This is a short introduction using DCA WebServices offered by BiBiServ. If you're not familiar with using webservices in general you should have a closer look to our webservice related linklist.

If you've a closer look at the WSDL file describing the dca webservice, you can see two methods belonging together.

request and response
request_orig and response_orig

Bioinformatic programs often perform computation on large data sets and therefore require much CPU time. This can cause problems like http connection timeouts (usually after 5 minutes) during online usage. To avoid such problems when using dca WebService we use a technique called Request and Reply with polling based on BiBiWS. First the client side (e.g. your program) requests a dca job submitting the necessary data (parameter and data) and gets an id after the job is started. Afterwards the client can request the result by calling the corresponding response method with the id returned earlier. If the dca job is not finished, the user gets a status code with an enhanced description of current status back (see HOBIT status codes for more information).

request/request_orig
The request method (request/request_orig) gets two parameters as input - a parameter array with key/value pairs as described in the following table, a (multiple) sequence file in FASTA or SequenceML format - and returns either a unique id or in case of an error a fault message.

key	value	description
c	String - one of the following alternatives: pam250|pam160|blosum62| blosum45|blosum30|dna| rna|dnarna|unitcost	predefined substitution matrix (optional)
g	Boolean	penalize end gaps as internal gaps (default: free shift)(optional)
a	Boolean	use approximate cut positions (default: C-optimal positions) (optional)
b	0.0 ≤ Double ≤ 1.0	weight intensity (default: 0.0) (optional)
l	Double : 1 ≤ 30 ≤ 100	recursion stop size (default: 30) (optional)
w	Integer : ≥ 0	window size (default: 0) (optional)

response/response_orig
The response method expects the bibiid returned by an earlier request or request_orig call. It returns the results of the DCA computation in Fasta format or AlignmentML.

The example Perl client implementation is based on SOAP::Lite and combines request_orig and response_orig through active waiting.

The example Java client is based on Apache Axis and combined request and response through active waiting.