Lesson plan

Apache JServ Protocol

The Apache JServ Protocol (AJP) is a binary protocol that can proxy inbound requests from a web server through to an application server that sits behind the web server. AJP is a highly trusted protocol and should never be exposed to untrusted clients, which could use it to gain access to sensitive information or execute code on the application server. It also supports some monitoring in that the web server can ping the application server. Web implementors typically use AJP in a load-balanced deployment where one or more front-end web servers feed requests into one or more application servers. Sessions are redirected to the correct application server using a routing mechanism wherein each application server instance gets a name (called a route). In this scenario the web server functions as a reverse proxy for the application server. Lastly, AJP supports request attributes which, when populated with environment-specific settings in the reverse proxy, provides for secure communication between the reverse proxy and application server. AJP runs in Apache HTTP Server 1.x using the plugin and in Apache 2.x using , and proxy balancer modules together. Other web server implementations exist for: lighttpd 1.4.59, nginx, Grizzly 2.1, and the Internet Information Services. Web container application servers supporting AJP include: Apache Tomcat, WildFly (formerly JBoss AS), and GlassFish.

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Article summary

The Apache JServ Protocol (AJP) is a binary protocol that can proxy inbound requests from a web server through to an application server that sits behind the web server. AJP is a highly trusted protocol and should never be exposed to untrusted clients, which could use it to gain access to sensitive information or execute code on the application server. It also supports some monitoring in that the web server can ping the application server. Web implementors typically use AJP in a load-balanced deployment where one or more front-end web servers feed requests into one or more application servers. Sessions are redirected to the correct application server using a routing mechanism wherein each application server instance gets a name (called a route). In this scenario the web server functions as a reverse proxy for the application server. Lastly, AJP supports request attributes which, when populated with environment-specific settings in the reverse proxy, provides for secure communication between the reverse proxy and application server. AJP runs in Apache HTTP Server 1.x using the plugin and in Apache 2.x using , and proxy balancer modules together. Other web server implementations exist for: lighttpd 1.4.59, nginx, Grizzly 2.1, and the Internet Information Services. Web container application servers supporting AJP include: Apache Tomcat, WildFly (formerly JBoss AS), and GlassFish.

Key claims

  1. publication date: 1998-07-29 — source: Wikipedia · confidence 0.95
  2. release date: 1997-07-30 — source: Wikipedia · confidence 0.95

Discussion questions

  1. Summarise the article in your own words. Which single claim would you verify first, and why?
  2. The record states that the publication date is "1998-07-29". What evidence would count against this claim?
  3. The record states that the release date is "1997-07-30". What evidence would count against this claim?
  4. Which claim in this article is most likely to be revised as the sources update? How would you check its current status?
  5. If two sources disagreed about one of these facts, what would you need in order to trust one over the other?

Bibliography

No sources recorded.

Key claims and bibliography are generated from the same tracked claims and sources as the article page.