Broadband access continues to spread, but its growth rate was sharply curtailed in the second quarter of the year, according to Broadbandtrends.com.

Broadband subscriber net additions fell 30 percent from the previous quarter, with both cable modem and DSL slipping off significantly. The total additions of 2.1 million subscriber adds brought the total North American number to 45.4 million.

In the U.S., DSL had a slight edge over cable modems, adding 935,000 net subs to cable’s 880,000 total. But cable still has 56% of the broadband market in North America. The slower growth was attributed to the end of the school year, when college students turn off their service for the summer.

Broadband penetration in the U.S. is now 34% compared with 53% in Canada, where the split between DSL and cable modems is more even. Total net additions of subscribers in Cancada was just over 220,000 for the quarter, with DSL adding 130,000 net subs and cable adding 90,000.

Comcast remains the largest North American broadband provider, followed by SBC, Time Warner Cable, Verizon, BellSouth, Cox Communications, Bell Canada and Charter Communications. Rounding out the Top 10 were Cablevision and Adelphia.

Teresa Mastrangelo, broadbandtrends.com analyst, is predicting acceleration in broadband demand for the third quarter, because of the recent round of price cuts and service additions. Total broadband subscribers in North America should hit 50 million by the end of 2005, she is predicting.