Goodbye ASI — Charter Communications Inc. is on the way to an all-gigabit Ethernet transport scheme for its video-on-demand rollouts, both past and future.
The MSO last week said nine new VOD markets will all be powered by the newer high-capacity technology, and it is in the process of converting six existing VOD systems from asynchronous serial interface (ASI) to GigE.
The nine new markets in which VOD will launch by year-end are: Allendale, Mich.; Fond du Lac, Jonesville and Madison, Wis.; Jackson, Kingsport and Manchester, Tenn.; Kennewick, Wash.; and St. Peters, Mo.
Charter will use Concurrent Computer Corp.'s MediaHawk Broadband VOD System to serve up content in Allendale, St. Peters, Fond du Lac, Janesville, and Madison. That brings Concurrent's Charter deployment to 11 markets.
In the four remaining new markets, Charter will use nCUBE Corp.'s gigabit Ethernet VOD delivery system and n4X enhanced video server to fire off the content. That will bring nCUBE's Charter deployment tally to 10 systems.
The advantage of Gig E comes from its greater transport capacity, which cuts down on the number of servers needed to power a VOD rollout.
Operators design VOD systems by estimating the amount of contention, or the percentage of total subscribers who are linked to a VOD server at any given time.
MSOs often shoot for 3 percent to 5 percent rate of contention, and that dictates how many servers are needed to support a rollout.
"By doing Gig E and standard gigabit Ethernet switching, we don't have to buy as many servers," Charter vice president of engineering and technology Don Loheide said. "So we can deploy our service groups to support, right now, 3 percent peak contention for movies-on-demand. What we are seeing on the server side is any one server is not exceeding 1½ percent."
Gigabit Etherent also makes it easier to centralize VOD servers, and that process helps save Charter money.
While all 10 markets using nCUBE gear will employ GigE from the start, the existing Concurrent markets started out using ASI. In its VOD deal with Concurrent, Charter stipulated that when the migration technology was available, those markets would move to GigE.
That's now happening in the existing markets, including Asheville, N.C.; Duluth, Ga.; Greenville/Spartanburg, S.C.; Hickory, N.C.; Slidell, La.; and St. Louis.
The five new Concurrent markets will roll out with GigE.