NEW services provided via the national broadband network could make it harder for the Australian Federal Police to track people downloading and sharing child pornography.

The bipartisan Parliamentarians Against Child Abuse and Neglect group was briefed yesterday by the AFP on possible services that could be part of the NBN. The officers told the group that the increase of service providers and different modes available would make it harder for police to monitor suspects.

''Due to there being a large number of service providers currently and emerging in the telecommunications industry, this has the potential to increase the difficulty for law enforcement to obtain telecommunications data,'' an AFP spokeswoman said.

The NBN will allow companies to ''bundle'' multiple services including TV, internet and telephones on to one line, which worries the AFP. Senator Bill Heffernan, who is a member of the bipartisan group, said he was deeply concerned that the work of the federal police and international agencies to track offenders could be undone.

''One of the great challenges is going to be to come to terms with the anonymity that comes with the NBN. It will be a challenge for both the child protection units and the network of the global police agencies,'' he said.

''There will be no need to have the details of who you rang, and when you rang and what you downloaded, because there will be just a fee and you'll do whatever you like for that fee … That will be fraught with danger in coming to terms with what is a flourishing child porn business.''

A spokesman for Broadband Minister Stephen Conroy said, ''NBN Co and the department are working with the AFP and other national security and law enforcement agencies to ensure any potential criminal exploitation is minimised in the design and operation of the NBN.''