IPTV technologies have come a long way in getting high-quality television to the home--but how does it get to the TV? The phone line (fiber or copper) connects to a home gateway. IPTV set-top boxes are connected to TVs. The usual connection between the gateway and the set-top boxes is 100 Mbps Ethernet. That's fine if the gateway is close to the TV -- a short Ethernet cable will do fine.
But many homes don't have a phone line close to the TV, so they need Category 5e cabling from one room to another. Most homes, especially in the US and Canada, have more than one TV, so Category 5e has to be run to a set-top box in each room. More Category 5e cabling is needed for PCs. That makes for a pretty expensive IPTV installation.
Using the coaxial cables that are already in the walls of the house is an attractive alternative. Coaxial cables run between all the TVs in the home. Coax is very well designed to support broadband communications--if cable or satellite broadcast television looks good on the TVs, the coax will probably carry high-speed data just fine.
Several companies have been working to develop technologies to move high-speed data over coax--an ideal solution for IPTV. We recently interviewed one of them on the phone to get a sense for the state of the art. Ted Archer is Director of Marketing at Coaxsys, a Silicon Valley company that has developed a complete product line for Ethernet over coax.
We asked Ted whether the Coaxsys products formed a "generalized home network" and he told us that product positioning depends on the market. Coaxsys believes phone companies, cable companies, satellite companies and system integrators need somewhat different products, and Coaxsys provides different products to meet the needs of each market.
Ted said "Telco IPTV needs a network which can carry IP video over the existing coax from a home gateway to set-top boxes" on top of each TV, and their "IPTV 7000" does just that. Coaxsys specs indicate that their IPTV 7000 units will operate at up to 104 Mbps over "250 foot adapter to adapter runs including splitters". Ted tells us that these are now deployed at "over sixty telcos for IPTV--the largest announced customer is Consolidated Communications," a 100-year-old local telco in Illinois, and "we're running lab trials and field trials with all the RBOCs."
He said the reason Coaxsys had focused on TV applications is that "PCs are mostly taken care of by wireless" and coax usually does not run to PC locations. He said Coaxsys equipment is "being used by other companies for non-IPTV networking" and they are selling equipment to members of CEDIA who will pull coax to operate video and data over the same coax.
"Cable operators have different needs and demands" says Ted, and other companies "don't focus enough on the needs of specific markets." Unlike the IPTV products which use the entire spectrum on the coaxial cable, Coaxsys' TVnet/C product for cable operators carries high-speed data over coax in areas of the spectrum outside that used to carry cable services, so it does not interfere with existing video services.
Coaxsys has specific products for other market segments as well, including satellite providers and system installers. It also has a model designed specifically for the Amino set-top boxes which have become very popular in IPTV deployments.
Coaxsys recently announced they will show a "next-generation" 200 Mbps product at the upcoming Consumer Electronics Show.
For More Information We have written for nearly three years about home networking over existing coaxial cable, especially for TV applications: