In addition to Ericsson, U.S. telecoms equipment maker Amdocs is also interested in the BSS unit, which provides billing and charging systems for telecoms operators, Dow Jones quoted a source familiar with the matter saying.
A source familiar with the situation told Reuters the unit was among assets NSN was considering selling, but could not confirm a deal was imminent.
Ericsson and NSN, a joint venture between Nokia Oyj and Siemens AG, declined to comment. Amdocs was not immediately available for comment.
NSN is in the middle of a slimming programme that will also cut 17,000 of the group's workforce or almost a quarter of the total in an effort to improve its finances.
Sweden-based Ericsson has been expanding rapidly in BSS and operations support systems (OSS), last year buying Telcordia in the United States for $1.1 billion.
A recent survey by consultancy Gartner ranked Ericsson top globally by revenues in OSS and BSS services, including sales acquired with Telcordia.
NSN made a profit of 27 million euros on a non-IFRS basis in the second quarter on sales of 3.3 billion.
Copyright Thomson Reuters 2012