I am working on my Diploma thesis , which topic is GPRS Emulation software. This project is based on your OsmoBTS project . The idea is to delete/replace the hw-related primitives and features and redirect the whole traffic to the osmocomBB with modifications – this is the work of my colleague .
1st point:
My intention is to implement gprs part only. I have analyzed the BTS codes(especially Master, Jolly/l1sap_parts and Jolly/Trx
), i dont know which one will be most suitable to use, but I think the jolly/trx or jolly/l1sap_parts common part will be probably best choise . It implements more common functions in l1sap interface compared to the Master
code . Am I right ?
2nd point: I have analyzed the common code, and it is look like the main logic of the PCU(from the BTS side) is implemented in
pcu_sock.c and l1sap.c , where the l1sap implements the message parsing and sending to the l1_if of the BTS , and also initializes
gsmtap messages . So what I want to do is to create another socket application to connect with osmocomBB(with additional gprs
implementation) , which will send/receive the BTS messages from l1sap through our custom "l1 interface" to the osmocomBB phone("how simple") . The PCU part looks, that would not need any intervention. What do you think ?
The hardest part will be to achieve , the application will be able to run witout HW (in the case of TRX branch , the bts will be able to connect to "transmiter" ). Since i am now standing on the crossroad, i need advice to make the right
discision . Any suggestions and comments
are highly appreciated.
Dominik Tamaskovic