for transport.
AFP file server from Mac OS X Server
DDP support for transport up to version 10.3 available, after that only IP.

AFP server implementations are also available from other manufacturers. For example, Microsoft offers Services for Macintosh as an optional service for the Windows server family , but this has not been actively maintained for years: Even Windows 2003 only speaks the outdated AFP level 2.2. Third-party manufacturers such as Acronis / Grouplogic with ExtremeZ-IP or Cyan Soft with MacServerIP, however, also offer modern AFP servers for Windows systems. Novell NetWare supplies an AFP-3 server.

With Netatalk and CAP there are also open source AFP servers for Unix-type operating systems.

All Mac OS versions from version 7.0 onwards can function as AFP servers, even though this functionality, known by Apple as " Personal File Sharing ", supports a maximum of ten connections for use as a peer-to-peer solution. Another disadvantage is the low transmission speed and the fact that the server computer is heavily loaded depending on the activity, which slows down work there.

The AppleTalk protocol stack

The AppleTalk protocols can be divided into several layers that form a protocol stack . The protocols can be classified in the ISO-OSI reference model as follows :

OSI layer AppleTalk protocol stack
4th          ATP AEP NBP RTMP
1 LocalTalk Ethernet -
Token Ring -


version Publication date Logs additional information
2.0 DDP
2.1 June 1991 DDP Adaptation to system 7 .
2.2 DDP, TCP
3.0 March 24, 2001 DDP, TCP Introduced with Mac OS X 10.0 (Cheetah). Support of UTF-8 , Unix file rights and for files larger than 2 GB.
3.1 August 23, 2002 DDP, TCP Bugfix release together with Mac OS X 10.2 (Jaguar); Implementation of Kerberos Version 2 (Kerberos V).
3.1+ October 24, 2003 DDP, TCP Introduced with Mac OS X Panther (10.3), with improved Kerberos support. Last version that can use the Datagram Delivery Protocol (DDP) from AppleTalk and is therefore compatible with very old versions of classic Mac OS (“ Macintosh System Software ” prior to System 7.5 ).
3.2 April 29, 2005 TCP Introduced with Mac OS X Tiger (10.4) and with support for ACLs and Extended Attributes .
3.2+ October 26, 2007 TCP Version of Mac OS X Leopard (10.5). Supplemented by functions for Time Machine .
3.3 August 28, 2009 TCP Introduced with Mac OS X Snow Leopard (10.6).
3.4 July 25, 2012 TCP No new functions, instead adaptation of the AFP error codes to POSIX . Introduced with OS X Mountain Lion (10.8).

See also


  • Sidhu, Andrews, Oppenheimer: Inside AppleTalk , 2nd, Addison-Wesley, 1999
  • Apple Computer Inc .: Inside Macintosh: Networking , 2nd, Addison-Wesley, 1994, Chapter 1 - Introduction to AppleTalk (online version)

Web links

Individual evidence

  1. Apple changes file sharing protocol , Florian Kurzmaier, June 12, 2013; Retrieved June 18, 2016.
  2. TCP and UDP ports used by Apple software products. Retrieved July 27, 2020 .
  4. Apple Developer: AFP Version Differences (English); Retrieved June 18, 2016.
  5. Netatalk Documentation, Chapter 3: Setting up Netatalk (English), Section “Authentication” under “UAMs supported by Netatalk”; Retrieved June 18, 2016.