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diff --git a/apps/Gateway/README b/apps/Gateway/README deleted file mode 100644 index 23d0336d77b..00000000000 --- a/apps/Gateway/README +++ /dev/null @@ -1,140 +0,0 @@ -OVERVIEW - -This directory contains source code for an application-level -Communication Gateway implemented with ACE. This prototype was -developed in my cs422 OS class at Washington University in 1994. The -Gateway has recently been updated to illustrate the use of Event -Channels, which forward events from Suppliers to Consumers in a -distributed system. - -You can get a paper that explains the patterns used in this -implementation at the following WWW URL: - -http://www.cs.wustl.edu/~schmidt/TAPOS-95.ps.gz - ----------------------------------------- - -DIRECTORY STRUCTURE - -There are 2 directories: - -1. Gateway - - This directory contains the source code for the - application-level Gateway process, gatewayd. The gatewayd - routes event messages between Peers. By default, the gatewayd - plays the Connector role and initializes itself by reading the - proxy_config and consumer_config files: - - 1. The proxy_config file establishes the "physical - configuration" of the Consumer and Supplier proxies. This - file tells the Gateway what connections to establish with - particular hosts using particular ports. - - 2. The consumer_config file establishes the "logical - configuration." This file tells the Gateway how to forward - data coming from Suppliers to the appropriate Consumers. - - The application Gateway generally should be started after all - the Peers described below, though the process should work - correctly even if it starts first. - -2. Peer - - This directory contains the source code for the Peer process, - peerd. There are typically many Peers, which act as suppliers - and consumers of event messages that are routed through the - gatewayd. - - To do anything interesting you'll need at least two Peers: one - to supply events and one to consume events. In the - configuration files, these two types of Peers are designated - as follows: - - 1. Supplier Peers (designated by an 'S' in the Gateway's - proxy_config configuration file). These Peers are - "suppliers" of events to the Gateway. - - 2. Consumer Peers (designated by an 'C' in the Gateway's - proxy_config file). These Peers are "consumers" of events - forwarded by the Gateway. Forwarding is based on the - settings in the consumer_config configuration file. - ----------------------------------------- - -HOW TO RUN THE TESTS - -To run the tests do the following: - -1. Compile everything (i.e., first compile the ACE libraries, then - compile the Gateway and Peer directories). - -2. Edit the consumer_config and proxy_config files as discussed - above to indicate the desired physical and logical mappings - for Consumers and Suppliers. - -3. Start up the Peers (peerd). You can start up as many as you - like, as per the proxy_config file, but you'll need at least two - (i.e., one Supplier and Consumer). I typically start up each Peer - in a different window on a different machine, but you can run them - on the same machine as long as you pick different port numbers. - The Peers will print out some diagnostic info and then block - awaiting connections from the Gateway. - - If you want to set the port numbers of the Peers from - the command-line do the following: - - a. Change the svc.conf file in the ./Peer/ directory to - another name (e.g., foo.conf). This will keep the - program from starting up with the svc.conf file - (which dynamically links in the Peers and uses the -a option to - set the port). - - b. Then run the peers in different windows as - - # Window 1 (Supplier) - % peerd -a S:10003 - - # Window 2 (Consumer) - % peerd -a C:10004 - - etc. Naturally, you can also edit the svc.conf file, but that - may be more of a pain if you've got a network filesystem and - all your hosts share the same svc.conf file. - -4. Start up the Gateway (gatewayd). This will print out a bunch of - messages as it reads the config files and connects to all the Peers. - By default, the Gateway is purely reactive, i.e., it handles - Consumers and Suppliers in the same thread of control. However, - if you give the '-t OUTPUT_MT' option the Gateway will handle all - Consumers in separate threads. If you give the '-t INPUT_MT' option - the Gateway will handle all Suppliers in separate threads. If you - give the '-t INPUT_MT|OUTPUT_MT' option both Consumers and Suppliers - will be handled in the separate threads. - - Assuming everything works, then all the Peers will be connected. - If some of the Peers aren't set up correctly, or if they aren't - started first, then the Gateway will use an exponential backoff - algorithm to attempt to reestablish those connections. - -5. Once the Gateway has connected with all the Peers you can send - events from Supplier Peers by typing commands in the Peer window. - This Supplier will be sent to the Gateway, which will forward the - event to all Consumer Peers that have "subscribed" to receive these - events. - - Note that if you type ^C in a Peer window the Peer will shutdown - its handlers and exit. The Gateway will detect this and will start - trying to reestablish the connection using the same exponential - backoff algorithm it used for the initial connection establishment. - -7. When you want to terminate a Gateway, just type ^C or type any - characters in the ./gatewayd window and the process will shut down - gracefully. - -Please let me know if there are any problems, questions, or -suggestions for improvement. - - Doug - - schmidt@cs.wustl.edu |