Challenges of fiber network

  Operators in many regions are bringing more fiber into their access network but they meet barriers in real field. One of the biggest barriers is the economics to install new fiber, especially under ground feeder fiber. The labor cost exceeds more than half of total capital expense to establish a fiber based access network in most of the developed countries. The establishment of fiber network with existing feeder fiber, without new fiber deployment, can reduce this barrier but the number of existing feeder fiber is limited and not enough in many cases to cover the bandwidth they need with today’s optical link technologies. Even though today’s TDM based PON saves feeder fiber with ratio of 32 or 64 by sharing a single feeder fiber, operators have to install new feeder fiber due to insufficient number of existing feeder fiber in many cases. Operators require new optical link technology to save feeder fiber and maximize the utilization of existing fiber

  WDM technology has been widely adopted to save the fiber in transport network but its high cost has prevented it from being adopted in access network where economy is crucial. A less expensive CWDM has been tried in several cases but unsuccessful due to its difficulties on management of color in mass deployment. WDM technology has to overcome both issues of economy and colorless operation to be adopted in access network

Economic Colorless WDM PON

  Corecess introduces an economic colorless WDM PON solution that is optimized for access network. This state-of-the art optical link technology ensures economy by removing the tunable laser diodes, the most expensive parts in legacy WDM equipment, and supporting the colorless operation by reusing the received wavelength. Multiple channels of Gigabit Ethernet, currently 16 channels, are supported over a single fiber. The bandwidth of 16 Gbps to a single node or curb is sufficient for any services of today and near future. Further more, it can support enough number of subscribers within a single node or curb when it is connected to Corecess’ last mile equipments. Operators can save the feeder fiber and secure the economy while implementing fiber based access network

The WDM PON line card in S5 PON OLT enables to transmit 16 different wavelengths in each carrying a GbE over single fiber from CO/Hub to RT/Node.  Those 16 wavelengths are de-multiplexed at node by multi-stage WDM filters. WDM filter is able to de-multiplex 4 or 8 GbE from ingress of multiplexed wavelengths.  The colorless WDM ONT or ONU offers dedicated 1GbE bandwidth to cooperate customer located within 20Km S5 PON OLT.  The S1 micro GEPON OLT placing after WDM filter in node enables to serve the over 1,000 users as well as extends the service range up to 40Km.  This micro GEPON is embedded with colorless media converter for uplink interface and provides 2 GEPON ports for subscriber. Each GEPON can be spitted up to 64 at most.  The last application is a similar architecture as of micoro GEPON OLT. But, using just λ Converter in remote node offers two outstanding advantage of centralized network management and seamless installation at current node environment since its dimension is as small as current optical transceiver and its power consumption is very low comparing with micro GEPON OLT

Corecess Advantage

Dramatic savings of CapEx and OpEx

  By maximizing feeder fiber utilization, most operators can save the capital expense from reducing the cost of new fiber deployment. Operators can implement fiber based access network with only existing feed fiber in many cases. Operating expense is minimized by adopting field-passives where no field support is required

Colorless Operation

  Colorless operation enables location free service and removes burden of inventory and management of color. Colorless operation is crucial when large number of optical links is managed in such case of access network.