Constellations

Principle

PageBox architecture is designed to distribute presentation processing on a large number of machines hosting a PageBox agent whose our implementation is named JSPservlet.
There can be private set of PageBox used in Intranet or Extranet. There can also be public - Internet - PageBox sets we call constellations.
Ursa project aims to create such constellations on existing ASPs infrastructure.

Technical items

• Security
  1. Presentations run in Java 2 sandboxes with permissions granted by policy files.
     To be granted extra privileges they must be signed with a certificate delivered by a valid authority. These features are supported by the current JSPservlet/publisher implementation and do not require extra development.
  2. Presentation deployment uses HTTP over SSL. This feature is also supported by current implementation.
  3. Presentation publishing uses HTTP over SSL and allows identifying both the publisher (content provider) and the editor. This feature has to be developed.

  PageBox infrastructure relies on the use of certificates. CRL and Certificate Authority certificate can be checked on an LDAP server.

• Redirection and load balancing
  1. Implementation

     JSPservlet supports HTML static files as resources. The redirection relies on the ability of JSPservlet to parse these pages and change their HREF to point on other URLs.

  2. Load balancing

     JSPservlet uses round-robbin algorithm and a standard feature of Publisher.
     Publisher can be queried in HTTP for the list of subscribers for a given archive.

  3. Redirection

     A redirection on JSPservlets based on geographical criteria (where the user is querying from?) has to be implemented. It relies on DNS analysis and on whois.
     If the DNS name ends with a country code such as fr or kr, then the request is routed on JSPservlets installed in the same state.
     If the DNS name ends with com, net... then JSPservlet uses whois.

• Central servers invocation

  PageBox architecture includes the creation of VPN between PageBoxes and central systems to carry client/server requests.
  This mechanism is however incompatible with the non-intrusive approach of Ursa constellations.
  Therefore we recommend to use protocols relying on SMTP or HTTP for communication with central servers.
  SOAP is appropriate.
  You can also use RMI and CORBA protocols over HTTP. These protocols are proprietary but can provide better performance.

Constellations

Please contact support@pagebox.net if you want to know more or to participate to that initiative.

• Ursa Minor

  Test constellation.

  • No security enforced, no central administration.
    It doesn't mean you cannot install archives in a secured way, but that nothing prevents you to install without security.
• Ursa Major

  Production constellation.

  • Security enforced
  • Best effort administration
  • Fault tolerance mechanisms such as multiple repository support