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Your Trail jndi > directory > jndi > axis > SOAP Table of Contents [show]     1 Introduction     2 SOAP Message Construct     3 SOAP Processing Model     4 SOAP Extensibility Model     5 SOAP Authentication       5.1 Protocol-Level         5.1.1 Security tokens         5.1.2 Signatures         5.1.3 Encryption         5.1.4 Security timestamps         5.1.5 Further reading       5.2 Application-Level         5.2.1 Security header with username password information Keywords .NET, Axis, CORBA, Java RMI, W3C Copyright Information This article is licensed under GNU Public License. Contact webmasters for more information on copyright issues. 1 Introduction SOAP is short for Simple Object Access Protocol. It is a protocol for communication between applications SOAP is a format for sending messages and it is designed to communicate via Internet. It is based on XML, therefore it is platform independent and language independent. Right now, SOAP is being superceded by Axis: the Apache web service engine. [JW] Here is the definistion from W3C: "SOAP Version 1.2 (SOAP) is a lightweight protocol intended for exchanging structured information in a decentralized, distributed environment. It uses XML technologies to define an extensible messaging framework providing a message construct that can be exchanged over a variety of underlying protocols. The framework has been designed to be independent of any particular programming model and other implementation specific semantics. Two major design goals for SOAP are simplicity and extensibility SOAP attempts to meet these goals by omitting, from the messaging framework, features that are often found in distributed systems. Such features include but are not limited to "reliability", "security", "correlation", "routing", and "Message Exchange Patterns" (MEPs). While it is anticipated that many features will be defined, this specification provides specifics only for two MEPs. Other features are left to be defined as extensions by other specifications." There are already many remote procedure call techniques such as CORBA, .NET, Java RMI, etc. However, SOAP is different because it is over HTTP, therefore, it is supported by almost all web hosts, and SOAP traffic is allowed to go through many hosts where other RPC traffic are blocked. 2 SOAP Message Construct A SOAP message is wrapped in a pair of <envelope> XML tags. Here is an example message from the W3C SAP recommendations: <env:Envelope xmlns:env="http://www.w3.org/2003/05/soap-envelope"> <env:Header> <n:alertcontrol xmlns:n="http://example.org/alertcontrol"> <n:priority>1</n:priority> <n:expires>2001-06-22T14:00:00-05:00</n:expires> </n:alertcontrol> </env:Header> <env:Body> <m:alert xmlns:m="http://example.org/alert"> <m:msg>Pick up Mary at school at 2pm</m:msg> </m:alert> </env:Body> </env:Envelope> This message shows "a sample notification message expressed in SOAP. The message contains two pieces of application-defined data not defined by this specification: a SOAP header block with a local name of alertcontrol and a body element with a local name of alert . In general, SOAP header blocks contain information which might be of use to SOAP intermediaries as well as the ultimate destination of the message. In this example an intermediary might prioritize the delivery of the message based on the priority and expiration information in the SOAP header block. The body contains the actual message payload, in this case the alert message."[W3C] An envelope XML element has a local name Envelope and a name space "http://www.w3.org/2003/05/soap-envelope". and a set of namespace qualified attribute information items (e.g., encodingStyle). A SOAP envelope can contain an optional Header element information item and a mandatory Body element information item. A SOAP header element has a name "Header" and namespace "http://www.w3.org/2003/05/soap-envelope". It may contain the following attributes: encodingStyle, role, mustUnderstand, and relay. A SOAP body provides a mechanism for transmitting information to an ultimate SOAP receiver. A body element has a name "Body" and namespace "http://www.w3.org/2003/05/soap-envelope". The body element may have an optional encodingStyle attribute. A SOAP fault is used to carry error information within a SOAP message. The Fault element information item has a local name of Fault, and a namespace name of "http://www.w3.org/2003/05/soap-envelope". The fault element has a mandatory Code element information item, a mandatory Reason element information item, an optional Node element information item, an optional Role element information item, and an optional Detail element information item. 3 SOAP Processing Model SOAP provides a distributed process model which assumes a SOAP message has *one* sender and *one* ultimate receiver, with zero or multiple intermediate nodes. A SOAP node is identified by a URI. Each node may have one or more roles. For example, http://www.w3.org/2003/05/soap-envelope/role/ultimateReceiver is the ultimateReceiver role. Based on its roles and message content, a node may send, replay, or consume a message. 4 SOAP Extensibility Model A SOAP feature is an extension of the SOAP messaging framework. Although SOAP poses no constraints on the potential scope of such features, example features may include "reliability", "security", "correlation", "routing", and message exchange patterns (MEPs) such as request/response, one-way, and peer-to-peer conversations.[W3C] 5 SOAP Authentication The SOAP specification doesnot specify features such as security, therefore, it is the reponsibility of web service providers to guarantee that consumers of a web service are who they claim they are. There are multiple mechanisms to authenticate a SOAP web service consumer. 5.1 Protocol-Level 5.1.1 Security tokens Security tokens can be inserted into SOAP headers to support authentication. Example tokens are: user token, binary token, etc. We could also say that "security header with username/password" is a special kind of security token. [OASIS] 5.1.2 Signatures SOAP headers may contain a signature field which helps the service provider to make sure that the message is actually from a specific consumer and the message has not been altered during transition. [OASIS] Here is a library from apache for generating signatures: http://xml.apache.org/security/index.html 5.1.3 Encryption Messages can be encrypted so that nobody else but the service consumer and provider have access to the message content. Note that if you are using SSL connection, the whole message is automcally encrypted. [OASIS] 5.1.4 Security timestamps A security timestamp can be used to prevent "replay" attacks. [OASIS] [SOAPCLIENT] 5.1.5 Further reading Here is a good collection of SOAP related standards, mostly security-related. 5.2 Application-Level 5.2.1 Security header with username password information Client software put username/password in the header fields of a SOAP message, thereby the service can authenticate the client software. [CP] [OASIS] Comments References [CP] http://www.codeproject.com/cs/webservices/authforwebservices.asp [JW] http://www.javaworld.com/javaworld/jw-01-2002/jw-0125-axis.html [OASIS] http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-soap-message-security-1.0.pdf [SOAPCLIENT] http://soapclient.com/standards.html [W3C] SOAP Recommendations V.E.R.A Acronyms Simple Object Access Protocol (W3C, XML, HTML) (search time: 27.869 msec) City Data Buffalo Soapstone CDP, Alaska: Check out what google has to say about Buffalo Soapstone CDP, Alaska Total households 233, total housing units: 266 Land area: 22.582877 square miles, water area 0.005905 miles Latitude: NORTH 61.690168, longitude: WEST 149.12420 MAP Population:699, male 378 female 321 Races in Buffalo Soapstone CDP, Alaska: White/Non-Hispanic (88.56%) Hispanic (1.57%) Asian (0.43%): Asian-Other(0.29%) Japanese(0.14%) Black (0.29%) Soap Lake, Washington: Check out what google has to say about Soap Lake, Washington Total households 778, total housing units: 996 Land area: 1.208487 square miles, water area 0.000000 miles Latitude: NORTH 47.388341, longitude: WEST 119.48761 MAP Population:1733, male 822 female 911 Races in Soap Lake, Washington: White/Non-Hispanic (83.73%) Hispanic (11.77%) Black (0.87%) Asian (0.23%): Asian-Other(0.17%) Chinese(0.06%) (search time: 241.126 msec) Webster Unabridged Soap (?), n. [OE. sope, AS. sāpe; akin to D. zeep, G. seife, OHG. seifa, Icel. sāpa, Sw. s&?;pa, Dan. s&?;be, and perhaps to AS. sīpan to drip, MHG. sīfen, and L. sebum tallow. Cf. Saponaceous.] A substance which dissolves in water, thus forming a lather, and is used as a cleansing agent. Soap is produced by combining fats or oils with alkalies or alkaline earths, usually by boiling, and consists of salts of sodium, potassium, etc., with the fatty acids (oleic, stearic, palmitic, etc.). See the Note below, and cf. Saponification. By extension, any compound of similar composition or properties, whether used as a cleaning agent or not. &fist; In general, soaps are of two classes, hard and soft. Calcium, magnesium, lead, etc., form soaps, but they are insoluble and useless. The purifying action of soap depends upon the fact that it is decomposed by a large quantity of water into free alkali and an insoluble acid salt. The first of these takes away the fatty dirt on washing, and the latter forms the soap lather which envelops the greasy matter and thus tends to remove it. Roscoe & Schorlemmer. Castile soap, a fine-grained hard soap, white or mottled, made of olive oil and soda; -- called also Marseilles, or Venetian, soap. -- Hard soap, any one of a great variety of soaps, of different ingredients and color, which are hard and compact. All solid soaps are of this class. -- Lead soap, an insoluble, white, pliable soap made by saponifying an oil (olive oil) with lead oxide; -- used externally in medicine. Called also lead plaster, diachylon, etc. -- Marine soap. See under Marine. -- Pills of soap (Med.), pills containing soap and opium. -- Potash soap, any soap made with potash, esp. the soft soaps, and a hard soap made from potash and castor oil. -- Pumice soap, any hard soap charged with a gritty powder, as silica, alumina, powdered pumice, etc., which assists mechanically in the removal of dirt. -- Resin soap, a yellow soap containing resin, -- used in bleaching. -- Silicated soap, a cheap soap containing water glass (sodium silicate). -- Soap bark. (Bot.) See Quillaia bark. -- Soap bubble, a hollow iridescent globe, formed by blowing a film of soap suds from a pipe; figuratively, something attractive, but extremely unsubstantial. This soap bubble of the metaphysicians. J. C. Shairp. -- Soap cerate, a cerate formed of soap, olive oil, white wax, and the subacetate of lead, sometimes used as an application to allay inflammation. -- Soap fat, the refuse fat of kitchens, slaughter houses, etc., used in making soap. -- Soap liniment (Med.), a liniment containing soap, camphor, and alcohol. -- Soap nut, the hard kernel or seed of the fruit of the soapberry tree, -- used for making beads, buttons, etc. -- Soap plant (Bot.), one of several plants used in the place of soap, as the Chlorogalum pomeridianum, a California plant, the bulb of which, when stripped of its husk and rubbed on wet clothes, makes a thick lather, and smells not unlike new brown soap. It is called also soap apple, soap bulb, and soap weed. -- Soap tree. (Bot.) Same as Soapberry tree. -- Soda soap, a soap containing a sodium salt. The soda soaps are all hard soaps. -- Soft soap, a soap of a gray or brownish yellow color, and of a slimy, jellylike consistence, made from potash or the lye from wood ashes. It is strongly alkaline and often contains glycerin, and is used in scouring wood, in cleansing linen, in dyehouses, etc. Figuratively, flattery; wheedling; blarney. [Colloq.] -- Toilet soap, hard soap for the toilet, usually colored and perfumed. Soap (?), v. t. [imp. & p. p. Soaped (?); p. pr. & vb. n. Soaping.] 1. To rub or wash over with soap. 2. To flatter; to wheedle. [Slang] (search time: -639.031 msec) English-Chinese soap [soup] ·ÊÔí,°¢ÚÄÒÔ·ÊÔíÏ´,°¢ÚÄ (search time: 374.262 msec)