Digital Audio Access Protocol
The DAAP protocol was originally introduced in iTunes version 4.0. Initially, Apple did not officially release a protocol description, but it has been reverse-engineered to a sufficient degree that reimplementations of the protocol for non-iTunes platforms have been possible.
A DAAP server is a specialized HTTP server, which performs two functions. It sends a list of songs and it streams requested songs to clients. There are also provisions to notify the client of changes to the server. Requests are sent to the server by the client in form of URLs and are responded to with data in application/x-dmap-tagged mime-type, which can be converted to XML by the client. iTunes uses the ZeroConf (also known as Bonjour) service to announce and discover DAAP shares on a local subnet. The DAAP service uses TCP port 3689 by default.
DAAP is one of two media sharing schemes that Apple has currently released. The other, Digital Photo Access Protocol (DPAP), is used by iPhoto for sharing images. They both rely on an underlying protocol, Digital Media Access Protocol (DMAP).
Early versions of iTunes allowed users to connect to shares across the Internet, however, in recent versions only computers on the same subnet can share music (workarounds such as port tunneling are possible). The Register speculates that Apple made this move in response to pressure from the record labels. More recent versions of iTunes also limit the number of clients to 5 unique IP addresses within a 24-hour period.
Beginning with iTunes 4.2, Apple introduced authentication to DAAP sharing, meaning that the only clients that could connect to iTunes servers were other instances of iTunes. This was further modified in iTunes 4.5 to use a custom hashing algorithm, rather than the standard MD5 function used previously. Both authentication methods were successfully reverse engineered within months of release.
With iTunes 7.0, a new 'Client-DAAP-Validation' header hash is needed when connecting to an iTunes 7.0 server. This does not affect third-party DAAP servers, but all current DAAP clients (including official iTunes before iTunes 7.0) will fail to connect to an iTunes 7.0 server, receiving a '403 Forbidden' HTTP error. The iTunes 7.0 authentication traffic analysis seem to indicate that a certificate exchange is performed to calculate the hash sent in the 'Client-DAAP-Validation' header.
As of October 13, 2018, the iTunes 7.0+ DAAP authentication still hasn't been reverse engineered, so no third-party application can stream from servers running iTunes software (from 7.x, all the way up to and including version 11.x).
|Name||Platform: Desktop||Platform: Portable||Platform: Devices/Other||Platform: TVs||Development status|
|iOS Music app (formerly iPod app)||iOS (by setting: password on Settings, then More>Shared), since iOS 4.3||Native|
|Amarok||Windows, Mac, Linux||Active|
|Banshee||Windows, Mac, Linux||Active|
|Crossfire||Cross-platform Ajax-based Firefly client, with multiple browser support
Safari (inc. iOS), Nokia, Opera, IE, Chrome
|DAAP Media Player||Windows Phone 8||Active|
|FireflyClient||Independent (uses Java)||Dormant|
|Get it together||Any Java supported platform||Dormant|
|iTunes||Windows, Mac||iOS||Apple TV||Native|
|LimeWire||Windows, Mac, Linux||Active|
|One2OhMyGod||Any Java supported platform||Dormant|
|Roku Soundbridge and Radio||Roku||Dormant|
|Songbird||Windows, Mac, Linux (unsupported)||Dormant, via plugin for 1.8.0|
|Silverplay||Only Silverlight required||Active|
|Simple DAAP Client||iOS||Dormant|
|Winamp with ml_daap plugin||Windows||Winamp discontinued on 12/20/2013; ml_daap dormant, depends on Apple Bonjour support for Windows|
|XBMC||Windows, Mac, Linux||XBMC Live iPad||Apple TV (2nd generation) only, and some others||Active|
|Name||Operating system||Development status|
|Firefly Media Server (mt-daapd)||Yes||Yes||Yes||FreeBSD||Dormant|
|spydaap DAAP server (python)||Yes||Yes||Yes||FreeBSD||Dormant|
|FreeNAS and NAS4Free||No||No||No||FreeBSD||Active|
|Wild Media Server (UPnP, DLNA, HTTP)||Yes||Yes||Yes||No||Active|
- List of software using Digital Audio Access Protocol
- Digital Audio Control Protocol
- Remote Audio Output Protocol
Notes and references
- "Unofficial DAAP protocol documentation" Archived 2012-02-22 at the Wayback Machine. by Daniel Garcia, retrieved December 2, 2006
- "Well Known Port Numbers" by IANA, November 30, 2006, retrieved December 2, 2006
- "Apple halts iTunes' Internet sharing ability" by Tony Smith, The Register, May 28, 2003, retrieved August 31, 2006
- "iTunes 4.5 Authentication Cracked". April 29, 2004. Retrieved March 12, 2007.
- "daap with iTunes 7 doesn't work correctly". Launchpad bug tracker. 2006-09-28.