VSATPlus II

The VSATPlus II provides a full mesh, hubless network with no single point of failure and offers the greatest ease of network configuration and expansion. It supports the most demanding network applications including high quality voice, low and high-speed data, video conferencing and fax - all in a single low-cost, integrated platform. Combined with the unique direct E1 telephony and Frame Relay interface, the VSATPlus II is the most cost-effective satellite communications solution for multi-line and/or multi-application networks in the world.

The VSATPlus II satellite communications terminal offers multiservice capability, using Time Division Multiple Access (TDMA) with Frequency Hopping (FHOP) technology. The system offers hubless, full mesh network connectivity with features that provide better price/performance levels.

Highlights:

• Voice, data, video and facsimile services combined in a single, low-cost platform
• Hubless, full mesh Demand Assigned Multiple Access (DAMA) operation with single satellite hop
• Maximum use of satellite bandwidth by combining TDMA and FHOP technology
• Fractional, split, DAMA E1 and DAMA Frame Relay
• PolarSat's StreamView™ Network Management System offers sophisticated network control for dynamic "Bandwidth on Demand" services
• Easily installed and expandable terminals for low-cost network growth

With its ability to support voice, data, video, and facsimile, the VSATPlus II terminal is an ideal modular system. It supports a full complement of information transport applications including low and high-speed data, multichannel high-quality voice & facsimile and two-way videoconferencing - all in a single, integrated, fully digital network.

Network Management System:
The product line also includes StreamView™, a comprehensive software-based network management system (NMS). StreamView allows operators to monitor and control an entire VSATPlus II network from a single location.

Network services:
Services supported include: interactive voice, data, facsimile, videoconference, LAN interconnect, WAN service, email, high-speed imaging and backup circuits for terrestrial links.

A range of RF and antenna subsystems:
These subsystems complete the VSATPlus II product line and permits network operation on C-Band, extended C-Band, INSAT and Ku-Band satellites.

VSATPlus II architecture:
This architecture is based on a combination of TDMA and frequency hopping and has unique attributes with significant advantages over most other VSAT architectures for the markets targeted. These markets are characterized by requiring four or more voice channel equivalents at each remote site and requiring wide flexibility of network configurations and service combinations. The product is ideally suited for applications requiring or benefiting from a direct digital interface.

StreamView Network Management System

StreamView’s major features and capabilities include:

• Centralized network management
• Remote terminal management (diagnostics, control and configuration)
• Dynamic bandwidth management
• Context sensitive on-line help
• Software download to one or many terminals
• Dial plan download to one or many terminals
• Hierarchical network management by one or more operators
• Alarm and event handling Real-time traffic analysis
• Call detail record collection for billing
• Remote network management via dialup modem

StreamView enables an operator to administer every aspect of his VSATPlus II network through a user-friendly windows-oriented graphical interface.

Flexible Network Management

StreamView enables an operator to define the VSATPlus II network’s parameters and connectivity. The operator can also monitor, control, configure and download software to individual terminals or groups.

StreamView also supports multiple operators by partitioning and subsequently restricting access to specific network management functions according to the operator’s level.

In a large VSATPlus II network, for example, StreamView could have two operators, one with full system administration and diagnostic control, and another with the ability to monitor or view parameters but not to change or modify them.

Full-Featured Network Management

StreamView supports each VSATPlus II terminal in the network with status polling, alarm handling, operator control and summary displays. An operator can issue commands to individual terminals or groups and StreamView displays the responses for evaluation and action. An operator can generate printouts of these displays and logs for each VSATPlus II terminal.

StreamView time stamps and records any alarm and status changes in the VSATPlus II network. The alarm and event logs, along with an audible alarm and icons to indicate alarm and status changes, assist an operator in tracking and managing network resources. StreamView also supports real-time traffic management functions that generate reports and graphs.

Windows-Oriented Graphical User Interface

StreamView’s easy-to-use graphical user interface is arranged as a series of hierarchical windows and icons to facilitate the management of the VSATPlus II network. An operator can navigate through these windows to configure network and individual terminals, manage maps, administer passwords, display and acknowledge alarms and events or generate reports. Screen navigation, online help, and system messages are organized to simplify network management operations and to reduce operator error.

Remote StreamView

An optional feature of the Network Management System is the ability to have remote workstations which have access to some or all of the features available on the primary StreamView Server. The StreamView NMS allows multiple remote users to connect into the StreamView Server.

Traffic Management and Call Detail Records StreamView Options

The Traffic Management and Call Detail Records options are a powerful toolkit to assist the network operator in managing and optimizing overall network performance.

VSATPlus II Terminal

The StreamView Network Management System is one of the most comprehensive network management systems ever designed for the satellite communications market. An element of PolarSat’s VSATPlus II product, StreamView integrates powerful monitor, alarm and control functions with an easy-to-use graphical user interface.

StreamView’s major features and capabilities include:

• Centralized network management
• Remote terminal management (diagnostics, control and configuration)
• Dynamic bandwidth management
• Context sensitive on-line help
• Software download to one or many terminals
• Dial plan download to one or many terminals
• Hierarchical network management by one or more operators
• Alarm and event handling
• Real-time traffic analysis
• Call detail record collection for billing
• Remote network management via dialup modem

StreamView enables an operator to administer every aspect of his VSATPlus II network through a user-friendly windows-oriented graphical interface.

Indoor Unit

The VSATPlus II indoor unit provides the interface points for customer communication equipment and performs the signal processing required for communication via a geosynchronous satellite.

The Modem Card, common to both terminal sets, is available in a nonredundant configuration or for the VSATPlus IIe, an optional redundant configuration. In all configurations, a chassis contains all the plug-in cards and power supply modules. These plug-in interface cards receive and transmit signals between the customer’s terrestrial equipment (such as telephones, computers, fax machines, and/or video equipment) and the outdoor unit. Additional terminals may be added to provide space for additional interface cards. chassis is a compact cabinet that can be set on a desktop or mounted in a standard rack. The indoor unit consists of a chassis with enclosed plug-in cards and power supply(s).

Desktop VSATPlus II indoor unit contains the following functional assemblies:

• Chassis with integrated power supply assembly
• Modem Card
• Interface cards

VSATPlus IIe chassis configured for nonredundant operation contains:

The VSATPlus IIe has a 19-inch rack-mountable chassis, which contains slots for up to:

· Ten interface cards

· One Modem Card

· One power supply

VSATPlus IIe Chassis Redundant configuration:

The VSATPlus IIe has a 19-inch rack-mountable chassis, which contains slots for up to:

· Ten interface cards

· Two Modem Cards

· Two power supplies

Modem Card

The VSATPlus II terminal uses a four-phase burst modem with absolute FEC encoding and decoding. The modulation technique is quadrature phase-shift keying (QPSK). The modem incorporates the latest concepts in digital modem and microprocessor control technology. It can be used with 70-MHz IF satellite communications equipment to allow the simultaneous transmission and reception of digital information via satellite. Users may select the modem bit rate via software control in 16 kbps increments from 512 kbps to 10 Mbps (including FEC bits). Included as part of the modem digital circuitry is the FEC (Forward Error Correction) circuitry.

Different user circuits may operate at different FEC rates within the same node and network. This arrangement provides a network operator with maximum flexibility for optimizing network efficiency and performance.

To provide better BER performance, FEC is automatically applied to the signaling channels as well as to the customer’s traffic. Other features include:

· Automatic gain control (AGC)

· LPC

· Optional performance monitoring on live data

The Modem Card implements the common-signaling channel that provides the interterminal signaling to support network reconfiguration, terminal control, and demand-assigned operations. The Modem Card also performs selected self-diagnostics, detects faults automatically and initiates automatic switchover as needed.

Interface Cards

Various cards provide the interface between the customer’s terrestrial equipment and the VSATPlus II terminal (and ultimately, to the satellite network). Individual plug-in cards connect voice, data, facsimile, and video signals to meet specific user requirements. The Modem Card and all interface cards are completely interchangeable between the VSATPlus II and the VSATPlus IIe.

In other words, you can upgrade from a VSATPlus II to a VSATPlus IIe by changing only your chassis: no card changes are necessary. This feature allows the user to reconfigure the network to best fit the traffic. Moreover, if a new traffic requirement evolves, either an existing interface card or a newly designed card can meet this new requirement.

Frame Relay Card

The Frame Relay interface is based on Frame Relay Forum (FRF) standards and recommendations, thus simplifying installation/ configuration issues and providing a seamless satellite-based extension to corporate and public telecommunications networks. The FR functionality is supported on an interface card that is added to any of the terminals in the VSATPlus II product line and will interface to standard routers, FRADs and data switches. Full configuration and control of the Frame Relay capabilities are provided by the StreamView NMS which can be connected to any terminal in the network.

QoS (Quality of Service) and Congestion Management are key attributes of Frame Relay that are supported by the VSATPlus II Frame Relay feature thus allowing real-time applications (such as Voice and videoconferencing) to be combined with less time-sensitive data applications. PolarSat’s Frame Relay interface is a unified platform that supports multiple service applications required by today’s communications networks such as IP traffic, LAN-LAN interconnectivity, database/Internet access, PSDN/PSTN interconnections, videoteleconferencing, datacasting, and voice/FAX applications.

Virtual private networks (VPNs) are created through the use of distinct DLCI assignments for different customers. User traffic is routed over each DLCI to any destination within the network. A DLCI can be a point-to-point or point-to-multipoint connection and user traffic can be balanced or asymmetric.

Satellite bandwidth is allocated through CIR, EIR, and QoS definitions and optimized using dynamic bandwidth allocation (BoD) techniques, thereby minimizing the recurring cost of operating a communications network. This approach provides user circuits with guaranteed bandwidth and the ability to request more from the network.

Many factors, associated with both the TDMA and the VSATPlus II, make the PolarSat product an excellent choice for telephony trunking applications. In addition to the inherent technological advantages of TDMA, such as full-mesh connectivity, hubless operation and automatic uplink power control, a key VSATPlus II feature is the E1 card. The E1 card provides a direct digital connection to private automated branch exchanges (PABXs) and switches. A variety of signaling protocols are presently supported and new protocols can be easily implemented because of the card's flexible software architecture. The following sections describe how these features work with a variety of signaling protocols.

PAMA Operation
When there is intense traffic concentration at the terrestrial interface point and when bandwidth requirements are fairly constant, preassigned circuits are often used for high-volume trunks between major switching centers. However, many times the number of interswitch trunks needed to support this traffic is less than a full El span (30 circuits). For such cases, the VSATPlus II's E1 card offers split channel mode and fractional El operation, which saves in hardware costs and conserves satellite bandwidth.

Fractional E1
The El interface card splits the El data stream into 30 independent channels. Any one, several, or all of these channels may be transmitted to any other node, in any order, where they are reframed and transmitted to the user. Because the channels are independent from each other, only the active channels of the El data stream are transmitted over the satellite by the VSATPlus II terminal.

DAMA Operation
VSATPlus II supports demand assigned (switched) service with standard line and register signaling protocols for voice service. It also operates as local exchange or toll-class switch (for example, class 4/5 switch) and allows private automated branch exchanges (PABXs) to connect without modification. DAMA operations reduce the number of required terrestrial circuits and total satellite channels. DAMA operation is decentralized. The failure of any station will not affect the operation of the rest of the network.

Transparent Mode
The E1 card can operate in transparent mode. In a 32-channel transparent mode of operation, the E1 card transparently passes 2.048 Mbps data. The card retains the terrestrial interfacing characteristics of the E1 card, but it does not require multiframe alignment (MFA) signals and does not support split-channel operations.

Network Management
When the VSATPlus II network is configured with the StreamView NMS, including the optional DAMA service management feature, the StreamView can provide DAMA network traffic information as one of the variety of advanced management features.

Voice Compression
The E1 card supports a variety of voice compression algorithms. Clear channel 64 kbps PCM is supported as well as 16, 24, and 32 kbps adaptive differential pulse code modulation (ADPCM) algorithms. Furthermore, emerging ITU standards for lower rate encoding schemes, such as G.729 (8 kbps CELP) and G.728 (16 kbps LD-CELP), are being developed for the E1 card as well as the associated subscriber analog voice card. Added features of the voice compression algorithms are fax and in-band data bypass support. Group III fax signals are supported up to 14.4 kbps. This means that in a 16 kbps compressed voice channel, 14.4 kbps fax transmissions can be sent. Without such a feature, fax signals would be severely distorted by the compression algorithm.

Protocol Spoofing
A major challenge of satellite-based telephony networks is the need to minimize the call setup delay. PolarSat has elegantly overcome this problem through protocol spoofing. The overall effect reduces the call setup delay caused by the satellite link to approximately three seconds!

Protocol Conversion
The line and register signaling protocol is optimized for satellite and TDMA operation. It creates the engine that implements universal protocol conversion, reformatting the line and register signals into a generic form. Using protocol conversion, VSATPlus II technology allows different switches to operate within the same network.

Voice Card

The voice card supports four channels of analog voice communications. It also provides the interface between the VSATPlus II system and a customer's
telephone network.

• Preassigned Multiple Access (PAMA) or Demand-assigned Multiple Access (DAMA) operation·
• The Voice Card may be used in the PAMA and DAMA modes of operation. PAMA provides   a full-period connection. In the optional DAMA mode, a pool of satellite channels is available for a channel to be allocated on demand. When a call is terminated, its channel is returned to the pool for reassignment
• Dual-tone Multifrequency (DTMF) or dial-pulse signaling
• Encoding rates
• The voice card encodes and decodes audio using:

o 64 kbps PCM in accordance with ITU-T G.711

o 16, 24, or 32 kbps ADPCM in accordance with ITU-T G.726

o 8 kbps CS-ACELP in accordance with ITU-T G.729A (voice encoding module (VEM) option)

• FXS/FXO interface signaling (option)

• The Voice Card supports FXS/FXO interface signaling with loop-start or ground-start reverse battery operation. The Voice Card includes an onboard, ringing voltage generator.

The Voice Card uses optional FXS or FXO plug-in modules (PIMs) to provide subscriber-loop signaling:

o The FXO PIM provides an office-end interface to connect to a PBX; it also offers reverse battery supervision as a user-selectable option.

o The FXS PIM can be connected directly to a subscriber set; it also offers reverse battery supervision as a user-selectable option.

• With the addition of the FXS PIM, the Voice Card supports 16-kHz metering pulse operation for connection to pay phone terminal equipment.

• 2-Wire subscriber loop (FXS)

A subscriber loop connects subscriber terminal equipment directly to the voice card within the VSATPlus II node. This subscriber terminal equipment includes rotary telephones, push-button telephones, fax machines, and modems.

• Onboard echo cancellers

The voice card contains onboard echo cancellers with automatic tone disable. Echo cancellers are automatically disabled when a tone is received from a fax machine or modem.

• Loopback diagnostics

Local and remote loopback diagnostic tests are available for testing the voice card's 4-wire E&M signaling. Both tests are individual channel loopbacks; each of the four channels can be individually tested. The local loopback checks the terrestrial access circuit and terrestrial interface. The remote loopback checks the entire card/channel data path, end-to-end, with the exception of the terrestrial interface in the remote card/channel.

• E1 Card compatibility

The voice card is compatible and interoperable with the E1 Card for demand-assigned circuits.

• Channel-level enable/disable

This function blocks the selected channels or all four channels on the voice card suitable for maintenance or testing purposes.

• Fax bypass (option)

The fax-bypass capability is provided for channels.

• E & M Interface

• 2- or 4-wire Type I-V E&M signaling with the addition of the E&M PIM, the voice card supports 2-wire or 4-wire voice frequency (VF) with Type I-V E&M signaling.

• ITU-compliant, fully compelled analog R2 signaling with several national variants

• Dial-up data (option)

The voice card, when configured for dial-up data operation, emulates the physical and electrical interface of a Hayes modem. With this option, you can use the Hayes AT command set to connect terrestrial data terminal equipment (for example, personal computers or asynchronous devices) by dialing through any other dial-up data port in the network. A dial-up data option call is established using the same Demand-assigned Multiple Access (DAMA) call setup used for voice card DAMA calls.

Data Card

The PolarSat data card is designed for use with the VSATPlus II and the VSATPlus IIe Version 2 systems and supports two channels of digital data communications.

The data card is transparent to customer data; that is, it does not check or process any information that may be contained in the data. In the case of control signaling, the data card performs handshaking (for example, RTS and CTS) with the local communications equipment and then passes the control signals to the far-end interface card.

• Multiple data rates:
  The data card supports rates ranging from 2.4 kbps to 512 kbps.
• Different data communication interfaces:
  EIA-449, EIA-232, and ITU-T V.35 data communication interfaces are available. The interfaces can be selected to emulate either DCE or DTE.
• Master or slave timing:
  The data card can be set to operate as a master (providing clock to user) or slave (accepting clock from user).
• Independent channel operation:
  The two channels operate independently in terms of destination interface card/channel, data rate, timing/signaling and loopback mode.
• Simplex or duplex operation:
  Both simplex and duplex operation are supported.
• Asymmetric bit rate handling:
  Bit rates within a single channel may be asymmetric (e.g., 1.536 Mbps receive and 64 kbps transmit).
• Downloadable software:
  A downloadable, nonvolatile version of the data card program can be stored in memory. These program versions can be remotely downloaded by the StreamView operator from the NMS.
• Loopback diagnostics:
  Local loopback and remote loopback diagnostic tests are available for testing the data card. The remote loopback checks the entire interface card/channel data path (end-to-end) with the exception of the terrestrial interface in the remote interface card/channel.
• Data Line Multiplexer Option:
  PolarSat's Data Line Multiplexer (DLM) enables customers with underlying star network topologies to support point-to-multipoint services or applications and to eliminate the requirement for a dedicated multiplexer at each remote site.