The cost of fiber has dropped, making it sensible to push deeper into the network as close as possible to the subscriber. The reality for cable operators, however, is that they have an existing HFC network in place, and DOCSIS 3.1 will be the enabler for widespread offerings of gigabit speeds. While the transition to DOCSIS 3.1 offers a number of technical challenges, operators also must keep in mind the effect on OSS/BSS platforms and the overall impact on the physical network of ramping up to speeds that approach and surpass the gigabit mark, said Stephane Bourque, CEO of Incognito Software Systems.
"It is more than just cabling and so forth. There is a cascading effect. Once you deliver gigabit to enterprises or homes, if the service is a commercial success, will the rest of the infrastructure support the speeds?" Bourque said, noting that if the network is stressed, the service may drop down to 100 Mbps or lower, and the operator will fail to deliver the promised gigabit broadband.
Modeling can help project what traffic patterns will look like at a future time and avoid issues caused by a gigabit service ramping up too fast. "Some problems are caused by people not doing their homework. They might have upgraded the CPE, CMTS and plant, but realize (too late) that the service is too popular and they needed more node splits, more CMTSs, or a move to CCAP," Bourque said. "(Operators) can no longer just do hardware. They have to do software as well."
Operators can use modeling to not only target network infrastructure upgrades, but also to fine tune marketing strategy by predicting which customers are the best candidates for subscribing to gigabit speeds. A campaign could be directed toward those households or businesses. If it is determined 19% of the population are likely to take the gigabit service, for example, the operator then can look at the stress that would place on the network and determine whether the marketing efforts should be expanded. "What if they converted 50%? What would the network look like? There are a lot of scenarios they can play with to see if they should suggest gigabit," Bourque said.
As for provisioning, although there is DOCSIS provisioning over EPON (DPoE), there are flavors of fiber that are much different beasts than HFC. For example, pure GPON knows nothing about DOCSIS, and so the activation capability has to be built inside the OSS. "What has slowed down fiber deployment is having to go to system 1 to provision HFC and system 2 to provision fiber," Bourque said.
Integration of the two systems is the goal in order to make things as easy as possible for the customer service representative and the consumer. "If the customer happens to be serviced by fiber or DOCSIS, it doesn't matter to the CSR or subscriber. The key point is being able to provide these services quickly and transparently," Bourque said.
Training is another factor to consider when moving to higher speeds either via fiber or DOCSIS 3.1. The technicians and CSRs need to be instructed on the new management and provisioning tools as well as installation techniques for DOCSIS 3.1 and fiber. "Operators will have to retrain installers or hire a new set to complete the workforce they already have. There is a lot to think about when going to gigabit," Bourque said.