The Philippine Long Distance Telephone Co. (PLDT) yesterday said it is congestion and not call barring that has resulted in interconnection problems with other phone companies.

The PLDT informed the National Telecommunications Commission that it is delaying its migration into Next Generation Network since the shift has resulted in internal congestion.

PLDT said that the company is conducting " load balancing" to address the congestion problems.

Load balancing , PLDT said, means decommissioning switches or facilities to address their congested trunks.

Bayan Telecommunication Inc., (Bayan) has complained to the NTC that it is having interconnection problems with the PLDT, meaning calls from Bayan phones do not get through PLDT lines.

PLDT said that the internal network congestion within the PLDT network and not call restrictions are the causes of inaccessibility issues experienced by carriers connected to PLDT network.

The Philippines Telegraph and Telephone Corp., (PT & T) also said PLDT is blocking voice calls from its network.

The company had asked the NTC to direct PLDT to cease from constricting or blocking all traffic from PT&T to PLDT subscribers in the "02" local exchange calling area.

PLDT said that it is barring calls from PT&T because of unpaid interconnection charges.

PLDT asked NTC to deny the petition of PT&T for lack of merit.

In December 2007, PLDT has tapped a European telecom company to assist them from the migration of its system to NGN.

"We have actually engaged with the advisory group of British Telecom to help us plan for the transition to NGN. They are here for about two months already advising us on their own experience in terms of their migration from legacy to NGN," Manuel V. Pangilinan, PLDT chairman earlier said.

NGN is the latest technology for voice and multimedia communications based on open architecture design made possible through Internet protocol (IP) technology.

PLDT had announced that it will spend about P7.7 billion to finance its NGN and broadband expansion.

PLDT will install 600,000 to 700,000 NGN lines nationwide from an initial rollout of 150,000 in 2005.

Pangilinan said the company expects NGN to have stronger contributions to its revenue by 2009.

The network congestion was also experienced by Philippine Telegraph & Telephone Corp. (PT&T) and Bayan Telecommunications Inc.