DAS/2

The DAS/2 Protocol

About DAS/2

DAS/2 is intended to be a more flexible and powerful version of the original specification upon which the majority of servers are based, DAS/1. The two versions are not natively compatible. The DAS/2 code base consists of:

1. The DAS/2 specification
2. A publically accessible DAS/2 server implementation (open source code available from the GMOD project)
3. An open-source DAS/2 client implementation
4. An open-source client library and server validation suite

See DAS/2#CVS Access for details on retrieving code related to these projects.

DAS/2 History

DAS/2 diverged from from DAS/1 as a result of a variety of RFCs (Requests for Comment) received from some users and implementers of the spec. As of November 2006, the retrieval portion of the DAS/2 spec has stabilized. Implementers and service providers can rely on this for their DAS/2-based development efforts.

DAS/2 development officially commenced in May 2005 when funding for a 2-year NIH grant became available (the grant was actually approved in July 2004, but it took a while for NIH to decide the specific funding amount). The grant officially expired at the end of October 2007. Participating in the DAS/2 grant were Affymetrix, Cold Spring Harbor Lab, the European Bioinformatics Institute/Sanger Center, and Dalke Scientific.

Given that the DAS/2 specification is not backward compatible with the DAS/1 version, existing DAS software will continue to support DAS/1. A DAS proxy server is in development that will permit a DAS/1 server to be accessed by DAS/2 clients.

DAS/2 Clients

The following software packages operate as clients capable of interacting with servers supporting the DAS/2 protocol:

• IGB - Integrated Genome Browser - a DAS/2 reference implementation
• GBrowse - Generic Genome Browser

DAS/2 Servers

The following software packages operate as servers capable of providing data in response to queries conforming with the DAS/2 protocol:

• Biopackages DAS/2 server - a DAS/2 reference implementation
• Affymetrix Public DAS/2 server
• Huntsman Cancer Institute's DAS/2 server

DAS/2 Validation Suite

See Das2Validation.

Publishing and Discovery of DAS/2 sources

See DasRegistry

Global Sequence Identifiers

See GlobalSeqIDs

Feedback and Bug Reports

A general forum for advice on DAS/2-related issues is the discussion list.

To submit or view bug reports in DAS/2-related software, use one of the links below, depending on the affected component.

• DAS/2 Specification:
  • http://bugzilla.open-bio.org/
• Reference Server (GMOD Project - select category 'DAS2'):
  • http://sourceforge.net/tracker/?group_id=27707&atid=391291
• Reference Client (IGB):
  • http://sourceforge.net/tracker/?group_id=129420&atid=714744
• Validation Suite (Dasypus):
  • https://sourceforge.net/tracker/?group_id=138271&atid=740641

CVS Access

There are separate repositories for the DAS/2 specification, DAS/2 client and server reference implementations, and the validation suite. These are for developers only since they do not represent stable releases and may contain modifications that contain bugs. The one exception is the schema for the retrieval portion of the DAS/2 spec, which is now stable.

• DAS/2 spec:
  • :pserver:cvs@cvs.biodas.org:/home/repository/biodas
    • (login password="cvs", directory=das/das2, XML schema for retrieval spec: das2_schemas.rnc)
• DAS/2 Client reference implementation ("IGB")
• DAS/2 Server reference implementation (see das2 package)
• DAS/2 validation suite ("Dasypus")

See http://www.open-bio.org/wiki/SourceCode for general pointers about anonymous access to open-bio.org-hosted source code.