Category: Fiber Transceivers

Optical transceivers, Active Optic Cables, data center switches, and cable management in data centers.

Common Types Of Fiber Optic Cables And Patch Cables

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1.FTTH Fiber Optic Cable

FTTH (Fiber To The Home), as its name suggests it is a fiber optic directly to the home. Specifically, FTTH refers to the optical network unit (ONU) mounted on home users or business users, is the optical access network application type of closest to users in optical access series except FTTD(fiber to the desktop).

There are 5 main advantages of FTTH:

First, it is a passive network, from the end to the user, the intermediate can be basically passive;

Second, the bandwidth is relatively wide, long distance fits the massive use of operators;

Third, because it is carried business in the fiber, and there is no problem;

Fourth, because of its relatively wide bandwidth, supported protocol is more flexible;

Fifth, with the development of technology, including point-to-point, 1.25G and FTTH have established relatively perfect function

2. Indoor Fiber Optic Cable

Indoor optical cable is classified according to the using environment, as opposed to outdoor fiber optic cable.

Indoor optical cable is a cable composed of fiber optic (optical transmission medium) after a certain process. Mainly by the optical fiber (glass fiber is as thin as hair),plastic protective tube and plastic sheath. There is no gold, silver, copper and aluminum and other metal, fiber optic cable generally has no recycling value.

Indoor fiber optic cable is a certain amount of fiber optic forming to cable core according to a certain way, outsourcing jacket, and some also coated layer of protection, to achieve a communication line of light signal transmission.

Indoor cable is small tensile strength, poor protective layer, but also more convenient and cheaper. Indoor cable mainly used in building wiring, and connections between network devices.

3. Outdoor Fiber Optic Cable

Outdoor fiber optic cable, used for outdoor environment, the opposite of indoor cable.

Outdoor cable is a type of communication line to achieve light signal transmission, is composed of a certain amount of fiber optic forming to cable core according to a certain way, outsourcing jacket, and some also coated with outer protective layer.

 

Outdoor cable is mainly consists of optical fiber (glass fiber is as thin as hair), plastic protection tube and plastic sheath. There is no gold, silver, copper and aluminum and other metal cable, generally no recycling value.

Outdoor cable is greater tensile strength, thick protective layer, and usually armored(wrapped in metal). Outdoor cables are mainly applied to buildings, and remote networks interconnection.

4.Fiber Optic Patch Cable

Fiber optic patch cable, also known as fiber jumper, used to connect from the device to fiber optic cabling link. Fiber jumper has a thick protective layer, generally used in the connection between the fiber converter and Fiber Termination Box. Commonly used fiber jumpers include: ST, LC, FC and SC.

Main Categories

Single-mode fiber patch cable: General single-mode fiber jumper is colored in yellow, connector and protective sleeve are blue; long transmission distance.

Multi-mode fiber patch cable: General multimode fiber jumper is colored in orange and some in gray, connector and protective sleeve are beige or black and the transmission distance is short.

Typical Outdoor Fiber Optic Cables

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Fiber optic cable provides protection for the fibers from the environment encountered in an installation. Outdoor Fiber Cable is designed strong to protect the fibers to operate safely in complicated outdoor environment, it can be buried directly, pulled in conduit, strung aerially or even placed underwater. While indoor cables don’t have to be that strong.
Outdoor fiber optic cable is composed of many fibers enclosed in protective coverings and strength members. Common features for fiber optic cable include polarization maintaining, graded index, and metalization. Most outdoor fiber cables are loose buffer design, with the strengthen member in the middle of the whole cable, the loose tubes surround the central strength member. Inside the loose tube there is waterproof gel filled, whole cable materials used and gels inside cable between the different components will help make the whole cable resist of water.
Typical outdoor fiber optic cable types are used for aerial, direct buried and duct applications.
Loose Tube Cables
Loose Tube cables are the most widely used cables for outside plant trunks, as it can be made with the loose tubes filled with gel or water absorbent powder to prevent harm to the fibers from water. Loose Tube Fiber Optic cables are composed of several fibers together inside a small plastic tube, which are in turn wound around a central strength member and jacketed, providing a small, high fiber count cable. They can be installed in ducts, direct buried and aerial/lashed installations for trunk and fiber to the premise applications. Loose tube cables with singlemode fibers are generally terminated by spicing pigtails onto the fibers and protecting them in a splice closure. Multimode loose tube cables can be terminated directly by installing a breakout kit, also called a furcation or fan-out kit, which sleeves each fiber for protection.
Ribbon Cable
Ribbon cable is preferred where high fiber counts and small diameter cables are needed. This cable has the highest packing density, since all the fibers are laid out in rows in ribbons, typically of 12 fibers, and the ribbons are laid on top of each other. Not only is this the smallest cable for the most number of fibers, it’s usually the lowest cost. Typically 144 fibers in ribbons only has a cross section of about 1/4 inch or 6 mm and the jacket is only 13 mm or 1/2 inch diameter! Some cable designs use a “slotted core” with up to 6 of these 144 fiber ribbon assemblies for 864 fibers in one cable! Since it’s outside plant cable, it’s gel-filled for water blocking or dry water-blocked. These cables are common in LAN backbones and data centers.
Armored Fiber Optic Cable
Armored cable is used in direct buried outside plant applications where a rugged cable is needed and/or for rodent resistance. Armored cable withstands crush loads well, for example in rocky soil, often necessary for direct burial applications. Cable installed by direct burial in areas where rodents are a problem usually have metal armoring between two jackets to prevent rodent penetration. Another application for armored fiber optic cable is in data centers, where cables are installed under the floor and one worries about the fiber cable being crushed. This means the cable is conductive, so it must be grounded properly.
A Pair of 10/100M Single Fiber 1-port SC/ST/FC & 1-port RJ45 BIDI WDM Fiber Media Converter
Aerial Fiber Optic Cable
Aerial cables are for outside installation on poles. They can be lashed to a messenger or another cable (common in CATV) or have metal or aramid strength members to make them self supporting. A widely used Aerial Cable is optical power ground wire (OPGW) which is a high voltage distribution cable with fiber in the center. The fiber is not affected by the electrical fields and the utility installing it gets fibers for grid management and communications. This cable is usually installed on the top of high voltage towers but brought to ground level for splicing or termination.
Indoor/Outdoor Cables
Fiber Optic Indoor/Outdoor Cables are designed to meet both the stringent environmental requirements typical of outside plant cable AND the flammability requirements of premise applications. Ideal for applications that span indoor and outdoor environments. By eliminating the need for outside to inside cross-connection, the entire system reliability is improved and with lower overall installation costs.
Underwater and Submarine Cables
It is often necessary to install fibers under water, such as crossing a river or lake where a bridge other above water location is not possible. For simple applications a rugged direct burial cable may be adequate. For true undersea applications, cables are extremely rugged, with fibers in the middle of the cable inside stainless steel tubes and the outside coated with many layers of steel strength members and conductors for powering repeaters. Submarine cables are completed on shore, then loaded on ships and laid from the ship, often while operational to ensure proper operation.
FiberStore offers a comprehensive range of multimode fiber cable and single-mode fiber optic cables. Indoor, outdoor, armoured, tight buffered or loose tube structures, which cover all possible applications.

Fiber Optic Cable are usually used in two scenarios

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Fiber Optic Cable are used in applications where the optical signal is too strong and needs to be reduced. For example, in a multi-wavelength fiber optic system, you need to equalize the optical channel strength so that all the channels have similar power levels. This means to reduce stronger channels’ powers to match lower power channels.
The attenuation level is fixed at 5 dB, which means it reduces the optical power by 5dB. This attenuator has a short piece of fiber with metal ion doping that provides the specified attenuation.
There are many different mechanisms to reduce the optical power, this picture shows another mechanism used in one type of variable attenuator. Here variable means the attenuation level can be adjusted, for example, it could be from 1 dB up to 20dB.

Fiber Optic Cable are usually used in two scenarios.
The first case is in fiber optic power level testing. Cable are used to temporarily add a calibrated amount of signal loss in order to test the power level margins in a fiber optic communication system.
In the second case, Cable are permanently installed in a fiber optic communication link to properly match transmitter and receiver optical signal levels.
Optical Cable are typically classified as fixed or variable Cable.
Fixed Cable have a fixed optical power reduction number, such as 1dB, 5dB, 10dB, etc.
Variable Cable’ attenuation level can be adjusted, such as from 0.5 dB to 20dB, or even 50dB. Some variable Cable have very fine resolution, such as 0.1dB, or even 0.01dB.
This slide shows many different optical attenuator designs.
The female to female fixed Cable work like a regular adapter. But instead of minimizing insertion loss, it purposely adds some attenuation.
The female to female variable Cable are adjustable by turning a nut in the middle. The nut adjusts the air gap in the middle to achieve different attenuation levels.
The male to female fixed Cable work as fiber connectors, you can just plug in your existing fiber connector to its female side.
The in-line patch cable type variable Cable work as regular patch cables, but your can adjust its attenuation level by turning the screw.
For precise testing purposes, engineers have also designed instrument type variable Cable. These instrument type Cable have high attenuation ranges, such as from 0.5 dB to 70dB. They also have very fine resolution, such as 0.01dB. This is critical for accurate testing.

Security mechanisms in FOT PON solutions

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 Designed with carrier-class reliability, the FOT GEPON/GPON solution can fully guarantee the security of subscribers’ services.
Supports L2 to L7 packet filtering function.
Performs the illegal frame filtering based on source MAC address, destination MAC address, source IP address, destination IP address, port No., Ethernet type, protocol type, VLAN and VLAN range, so as to prevent illegal attempts to access the Internet.
Supports protection against DOS attack to enhance the anti-attack capability.
Supports ACL (Access Control List)-based permission / denial controls.
Supports protection against ICMP (Internet Control Message Protocol) / IP message attack.
Supports protection against ARP (Address Resolution Protocol) attack.
Supports the user operation authority management.
Both GUI and CLI network management systems can provide operator accounts with different operating rights, so as to ensure operating security of the network management system.
Supports automatic reporting of ONU SN and MAC address to the network management system.
Supports authenticating ONU based on multiple modes.
The authenticating ONU can be based on physical address, logic identifier, logic identifier+password, logic identifier+physical address, logic identifier +password+physical address.
Supports broadcast storm control.
Supports frame filtering and rate limiting.
Supports access security control through DHCP Option-82 and PPPOE+.
The FOT GEPON/GPON solution can insert physical information into protocol messages of DHCP request dial or PPPoE dial. When used in combination with a verifying system, it can effectively and dynamically control subscriber access to specific network resources, so as to greatly facilitate troubleshooting and attack positioning.
Supports the DHCP snooping function.
The ONU snoops subscriber information such as MAC address, IP address, lease time and VLAN ID, so as to trace and locate DHCP subscriber’s IP address and port by establishing and maintaining a DHCP snooping binding table. In addition, it directly discards illegal messages (ARP spoofing messages and the messages that modify IP address randomly). These illegal messages are not compliant with the binding table entries. Therefore, it guarantees DHCP environment integrity and consistency.
Supports limit on the maximum number of MAC addresses learned, to prevent MAC attack.
Supports limit on the number of MAC addresses that access a single FE interface of an ONU.
Supports limit on the number of multicast groups that a single FE interface of an ONU can join.
Supports the ONU port binding function.
Achieves the dynamic binding of FE interface and MAC address, so as to guarantee validity of subscribers accessing the network.
Supports AES-128 encryption and decryption algorithm to guarantee the security of subscribers’ data.

FTTH PON evolution: GPON to NG-PON2

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Evolution Path: GPON to NG-PON2
 After GPON Recommendations were done, FSAN and ITU-T continued the study of NG-PONs and defined the first phase of NG-PONs as systems that offer low costs, large capacity, wide coverage, full service, and interoperability with existing technology. FSAN and ITU-T members also agree that long term PON evolution will be driven by new scenarios if coexistence with legacy systems is not required. In addition to time-division multiplexing (TDM) PONs, other technologies for NG-PON could also be taken into account.
 The key to a successful upgrade is to make sure that no changes are required to the optical distribution network. This requires the operator to place a coexistence element (CE) in the central office, and to make sure the current GPON ONTs/ONUs are equipped with the WDM filters as described in ITU-T G.984.5.
  The evolution to a NG-PON2 network can be performed by inserting a NG-PON2 blade at the optical line terminal (OLT) and routing the fibres to the coexistence element (CE). Figure following: Coexistence of GPON and NG-PON2
What is NG-PON2
  NG-PON2 (Next-Generation Passive Optical Network 2) is a 2015 telecommunications network standard for a passive optical network (PON). The standard was developed by ITU and details an architecture capable of total network throughout of 40 Gbps, corresponding to up to 10 Gbps symmetric upstream/downstream speeds available at each subscriber.
  A passive optical network is a last mile, fibre-to-the-x telecommunications network that broadcasts data through fibre optic cables. PONs are managed by passive optics such as unpowered splitters and filters, offering high reliability and low cost compared to active networks. The PON data stream is generally converted to a more traditional service such as Ethernet and Wi-Fi at the subscriber’s location.
  NG-PON2 is compatible with existing PON fibre by replacing optical line terminal (OLT) at the central office, and the optical network unit (ONU) near each end-user.

What features are most wanted in a PON ONT terminal?

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  “Can you please check your ont compliance?” “Please check the ONT Specification in attached file.” Usually, some of our global customers will bring a lot of questions regarding to the list of features in their PON ONT equipment requirement. Based on actual sales experience, our team is sharing a list of features, which are most wanted in a PON ONT terminal project.
Overview
  ONT should be Equipped with ITU-T G.984 compliant 2.5G Downstream and 1.25G Upstream GPON interface, supports the full Triple Play of services including voice, video, and high speed internet access service. Compliant with standard OMCI definition, ONT should be manageable at remote side and supports the full range FCAPS functions including supervision, monitoring and maintenance. ONT should also support TR069 management protocol.
data
The GPON ONT is delivered with four 10/100/1000 Base-T Ethernet data interfaces, supporting:
Auto-negotiation and MDI/MDIX auto-sensing.
Built-in layer-2 switch
Advanced data features such as VLAN tag manipulation, classification, and filtering
802.11 b/g/n/ac WLAN interface (Bridge mode Wifi)
Dual Band Wi-Fi (2.4GHz & 5GHz)
High Gain MIMO Antenna
Multiple Wi-Fi SSID (up to 4) – Each mapped to different LAN Port/ GEM Port
USB 2.0/3.0 storage
Voice
The ONT is delivered with up to two POTS interface ports for carrier-class voice services, supporting:
5 REN per line, balanced Ring at 55V RMS, DTMF dialing
Multiple voice codec
Supporting Echo Cancelling, VAD, CNG
Supporting static or dynamic jitter buffer
Various CLASS services – Caller ID, Call Waiting, Call Forwarding, Call Transfer, etc.
SIP (RFC3261)
Support multiple country-profiles
Video
The ONT should support video contents delivered in the form of data (by multicast or unicast).
In case where multicast technology is used for delivering video contents through data channel, the ONT supports the dedicated multicast GEM port on the Downstream. So the video contents are received and processed by all the ONTs through the unified channel and this greatly improves the bandwidth efficiency.
  In addition, the ONT supports IGMP snooping function to be applied for further optimization. When IGMP snooping is enabled, the ONT monitors the member joining and leaving activities at the Ethernet service port, and then selectively delivers the multicast streams.
Additional Features
ONT Battery Back-up Unit (OPTIONAL)
Full TR-069 Support for remote ONT Management
Web Configuration Interface
CLI Configuration Interface