Hello everyone,
What i suggest is that you guys join the project at http://whitelassi.dev.java.net and then subsequently subscribe to the mailing list users@whitelassi.dev.java.net
The projects that will be undertaken by the community members of this open source project will need to first understand the proposed programming model of the services that are going to be built. I will discuss the first service for this project in the coming posts.
Any service delivery platform requires a highly scalable, transactional, highly available and extensible programming model.
For satisfying the above mentioned requirements, the White Lassi open source project will base its development on the JSLEE (JSR 240) programming model.
I suggest that you all download the specification from the link given in the blogroll on the right hand side bar. Apart from the specification, also see the online tutorials about JSLEE from the SLEE-Tutorials tab of this blog: http://whitelassiblog.wordpress.com/slee-tutorials/
JSLEE is an event driven powerful architecture. An implementation of this standard exists in the form of the Mobicents open source project. The link for Mobicents can also be found from the sidebar. There is another implementation of the JSLEE standard that has been carried out by Open-cloud ( A new zealand based firm). However, it is not open source. However, we can use its documentation links for our understanding.
For new community members the orientation schedule will consist of the following phases:
A) Acquiring the domain knowledge of JSLEE programming practices and concepts.
B) Getting conversant with SIP and IMS SIP ( used as a signaling protocol)
I have mentioned SIP and IMS SIP seperately for a reason. This will be clarified later in this post.
A)JSLEE Programming model first steps
1) Browse the Mobicents JSLEE FAQs at http://www.mobicents.org-a.googlepages.com/faq.html
and the documentation at http://groups.google.com/group/mobicents-public/web/user-guide?pli=1
2) Download the specification (JSR 240) and get some idea of whats going on in the JSLEE programming model. (download link in blog sidebar)
3) To download the Mobicents binary, which comes bundled with the JBOSS application server (4.2.2 GA currently) from http://www.mobicents.org/jainsleedownload.html
JBOSS and Mobicents are open source and a part of Red Hat inc.
4) Download and install the eclipse plugin for JSLEE from: http://nchc.dl.sourceforge.net/sourceforge/mobicents/mobicents-eclipslee-1.2.3.BETA.zip
5) Browse through the example SBBs (Service Building Blocks) which come along with the distribution.
6) Join the Mobicents users forums at: http://forums.java.net/jive/forum.jspa?forumID=55
7) Apart from reading the specification, it is highly recommended that these links are read very carefully and thoroughly. They will provide precious information about the JSLEE model: https://developer.opencloud.com/devportal/display/OCDEV/Hints+and+Tips+for+Writing+Well+Performing+SLEE+Applications
and other links on this portal….it will be very useful.
For getting a hands-on with the SBBs, the best place is the Mobicents binary. It contains some very good examples for getting you started.
Service Building Blocks (SBBs) are a central concept of JSLEE and they contain the actual business logic of any application developed on top of JSLEE.
Any applications that we plan to build on top of JSLEE will be composed of numerous SBBs. The challenge lies in understanding the runtime environment of a SBB, how it functions, its dependancies and its best programming practices.
These steps are important for getting a reasonable grip on the programming subject matter.
B) Getting conversant with SIP and IMS SIP ( used as a signaling protocol)
The Session Initiation Protocol (SIP) is the protocol used for session setup, maintenance, and teardown. For getting an introduction to SIP, i believe these links will be valubale:
SIP is standardized by RFC 3261: www.faqs.org/rfcs/rfc3261.html
Moreover, if there is any SIP related doubt in RFC 3261 or otherwise, please put it on the mailing list of this project: users@whitelassi.dev.java.net
SIP as given in RFC 3261 is only VoIP (Voice over IP) SIP. But, in this open source endevour, we have to satisfy the requirements of the IMS(IP Multimedia Subsystem) customer.
IMS is essentially a wrapper over SIP. The IMS also uses SIP for session setup and teardown, but there are many more RFC’s that are defined as extensions to RFC 3261 for supporting IMS.
As IMS is being standardized by 3GPP, the standards can be found at:
http://www.3gpp.org/ftp/Specs/html-info/22-series.htm (Stage 1)
http://www.3gpp.org/ftp/Specs/html-info/23-series.htm (Stage 2)
and
http://www.3gpp.org/ftp/Specs/html-info/24-series.htm (Stage 3)
However it is not recommended to go through these standards as yet. RFC 3261 is most important to start with. In a subsequent blog post, where i will be describing our first service, I will provide a plan on how to tackle IMS domain knowledge in a concise and systematic way.
Remember, that if you understand RFC 3261 SIP, then IMS will be easy to understand..as it is TOTALLY based upon SIP.
I hope this information was useful and it has defined a logical path to move forward for any community member who wishes to join in this project.
If there are any questions/queries/confusions….please drop a comment here…and i will respond.
You can also drop me a mail at: abhatnagar192006@gmail.com
I will discuss our first MAJOR service in subsequent posts.
Best Regards
Aayush
