- From: David Booth <dbooth@w3.org>
- Date: Tue, 11 Mar 2003 11:22:39 -0500
- To: www-ws-arch@w3.org
At the end of our F2F meeting, I took an action to poll the working group on the many "synchronous" definitions that were proposed. This poll is not intended to decide on the definition of "synchronous" directly, but only to narrow the field. Once we have narrowed the field, I will try to make adjustments as needed to reach consensus on a common definition. HOW TO VOTE [Ballot form adapted from http://www.debian.org/vote/howto_vote ] Erase everything above the top "-=-=-=-" line and erase everything below the bottom "-=-=-=-" line. Do not erase anything between these lines. Indicate your TOP THREE CHOICES. In the brackets next to your most preferred choice, place a 1. Place a 2 in the brackets next to your next choice. Continue till you use 3 for your last choice. Leave other choices blank. Start with 1, don't skip any numbers, don't repeat. Then mail the ballot to: member-wsa-ballots@w3.org . DO NOT SEND YOUR BALLOT TO THE PUBLIC LIST. Just Replying to this message should work, but check the "To:" line. Don't worry about spacing of the columns or any quote characters (">") that your reply inserts. Ballots are due by the end of Thursday 13 March 2003. -=-=-=-=-=- Don't Delete Anything Between These Lines =-=-=-=-=-=-=-=- synchronous Ballot <FB-sync> (Don't remove this marker) [1-3] Choice ----------------------------------------------------------------------- [ ] geoff-1 (see definition below) [ ] frank-1 (see definition below) [ ] frank-2 (see definition below) [ ] dbooth-2 (see definition below) [ ] dbooth-1 (see definition below) [ ] ugo-2c (see definition below) [ ] daveo-1 (see definition below) [ ] daveo-2 (see definition below) [ ] moberg-1 (see definition below) [ ] assaf-3 (see definition below) [ ] cutler-1 (see definition below) [ ] ferris-1 (see definition below) [ ] mikec-1 (see definition below) [ ] walden-1 (see definition below) [ ] assaf-1 (see definition below) [ ] assaf-2 (see definition below) -=-=-=-=-=- Don't Delete Anything Between These Lines =-=-=-=-=-=-=-=- Anything else may be rejected by the vote counting program. You should see your vote in http://lists.w3.org/Archives/Member/member-wsa-ballots/ Only one vote per person, no more than one vote per account. ################################################################## ##################### Candidate Definitions ##################### ################################################################## Definition geoff-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Mar/0029.html A message exchange pattern (MEP) is a formal description of how messages are exchanged between two or more parties in support of some application purpose. The pattern may define a single message sequence, or may correspond to a "family" of sequences by including repeated or nested sequences. An MEP is synchronous if the specification of the message sequence(s) includes elements in which the transmission of a message is dependent on either (a) the reception of some other message(s), or (b) coordination based on a common clock. An MEP is asynchronous if it includes no such dependencies. ---- Definition frank-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Mar/0023.html [From from Communicating Sequential Processes] Synchronous A rendezvous of two activities is synchronous if they complete simultaneously. ---- Definition frank-2 http://lists.w3.org/Archives/Public/www-ws-arch/2003Mar/0023.html Synchronous activity An activity involved in a synchronous rendezvous may assume that the rendezvous is complete for both sides if it 's side completes. ---- Definition dbooth-2 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0455.html Synchronous interaction An interaction is synchronous if the parties are involved in the interaction at the same time and the interaction carries an expectation of immediate processing. A one-way interaction is synchronous if successful message delivery implies that the message either has been processed by the receiver or is actively being processed. A round-trip or more complex interaction is synchronous if the initiator pauses some of its processing to wait for the interaction's constituent messages to be processed. In a round-trip interaction, the request and response are often sent over the same communication channel. ---- Definition dbooth-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0222.html Property of an interaction whose results are directly following the interaction. An interaction between an initiator and a respondent is synchronous if the initiator blocks some further processing while it waits for a corresponding action, response or acknowledgement from the respondent. ---- Definition ugo-2c http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0386.html Asynchronous: A request/response interaction is said to be asynchronous when the request and response are chronologically decoupled. In other words, the client agent does not have to "wait" for the response once it issues the initial request. The exact meaning of "not having to wait" depends on the characteristics of the client agent (including the transfer protocol it uses). Examples include receiving the response on a different thread, on a different socket, on a different end-point, by polling the server, etc. Synchronous: The opposite of asynchronous. ---- Definition daveo-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0432.html synchronous a programmatic flow of control on the sender effectively does nothing but wait for a response after sending it's request ---- Definition daveo-2 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0432.html synchronous the request and response flow forwards and backwards over the same virtual connection between the sender and receiver. ---- Definition moberg-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0343.html A web service response is said to be synchronous iff it is returned using the same network connection used in sending the request to which it is a response. (This implies that only one URL would be needed for request-response MEP when the response is synchronous and uses a transfer protocol that has URLs. It also implies that the request and response occur within the interval of time that the network connection exists. Also, there is overhead in setting up only one TCP connection when TCP is used, and since we are talking about IP _connections_ that will be almost always the case.) A web service response is said to asynchronous iff it is returned using a network connection that is distinct from that used for sending the request to which it is a response. (Implications: Two URLs are needed to configure a request-response MEP when the response is ==>asynchronous. The response connection may occur while the request connection is still open or after it is closed. For TCP-based transfer protocols, two connection setups will be needed.) ---- Definition assaf-3 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0354.html A transport is synchronous iff the request is returned using the same network connection. ---- Definition cutler-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0358.html Synchronous: a request/response exchange that is correlated by virtue of a serialized, sequenced exchange of messages between requestor and respondant, typically over the same socket or stream. Asynchronous: a request/response exchange that is not synchronous, typically relying on some mechanism such as Message-ID within the messages to correlate the request and response messages. ---- Definition ferris-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0437.html synchronous message exchange (applies to oneway as well as request/response) requires that both sender and receiver, or initiator and respondant, processes are running/active at the same time as the exchange takes place. In the case of request/response, the exchange is synchronous if both sender and receiver remain in the running/active state for both the request and response. asynchronous message exchange (also applies to oneway or request response) does not require, but does not preclude, that both sender and receiver, or initiator and respondant, processes are running/active at the same time as the exchange takes place. It typcally requires some form of mediation between the sender and receiver such as a message queue. ---- Definition mikec-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0318.html (Taken from http://whatis.techtarget.com/definition/0,,sid9_gci213080,00.html ?) In program-to-program communication, synchronous communication requires that each end of an exchange of communication respond in turn without initiating a new communication. A typical activity that might use a synchronous protocol would be a transmission of files from one point to another. As each transmission is received, a response is returned indicating success or the need to resend. Each successive transmission of data requires a response to the previous transmission before a new one can be initiated. Synchronous program communication is contrasted with asynchronous program communication. ---- Definition walden-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0326.html Synchronous, then, places a constraint on a response such that the response must be received within a strictly or loosely defined time quantum (strict vs lax synchrony), or else the exchange fails. Asynchronous differs in that no amount of elapsed time signals the failure of the exchange. ---- Definition assaf-1 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0321.html An operation is synchronous if both service requester and service provider engage will always engage in that operation at the same time. ---- Definition assaf-2 http://lists.w3.org/Archives/Public/www-ws-arch/2003Feb/0321.html An interaction is synchronous if activities demarcated by that interaction will always be performed at the same time. [End] -- David Booth W3C Fellow / Hewlett-Packard Telephone: +1.617.253.1273
Received on Tuesday, 11 March 2003 11:22:55 UTC