Automating Fiber Optic Cross-Connect

FTTH Access Networks

A Fiber-to-the-Home (FTTH) access network defines fully optical access networks that connect the central office (CO) to the customer premises equipment (CPE). Operators can deploy FTTH networks in either Point-to-Point (P2P) or Point-to-Multipoint Passive Optical Network (PON) topologies.

Regulators and governments have set new rules to create a more competitive environment that will allow affordable, high performance broadband communication services for everybody. To this end, regulators (mainly in Europe) compel operators to implement multi-operator network architecture in FTTH networks as it is more cost effective than single-operator architecture. In a multi-operator network architecture, several operators deploy their fiber cables to an outside plant concentration point (sharing point) located close to the homes being served. From this sharing point, fibers are distributed to the homes via an optical distribution frame (ODF), with a single fiber dedicated to each customer’s home (home pass). This fiber is connected to a specific CPE upon the customer’s subscription to a service.

For P2P, the infrastructure fibers are distributed to the homes via an optical distribution frame (ODF) located either in the CO or in the street cabinet. Every end-user is connected via dedicated fiber. In the Point-to-Multipoint PON topology, a single fiber is shared by several end-users. In this topology, each fiber is connected to an optical line terminal (OLT) unit on the CO side that from there is run to an optical passive splitter box where it is distributed to optical network termination (ONT) units on subscriber's premises. Splitter boxes are placed at access nodes situated close to the user in street cabinets, manholes, or in a data sharing room usually located in the basement of the subscriber’s building.

Why Automate Optical Distribution Frames?

An optical distribution frame (ODF) interconnects feeder cable on the operator’s side with distribution links on the subscribers’ end. The rapid expansion of FTTH networks and the subsequent growth needed in operational team size engender more complex fiber distribution management, and that leads to an inevitable increase in human error. Moreover, manual ODFs are becoming prohibitively expensive, labor intensive systems, for which technicians will need to be dispatched for every service call or to roll out new links, as all connect/disconnect functions are done manually. Faced with growing operational expenses (OPEX) on top of the decline in the quality of their customer service, carriers are seeking new, cost-effective, flexible and modular solutions to manage fiber-networks reliably and efficiently, i.e., Automated ODF. 

Enhancing PON Topology Fiber Management

The continued evolution in IP-based services is driven by the growing demand for higher bandwidth and the steadily increasing number of users. Bandwidth hunger services, such as IPTV for HDTV / 3DTV and online gaming, currently require speeds of 50−100 Mbps, a figure that is growing exponentially as the numbers of users and of television sets per subscribed home rise. To keep pace with this growth, therefore, telecom networks must learn to better exploit their fiber optic infrastructures.

Operators who choose TeliSwitch’s AODF can implement AODF using PON topology in single-operator architectures or they can combine point-to-point topology with point-to-multipoint PON topology in multi-operator architectures.  Such flexibility allows the operator to mix differently sized AODF units, smoothly integrating small AODF units in manholes with larger units in street cabinets.

PON with typical AODF

In a typical deployment of AODF with PON, new subscribers can be connected to different PON splitters, saving on OLT cards as with AODF it requires an optical line terminal (OLT) that is only a partially populated.

Combining AODF in PON topology affords operators a much more in-depth view of their networks than what is possible using a manual ODF but at a similar cost. TeliSwitch’s AODF allows operators to monitor their physical layer, from beyond the embedded splitter and all the way to the subscriber’s splitters. In addition to end-to-end service provisioning and reduce human interventions and errors, using AODF enables remote testing and provides OLT port protection. Read more >>

PON with adaptive splitting ratios

In an advanced PON deployment, TeliSwitch promotes the adaptability of PONs to service penetration and bandwidth demand at no additional cost, offering its new PON-AODF – an automated optical distribution frame coupled with adaptive splitting capabilities. Read more >>

Manageable FTTH PON Topology

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  • Gradual OLT card population
  • Rapid service activation
  • OLT-to-ONT optical layer testing (bypassing the optical splitters)
  • Remote monitoring & maintenance
  • OLT marginal protection service (MPS)
  • Save on OPEX

AODF and PON-AODF enable PON Remote Testing

Operators that implement AODF in a PON topology also benefit by connecting their testing equipment (i.e., OTDR) directly to the AODF. Traditionally, a carrier that used typical testing equipment (i.e., OTDR) achieved only a partial view of fiber infrastructure as the carrier could only penetrate to the passive splitter unit. In this scenario, a technician must be dispatched for operational activities that occur between the passive splitter box and the users’ optical network termination (ONT) at the home and that require maintenance. However, connecting the TeliSwitch automated ODF (AODF) at the CO end to the operator’s testing equipment creates a temporary by-pass for testing the FO segment from the splitter box to the ONT unit, thus providing a holistic view of the optical network that enables immediate event analysis and remote fiber re-configuration. The results – reduced operational costs and rapid mean-time-to-repair (MTTR) – ultimately improve user satisfaction.

Moreover, using AODF architecture also facilitates putting equipment protection service (EPS) into practice. Implementing AODF in a PON topology enables some of the OLT ports to be used as backups. Thus, in the event that one OLT-activated port fails, a backup port is remotely (and automatically) connected to dramatically reduce typical OLT MTTR.

FTTH Multi-operator Open Architecture

In FTTH multi-operator architecture, each operator deploys and manages its own feeder cables only up to the concentration point. The fibers that run from there to the end-user’s home can be managed by a third entity—either one of the operators sharing the concentration point or a different party—as defined by the local regulator. Using a manual ODF in such a case would prevent sharing point operators from achieving a full view of their optical infrastructure.

In addition, unlike in a backbone network, optical fibers in an FTTH network undergo several connection changes during their lifetimes. Managing and controlling fibers in an FTTH, therefore, is much more complicated. The management of an FTTH multi-operator distribution unit is even more complex than managing a single operator distribution unit, as only the users’ fibers need to be maintained in the latter, while in a multi-operator, unit fiber distribution must be managed among the different sharing operators. As the number of operators sharing a concentration unit increases, the number of interconnections grows, and thus, operators must be prepared to dispatch their technicians to remote sites more frequently. Consequently, operators are faced with more frequent damage to equipment and mistakes in interconnections or inventory, and the increased number of entries by technicians and other individuals to sensitive sites raises important security issues. Acquiring the capability to remotely perform these interconnectivity changes, therefore, is critically important in maintaining an always-on FTTH network.

Designed specifically for multi-operator architecture, TeliSwitch’s automated optical distribution frame (AODF) enables an end-to-end view of the optical layer and allows operators to remotely control fiber interconnection changes, providing timely and secure physical layer fiber maintenance. TeliSwitch offers a cutting-edge solution with a robust feature set to support remote fiber distribution of highly populated concentration points or distributed fiber optic infrastructure topologies that simplify fiber distribution and that reduce the operational costs associated with fiber management and control.

FTTH Multi-Operator Fiber Concentration Point Topology

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  • End-to-End optical layer monitoring
  • Highly populated concentration point
  • Modular architecture  –  Enabling scalable growth
  • Always-on connectivity –  Connections are preserved during power-loss & maintenance
  • Rapid remote subscriber connect/disconnect
  • Timely and secure physical layer maintenance

FTTH Multi-Operator Distributed Fiber Topology

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  • End-to-end optical layer monitoring
  • Distributed fiber deployment
  • Simple maintenance – Reduced OPEX
  • Always-on connectivity –  Connections are Preserved during power-loss
  • Rapid remote subscriber connect/disconnect
  • Timely and secure physical layer maintenance

What you receive with the TeliSwitch AODF multi-operator family

  • Standard-based, outside plant access equipment
  • Physical dimensions do not change when the system is built for number of operators
  • Customized system configuration
  • Real-time holistic view of the FTTH network
  • Fast roll-out of new links
  • Fast mean-time-to-repair
  • Rapid, remote interconnections and network re-configuration
  • Connect/disconnect at the click of a mouse
  • Secure network
    • Prevents any on-line intervention by any shared operator at one's fibers
    • Reduces the need for technician access to concentration point premises