Abstract: The invention pertains to optical fiber transmission systems, and is particularly relevant to transmission of high volume of data and voice traffic among different locations. In particular, the improvement teaches the use of a single optical transport system for both metropolitan area transport and long haul transport of data and voice traffic.

Abstract: A low-cost configuration of, and at the same time to control the variable dispersion compensator at a high speed in a variable dispersion compensator for compensating the wavelength dependent accumulated dispersion resulting from the wavelength dependency of the transmission fiber and fixed dispersion compensator in a long-distance high-speed WDM transmission system. In order to achieve the object mentioned above, the wavelength dependent representative characteristic of the transmission fibers 4-1 . . . n, and the wavelength dependent representative characteristic of the DCFs 13-1 . . . n are recorded and maintained in advance in the dispersion control circuit 5-1 . . .

Abstract: The present invention discloses a method of mapping Optical Payload Unit (OPU) k (k=1, 2, 3 or any positive integer) Ethernet signals (E) into Optical Transport Network (OTN) frames for 10 Gigabit Ethernet (10 GbE) Local Area Network Physical Layer (LAN PHY), wherein OPUk Overhead (OH) is altered by the relocation of Justification Control (JC) bytes, from the standardized ITU-T G.709 locations, into the novel locations of rows 1-3 of column 15. This allows for rows 1-4 of column 16 to be available for any type of Justification Overhead (JOH), such as four Negative Justification Opportunity (NJO) byte locations. Four NJO byte locations, combined with four Positive Justification Opportunity (PJO) byte locations in rows 1-4 of column 17, provides for up to nine justification state choices to be determined by the JC bytes.

Abstract: The present invention relates to an optical access system for dual service network, which mainly comprises an optical modulation device which is used to receive on-off keying (OOK) signal from cable network and radio frequency (RF) signal from wireless network, the optical modulation device then modulates the OOK signal and the RF signal to an optical signal and send out an output optical signal. Lastly, the output optical signal is being delivered to an optical receiving device through an optical fiber transmission channel, and the optical receiving device can access the OOK signal and RF signal from the output optical signal. In addition, the present invention does not require remote nodes (receiver side) to use any optical filter to discern on-off keying signal from cable network and RF signal from wireless network. The present invention can also apply to the field of wavelength-division multiplexing system.

Abstract: The subject invention pertains to a method and apparatus for multiplexing in optical fiber communications. The subject invention relates to a method and apparatus for spatial domain modulation in optical wavelengths. In a specific embodiment, the subject invention relates to a spatial domain multiplexer (SDM) for use with an optical fiber. Preferably, the input channels coupled into the fiber optic cable include collimated laser beams. The techniques of the subject invention can be utilized with single mode and multi mode waveguide structures, for example, single mode and multi mode optical fibers. The subject invention is applicable to step index optical fiber and to graded index optical fiber. Applications of the subject technology can include secure data links, for example, which can modulate data such that if the data is intercepted, the data cannot be interpreted. The subject methods and apparatus can also be used in conjunction with other multiplexing techniques such as time-domain multiplexing.

Abstract: An arrangement includes a photonic band-gap assembly comprising at least one input wave guide and at least one output wave guides, and at least one routing element responsive to signals to selectively route a signal from the input wave guide to one or more of the output wave guides.

Abstract: A TDM PON including: an optical line terminal; a remote node including multiple secondary optical distributors connected to multiple optical network units; and the multiple optical network units generating and outputting a corresponding upstream optical signal. Each of the secondary optical distributors splits an upstream optical signal input from one of the optical network units connected thereto so as to generate split upstream optical signals and transmits one of the upstream optical signals to the optical line terminal, and transmits another upstream optical signal to a different optical network unit.

Abstract: Channel switching system and method of an IPTV service in a passive optical network (PON) are disclosed. To reduce a channel switching time of an IPTV system in the passive optical network, the system and the method use a channel switching control module and a channel list module in the passive optical network. In a case where a passive optical network system receives an IPTV channel switching request transmitted from a terminal user, the channel switching control module checks a recording of a channel list module and a recording of an authentication list module, and then updates a filter recording of an optical network unit to thereby directly transmit an image flow of a new channel in the passive optical network. When such system and method are applied to the passive optical network, high-speed switching of the IPTV service channel by the terminal user can be realized.

Abstract: The invention provides an optical device, including a light-transmissive substrate, and a pair of different, parallel gratings including a first grating and second grating, located on the substrate at a constant distance from each other, each of the pair of parallel gratings including at least one sequence of a plurality of parallel lines, wherein the spacings between the lines gradually increase from one edge of the grating up to a maximum distance between the lines, and wherein the arrangement of lines in the second grating is in the same direction as that of the first grating. A system utilizing a plurality of such optical devices is also disclosed.

Abstract: A digital optical network (DON) is a new approach to low-cost, more compact optical transmitter modules and optical receiver modules for deployment in optical transport networks (OTNs). One important aspect of a digital optical network is the incorporation in these modules of transmitter photonic integrated circuit (TxPIC) chips and receiver photonic integrated circuit (TxPIC) chips in lieu of discrete modulated sources and detector sources with discrete multiplexers or demultiplexers.

Abstract: Address setting and initial data setting of an oil-resistant, water-resistant control/monitor terminal for performing address setting and initial setting of control/monitor terminals of a transmission control system in an oil-mist or humid environment. Also provided is optical communications or electromagnetic induction through a light transmission window provided in the control/monitor terminal using a data-setting-circuit-equipped console.

Abstract: The present invention is directed to a Fiber Selective Control Switch system for simulating human intervention during a test process for fiber network environments. The Fiber Selective Control Switch system may comprise a MCU, and at least one FSCS module mounted on a SFP device. The MCU is download programmable with basic code, which remotely controls FSCS modules. Each FSCS module coupled to the MCU may include two MOSFETs and a pull down resistor. A positive signal voltage from the MCU to the FSCS module mounted on SFP device will disconnect the fiber connection. A low signal voltage from the MCU to the FSCS module will re-connect the fiber connection. Advantageously, the FSCS system may not affect normal fiber operations due to fast switching characteristics of MOSFET devices and the MCU's low power requirement.

Abstract: In an optical transmission apparatus, optical power of each of wavelength contained in a wavelength multiplexing signal is measured, a measured value of the optical power of each wavelength is compared with a predetermined threshold value, a total value of the measured values of the optical power, which are equal to or larger than the threshold value, is calculated as a total value of signal beam power, and a total value of the measured values of the optical power, which are less then the threshold value, is calculated as a total value of ASE power. The number of the measured values of the optical power, which are equal to or larger than the threshold value, is calculated as a wavelength count of the signal beams contained in the wavelength multiplexing signal. A signal-to-ASE ratio is calculated from the total value of the signal beam power and the total value of the ASE power.

Abstract: Consistent with the present disclosure, an arrayed waveguide grating (AWG) is provided that includes first inputs and second inputs. Each of the first inputs receives a corresponding one of a plurality of first optical signals, each of which has a corresponding one of a plurality of wavelengths. Second inputs are also provided, such that each second input is preferably provided between two adjacent first inputs. Each of the second inputs receives a corresponding one of a plurality of second optical signals, and each of the second plurality of optical signals has a corresponding one of those wavelengths. Each of the first plurality of optical signals, however, has a first polarization and each of the second plurality of optical signals has a second polarization different than the first polarization.

Abstract: In a system where a quantum channel and a classical channel are multiplexed on a single optical transmission line and information is transmitted from a transmitter to a receiver through the quantum channel, the classical channel is inhibited from affecting the quantum channel. To this end, the transmission characteristics of a transmitter-side wavelength multiplexer/demultiplexer for the classical channel, the transmission characteristics of a receiver-side wavelength multiplexer/demultiplexer for the quantum channel, and the optical power of a light source for the classical channel are designed so that crosstalk light due to spontaneous emission light and crosstalk light due to nonlinear optical effects can be suppressed, and the classical channel does not affect the quantum channel.

Abstract: Provided are a sing-unit integrated transceiver having a pump source and a transceiver module using the transceiver.

Abstract: A passive optical network is provided, which includes an optical central office connected to a line termination device by a branch of the network including a passive amplification medium. The central office is adapted to send/receive a first data optical signal and has a first amplifier for sending a second amplification optical signal. The second signal exciting the amplification medium to amplify the optical power of an optical signal. The line termination device is adapted to receive the first optical signal, modulate the second amplification optical signal; and inject the modulated second signal into the network.

Abstract: A network connection device for performing a process of transmitting and receiving a SONET/SDH frame includes a first protocol processor which processes a first network management protocol; a second protocol processor which processes a second network management protocol; a frame header extractor which extracts a header from the received SONET/SDH frame; and a protocol identifier which identifies a network management protocol based on the extracted frame header. The network connection device selects one of a control signal outputted from the first protocol processor and a control signal outputted from the second protocol processor based on a result of the identification, and outputs the control signal.

Abstract: In a passive optical network system, in order that by measuring a transmission distance and a transmission time between an OLT and an ONU in operation of the system, if the distance or the time is short, communication is conducted at a high transmission speed to increase a capacity of user; if the distance or the time is long, communication is conducted at a low transmission speed to increase the capacity of user communicating in a state in which a predetermined quality is secured, a main station includes a signal communication circuit to communicate with subsidiary stations at a first or second transmission speed and a controller to measure a transmission distance or a transmission time between the main station and each subsidiary station. Based on a result of the measurement, the controller selects a transmission speed for communication with the subsidiary station.

Abstract: An optical signal division transmission system in which an input optical signal is divided into N parts (termed as “N-part optical signals”) and transmitted at a transmission rate of 1/N, wherein an additional optical wave path is provided separately from an optical wave paths for transmitting said N-part optical signals, and even if a malfunction occurs in any one of said optical wave paths for transmitting said N-part optical signals, transmission of said N-part optical signals is continued, using said additional optical wave path.

Abstract: This invention provides an optical communication apparatus in which the nonlinear degradation of a wavelength multiplexed signal in the nonlinear degradation factor member causing the nonlinear degradation is reduced, an optical transmission system using the same, and a method for reducing the nonlinear degradation. There are provided a wavelength interval enlarging portion 51 for enlarging a wavelength interval of an inputted wavelength multiplexed signal, a nonlinear degradation incidental processing portion 52 for applying arbitrary processing involving the nonlinear degradation to the wavelength multiplexed signal whose wavelength interval is enlarged, and a wavelength interval recovering portion 53 for recovering the wavelength interval of the wavelength multiplexed signal to which the arbitrary processing is applied to the original wavelength interval.

Abstract: An optical line terminal connecting with numbers of optical network units comprises a control unit which controls each optical network unit to make it operate in a first mode in which transmission and reception of control messages and data are possible or in a second mode in which the transmission and reception of control messages are possible but the transmission of data is impossible, according to a communication permission request transmitted from an optical network unit and based on a preset maximum number of optical network units permitted to execute upstream communication from the optical network unit to the optical line terminal.

Abstract: An optical network having a tree-like structure with a main line and a plurality of branches, at least two of the branches comprising a monitoring unit for upstream signalling to the main line, wherein each of the monitoring units comprises a signal generation unit with a light source for generation of a pre-defined optical signal, and the monitoring units are construed to generate pre-defined optical signals which are different from each other, as well as a monitoring unit for generating a periodic upstream signal in such an optical network and a method for monitoring such an optical network.

Abstract: In general, in one aspect, the disclosure describes a multi-stage switch having at least one ingress switch module to receive data and to generate frames that are transmitted as a wavelength division multiplexed signal. The multi-stage switch further includes a core switch module operatively connected to receive the wavelength division multiplexed signal from the at least one ingress switch module and to switch the frames. The multi-stage switch additionally includes at least one egress switch module to receive the wavelength division multiplexed signal from the core switch module and to transmit data.

Abstract: A computerized method for modifying an optical wavelength division multiplexing (WDM) network is described. The method includes providing an initial configuration of the optical WDM network. At least one parameter that represents a characteristic of a span in the optical WDM network as defined by the initial configuration is evaluated. The initial configuration of the optical WDM network is modified in response to the evaluation. The method can also include determining if a predetermined set of engineering rules are satisfied.

Abstract: Systems and method of compensating for transmission impairment are disclosed. One such method comprises: receiving an optical signal which has been distorted in the physical domain by an optical transmission channel; and propagating the distorted optical signal backward in the electronic domain in a corresponding virtual optical transmission channel.

Abstract: An exemplary object of the present invention is to accurately reflect allocation requests and increase the bandwidth use efficiency without requiring expensive and fast integrated circuits or CPUs in the control unit even in a large-scale system with a large number of terminal devices. A subscriber station comprises allocating means for determining bandwidth allocation based on a predetermined allocation condition and bandwidth transmitting means for transmitting bandwidth allocation information determined by the allocating means to an optical line terminator. The optical line terminator comprises pipeline transmitting means for transmitting bandwidth allocation information transmitted from the subscriber stations to all subscriber stations to be allocated with bandwidth.

Abstract: A non-sampling-based Q-factor measuring apparatus and method use a power conversion module to transform the power variation of inputted optical signals in time domain into the variation in other domains, such as optical wavelength, optical polarization and different output ports of optical elements. Taking optical wavelength as an example, different levels of power variation respond different outputs of wavelength variation through the use of a power-to-wavelength conversion module. An optical filter then separates the inputted optical signals with different wavelengths. The power average of a wavelength for its corresponding optical signals is further calculated by a photo detector. Thereby, the information of the power variation for the inputted optical signals at levels 1 and 0 can be obtained, and the Q-factor for the inputted optical signals is easily measured.

Abstract: A communications system includes a physical layer device (PLD) and a logical link device (LLD), each having respective send and receive interfaces being substantially identical to define symmetrical interfaces for the system. Accordingly, design and manufacturing is simplified compared to conventional systems. In addition, advantages are also provided in terms of loopback capability and packaging options. The PLD comprises a PLD send interface including PLD parallel information outputs, and a PLD receive interface including PLD parallel information inputs. Similarly, the LLD comprises an LLD receive interface including LLD parallel information inputs, and an LLD send interface including LLD parallel information outputs. Parallel communications channels connect the PLD information outputs to respective LLD information inputs, and connect the LLD information outputs to respective PLD information inputs.

Abstract: The present invention provides an apparatus and system for transmitting fiber channel services. The apparatus includes an FC service transmission module, a mapping module, a label adding module, an FC service receiving module, a label removing module, and a demapping module. In the embodiments of the present invention, transport channel labels are added for FC services, and FC services are multiplexed into a packet physical interface. Thus, FC services can be transmitted in the packet switched network transparently. Besides, FC services are loaded into the Ethernet payload so that there is no need to generate a GFP idle frame to adapt to the Ethernet payload, thus simplifying the process.

Abstract: An optical multiplexer/demultiplexer comprises one light guide main line which guides lights of a plurality of wavelengths, and two or more microring optical resonators directly optically coupled to the one light guide main line. The two or more microring optical resonators are arranged in any two of layers higher than, level with, and lower than a plane where the one light guide main line is disposed, and/or the two or more microring optical resonators are arranged on both sides of the one light guide main line in a light guide direction.

Abstract: A ring connection system and method are providing for distributing signals in an optical-to-electrical interface. The method electrically connects a plurality of nodes in a series-connecting ring, and receives an optical signal at a first node from a service provider. The method converts the optical signal to an electrical signal, and distributes the electrical signal via the ring. At each node, the electrical signal is supplied from a customer interface. Typically, each node has a plurality of customer interfaces. In one aspect, ITU-T G.984.3 Giagbit-capable Passive Optical Network (GPON) optical signals are received converted to a customer interface electrical signal such as an Ethernet connecting transfer mode, or time division multiplexed signal. Electrically connecting the plurality of nodes in the series-connected ring includes: series connecting the nodes in a North ring; and, series connecting the nodes in a South ring, opposite in direction from the North ring.

Abstract: The present invention provides frame-interleaving systems and methods for Optical Transport Unit K (OTUK) (i.e. Optical Transport Unit 4 (OTU4)), 100 Gb/s Ethernet (100 GbE), and other 100 Gb/s (100 G) optical transport enabling multi-level optical transmission. The frame-interleaving systems and methods of the present invention support the multiplexing of sub-rate clients, such as 10×10 Gb/s (10 G) clients, 2×40 Gb/s (40 G) plus 2×10 G clients, etc., into two 50 Gb/s (50 G) transport signals, four 25 Gb/s (25 G) transport signals, etc. that are forward error correction (FEC) encoded and carried on a single wavelength to provide useful, efficient, and cost-effective 100 G optical transport solutions today. In one exemplary configuration, a 100 G client signal or 100 G aggregate client signal carried over two or more channels is frame-deinterleaved, followed by even/odd sub-channel FEC encoding and framing.

Abstract: The invention relates to a network comprising at least one host device having an interface card connected to a backplane of said host device, wherein said interface card comprises at least one cage for receiving a pluggable module which performs a traffic management of data transported via at least one optical fibre connected to said pluggable module.

Abstract: An Ethernet service configuration device, method, and system in a passive optical network (PON) are provided. The device includes a PON protocol processing module, an Ethernet module, and at least one service module based on Ethernet which are sequentially connected. The Ethernet module includes a media access control (MAC) bridge port configuration data management entity (ME) and an Ethernet service end node ME connected with each other. The service module based on Ethernet includes at least one non-Ethernet service functional end node ME correlated with the Ethernet service end node ME. According to the device, method, and system, the coupling between Ethernet service configuration and all kinds of service and/or device configurations based on Ethernet is reduced, which is propitious to the ONT maintenance and modularization configuration.

Abstract: A light beam which is used for transmitting a wavelength division multiplex signal is guided to a Bragg grating via an adjustable mirror. According to the angle of incidence of the light beam relative to the longitudinal axis of the Bragg grating, different transmission characteristic curves having different gradients are produced. As a result thereof, scattering of the wavelength division multiplex signal can be compensated. A second controllable mirror enables the damping to be adjusted. A control device effects a rapid correction of the scattering after data signals are connected or disconnected.

Abstract: A network comprising at least one host device having an interface card connected to a backplane of said host device, wherein said interface card comprises at least one cage for receiving a pluggable module which provides at least one embedded communication channel which exchanges performance monitoring data and configuration data between said pluggable module and a far end device.

Abstract: An optical diplexer module includes: an optical diplexer module comprising: a multiplexing unit multiplexing RF signals and a wideband digital signal having a baseband bandwidth to output a single multiplexed signal; an E-O converter converting the multiplexed signal into an optical signal and externally outputting the optical signal; and an O-E converter converting an externally received optical signal into an electric signal and outputting the electric signal. Similarly to existing optical transceivers, the optical diplexer module can provide TPS and MPS services using only two optical wavelengths for upstream and downstream signals. Since no separate optical wavelength is additionally required, the optical diplexer module can allows the numbers of components and processes to be reduced. It may result in yield improvement and cost reduction. Also, since electric or optical crosstalk between modules can be reduced, its performance can be improved.

Abstract: A high-capacity digital communications system and method of transporting 10 GbE LAN packets between user devices over an OTN network that allows the packets to be transported in a manner that is transparent to the destination device(s) on the network. The digital communications system includes an OTN network, and at least one source device and at least one destination device connected to the network via respective 10Gbase-R interfaces. The system transports 10 GbE LAN data packets over the OTN network by performing decoding on the packets to recover the preamble and variable length data contained in each packet, removing the IPG between successive packets in the stream, encapsulating the packets including the respective preambles and data, and mapping the encapsulated packets to the overhead and payload areas of ODUk frames. The packets are then transported over the OTN network from the source device to the destination device.

Abstract: A reduced size multiplexer and, in particular, a reduced size SONET multiplexer module is provided for use in a reduced size enclosure. The SONET multiplexer module has electrical and optical connectors on its faceplate to provide ease in access without having to remove the SONET multiplexer from the enclosure. The SONET multiplexer circuit is configured in a standard Type 400 mechanics circuit board arrangement. The SONET multiplexer module therefore can be inserted into an enclosure in a direction opposite to that in which the DS1 or DS3 connector projects from the face plate, so that the DS1 or DS3 connector remains freely accessible outside of the enclosure when the SONET multiplexer module is fully loaded into the enclosure. DS1 and DS3 cables and optical fibers can thus be easily coupled to the DS1 and DS3 and optical connectors, respectively, when the SONET multiplexer circuit is fully loaded into the enclosure.

Abstract: An optical module comprising: a submount provided on a CAN stem; light-emitting device and a light-receiving device; a CAN cap or package; and an optical multiplexer/demultiplexer having a wavelength selective filter on a substrate that has transmissivity to passing light and a mirror, where an extending direction of the optical multiplexer/demultiplexer is fixed in the CAN cap or the package being tilted by an angle ? (??2N?, N=0, 1, 2, . . . ) in a two-dimensional cross section with respect to one surface of an optical device mounting board, outgoing light from the light-emitting device passes through the wavelength selective filter and the substrate and enters an optical fiber outside the cap, and outgoing light from the optical fiber enters the optical multiplexer/demultiplexer and is reflected by the wavelength selective filter and further reflected by the mirror, and then exits the optical multiplexer/demultiplexer to enter the light-receiving device.

Abstract: A variety of adaptable electronic duobinary generating filters to be used in communication systems are provided, each filter generating an adaptable electronic duobinay signal which is optimized for system impairments. According to one exemplary implementation, an adaptable electronic duobinary generating filter comprises an adaptable delay-and-add circuit, having an adaptable electronic delay element having a delay ?T: 1/T being the bit rate of the binary data input into the adaptable delay-and-add circuit, and a being an adaptation parameter which can be optimized depending on the system impairments. In one optional implementation, the adaptable electronic delay element can be programmably adaptable to optimize against deterministic system impairments. In another optional implementation, the adaptable electronic delay element can be dynamically adaptable to optimize against dynamically varying system impairments.

Abstract: One embodiment provides an ONU that includes an optical interface coupled to an optical transceiver, which is configured to transmit optical signals to and receive optical signals from an OLT through the optical interface. The ONU also includes an ONU chip coupled to the optical transceiver and configured to communicate with the OLT through the optical transceiver. The ONU further includes an Ethernet interface coupled to the ONU chip and a power management module configured to provide power to the ONU chip and the optical transceiver using power delivered from a CPE through the Ethernet interface. In addition, the ONU includes a circuit board to which the optical transceiver, the ONU chip, and the power management module are attached, and a wall-mountable fixture, wherein the front side of the fixture includes an opening for the Ethernet interface, and wherein the back side of the fixture holds the circuit board.

Abstract: A communication system includes a multiplexer configured to multiplex a first set of data channels into a first data channel and to multiplex a second set of data channels into a second data channel, and a delay adjuster configured to adjustably delay the first data channel based on a delay adjust command. The communication system also includes a first amplifier configured to amplify the delayed first channel into a first output data channel, and a second amplifier configured to amplify the second data channel into a second output data channel. The communication system further includes a first driver configured to convert the first output data channel into a first drive signal to drive an optical modulator, and a second driver configured to convert the second output data channel into a second drive signal to drive the optical modulator.

Abstract: From an real valued OFDM signal (S0(t)) is a baseband signal (SB(t)) derived and converted into a complex single sideband modulation signal (n(t)). This is modulated onto an optical carrier (fOC) to generate a SSB transmission signal (SOT) having a small bandwidth an carrying the information in the envelope or in the power of the envelope. According to the modulation direct detection is possible. Only a small bandwidth is necessary for the transmission.

Abstract: Apparatus, systems and techniques that use a single laser to generate desired optical WDM comb frequencies.

Abstract: A storage device includes a memory that stores data, a memory controller that controls reading and writing of data from and to the memory, and a host controller. The host controller transmits and receives the data to and from a host via a transmission line. The host controller transmits and receives the data, via an optical transmission line, to and from (i) the memory controller and (ii) a memory controller of at least one other storage device.

Abstract: A method for assigning a light-trail in an optical network includes identifying unassigned traffic flows in the network that require assignment to a light-trail, where each traffic flow is communicated from an associated source node to an associated destination node. The method also includes identifying which unassigned traffic flow includes the largest amount of traffic, establishing a new light-trail beginning at the source node of the identified traffic flow and ending at the destination node of the identified traffic flow, and assigning the identified traffic flow to the established light-trail. Furthermore, the method includes determining whether there are any unassigned traffic flows having associated source and destination nodes included in the established light-trail.

Abstract: In a PON system in which communication is performed at a plurality of types of transmission rate (L, M, and H) in an upstream direction from a plurality of terminals connected to a station apparatus through optical fibers, within a discovery period for allowing an unregistered terminal to be recognized by station apparatus, the terminal makes a discovery response at one type of transmission rate (L). With this configuration, station apparatus can wait for a discovery response with a receive function being allowed to support transmission rate (L).

Abstract: A multi-access network terminal includes first and second communication interfaces. The first interface is configured to communicate with a first service provider providing services to a user through the first interface with a first type of signal and/or a first type of communications protocol. The second interface is configured to communicate with the first service provider providing services to the user through the second communication interface using a second type of signal and/or a second type of communications protocol. Alternatively, the second interface is configured to communicate with a second service provider providing services to the user through the second communication interface using the first or second type of signal and/or the first or second different type of communications protocol.