FIELD OF THE INVENTION:
The present invention generally relates to the field of Internet and intranet telecommunications. More particularly, the present invention relates to a network telecommunications appliance and system for Internet/ intranet communications.
BACKGROUND OF THE INVENTION:
US patent Publication No. 2004264433 discloses a method for wireless transmission between a first unit AP and a second unit MT. A predefined header compression technique (IETF ROHC) is then applied to the each encapsulated packet.
Korean patent Publication No. KR20090055117 (A) teaches to a header compression device in a broadband wireless connection system and a compression method thereof to reduce the wastage of bandwidth by classifying header compression and a convergence sublayer and communicating the header compressed packet.
US patent Publication No. 20100002690 describes a packet-based voice communication system for use over the Internet and intra.net telecommunications networks.
US Patent No. 6,970,909 describes a network telecommunications appliance and system supporting both wired and wireless network telephony services. A PBX based on the current network appliance can communicate with traditional phones through an Internet Telephony Gateway (ITG). Such a gateway connects to the PSTN using either analog lines, ISDN basic or primary rate interfaces or digital trunks (such as Tl/El). ITGs have recently been introduced as commercial products, with various capacities for example,

about 240 lines. The system includes one or more network telephony appliances which preferably operate in accordance with SIP protocol. The SIP network appliances are coupled to a data network, such as an Ethernet based intranet, and generally operate in conjunction with one or more SIP proxy servers which can be used as redirect servers and can provide enhanced functionality.
US Patent No. 7,657,021 teaches to a process for servicing a contactor in a contact center, in particular to servicing a contactor in a global call center. The wide area network is commonly packet-switched and employs one or more of the TCP/IP suite of protocols, the Session Initiation Protocol or SIP, and/or the H.323 protocol. To conserve the bandwidth, packeted voice and/or music transmitted over the WAN is compressed using a suitable compression algorithm, such as the G.711 and G.729 codecs and RTP header compression. Each of the agent communication devices can be one or more packet-switched and/or circuit-switched communication devices. For example, the devices can be Avaya Inc.'s, 4600 Series IP Phones.TM., IP softphones such as Avaya Inc.'s, IP Softphone.TM., Personal Digital Assistants or PDAs, Personal Computers or PCs, laptops, H.320 video phones and conferencing units, voice messaging and response units, traditional computer telephony adjuncts, and wired and wireless circuit-switched telephones.
The technical literature entitled "Private Mobile Networks - Private GSM and IP Solutions", published by Private Mobile Networks Ltd discusses about Fixed Mobile Convergence. PMN enables mobile phones to become part of the internal telephony infrastructure while near the workplace. Users are able to access the same services and features using a fixed

extension on the corporate PBX or on their mobile phone. PMN can' be implemented either by replacement of the PBX or by integration with the existing PBX infrastructure. Use of applications on the mobile phone can be simplified using Mobile Office software which provides a menu-based interface to conferencing, call recording and call transfer and delivers this functionality to mobile handsets even when roaming.
The technical literature entitled "Low-cost telephony via cellular networks provided in bundled solution", published by Hypermedia Systems talks about Asterisk®-based IP-PBX from Xorcom bundled with gsm gateway from hypermedia providing low-cost telephony via cellular networks.
The technical literature entitled "The Open BTS Project" teaches an open-source Unix application that uses Universal Software Radio Peripheral (USRP) to present a GSM air interface ("Urn") to standard GSM handset and uses Asterisk software PBX to connect calls. The combination of the ubiquitous GSM air interface with VoIP backhaul forms the basis of a new type of cellular network that can be deployed and operated at substantially lower cost than that produced under existing technologies.
The technical literature entitled "Asterisk-based IP-PBX device adds GSM option" describes Pika's new GSM Module. The module provides two GSM channels or radios per module and uses two externally accessible SIM cards. It can also work in combination with other Warp Appliance expansion modules, such as the analog trunk (FXO), analog station (FXS), and BRI modules. (See farther below for more details on the Warp Appliance and Pika's new Warp Enterprise distribution.) The GSM Module supports 3V and 1.8V SIMs, as well as incoming and outgoing voice calls for PBX, auto attendant, integrated voice response (IVR), and other telephony applications.

The technical literature entitled "GSM Gateways" discloses FCT Fixed cellular terminals (premicells) and GSM gateways that have traditionally been used for reducing call charges to mobile phone networks. The FCT / GSM gateway connects to a telephone system / PBX and uses a standard mobile phone SIM card to make calls directly over the mobile phone network. The tariffs available from mobile phone companies make calling mobile phones on all networks highly cost effective.
The technical literature entitled "GSM Gateways" technique which is quite different from ROHC Technology. In "GSM Gateways", the telephone calls are routed directly to cellular network instead through Fixed-Line-Provider to restrict call charges. However, the amount of data carried for voice is same for each calls. According to gateway manufacturer 2N, companies can lower their fixed-to-mobile call costs by at least 50% without compromising on voice quality.
In ROHC technique, a huge amount of data is saved by compressing the data and reducing the bandwidth. It is known that for using a fixed bandwidth for example, "GSM Gateways", a fixed amount of call charges need to be paid whether or not the caller uses the full bandwidth for all calls through the gateways. ROHC compresses 40 bytes (for IPv4) into 1 byte and 60 bytes (for IPv6) into 3 bytes by placing a compressor before the link and a de-compressor after that link. It is possible to compress those headers, leading to more than 90% savings including an efficient use of the expensive resource. IP header compression also provides other important benefits, such as reduction in packet loss and improved interactive response time. The global Cellular standardization Authorities like 3GPP and 3GPP2 have adopted the ROHC standard. The ROHC scheme is recommended in next generations of the 3GPP standard. The IP-based
Multimedia Subsystem (IMS) to be introduced in the latest generation of protocol is based on IPv6 only.

The IPv6 header itself being 40 bytes and together with UDP/RTP totaling 60 bytes substantially increases the overhead for voice and video applications. It is essential to save the bandwidth, reduce the packet loss due to bit errors and reduce delays due to these large overheads. The ROHC header compression becomes indispensable to improve user experience of services and save the expensive radio resource.
According to the 3GPP standards, the function of ROHC header compression operates partly on the mobile device and partly on the radio network controller (RNC). As per the 3GPP2 standards, the ROHC header compression further operates partly on the mobile device and partly on the packet data switching node (PDSN).
The ROHC framework therefore, defines 3 modes of operations
The selection of a mode is based on parameters such as availability of feedback channel, error probabilities and header size variations. The operators of the network may reject use of a channel to carry feedback packets for various reasons and thus limit the mode of operation of .the ROHC. The following three modes have been defined:
Unidirectional mode (U-mode)
In this mode, packets are sent in one direction, from the compressor to the decompressor. In cases where the return path or the reverse channels are not available, ROHC can still be used. If the return path or the feedback channel is available, it is used by the decompressor to acknowledge successful decompression.

• Bi-directional Optimistic mode (O-mode)
In this mode, the decompressor sends feedback in the form of requests for error recovery (negative acknowledgements, NACKs) and indication of successful context update (acknowledgements, ACKs) This mode yields higher compression gains while making sparse use of the feedback channel and it reduces the packet loss due to the context invalidation.
• Bi-directional Reliable mode (R-mode)
In this mode, the feedback channel is used quite often to avoid packet loss due to context invalidation. R-mode uses the secure reference principle rather than the optimistic approach as in other modes. In secure reference principle, confidence of the compressor depends on acknowledgements from the decompressor for every context updating packet. However, not every packet in R-mode updates the context.
OBJECTS OF THE INVENTION;
It is therefore, an object of the present invention is to propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data.
Another object of the present invention is to propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data, which is capable of directly or indirectly calling another network telephone station party.

A still another object of the present invention is to propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data, which enables FEC (Forward Error Correction) to provide the best Quality of Service (QOS) on speech to an user.
Yet another object of the present invention is to propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data, which allows organizations with special requirements from a PBX system the solutions to their existing constrauts, by deploying some of the extensions on handheld/mobile devices.
Another object of the present invention is to propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data, which provides resilience critical applications such as but not limited to disaster recovery sites for railways, army etc.
A still another object of the present invention is to propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data, which provides a cost effective solution for provisioning of telephone services in rural areas. Yet another object of the present invention is to integrates propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data, which pre paid and post paid billing solutions to reduce cost for each type of service.

A further object of the present invention is to propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data, which is applicable for fixed and mobile telephony convergence, and which supports any telecom protocol used in a public or private network.
A still further object of the present invention is to propose a system and a method for extending the networking coverage by integrating handheld/mobile devices operating as PBX extensions with PBXs and to conserve bandwidth by compressing packet data, which can handle various telecom connectivities including but not limited to Voice Data, Video, SMS, GPS & GPRS based services. At the outset of the description that follows, it is to be understood that the ensuing description only illustrates a particular form of this invention. However, such a particular form is only an exemplary embodiment and is not intended to be taken restrictively to imply any limitation on the scope of the present invention.
SUMMARY OF THE INVENTION
According to the present invention, there is provided a system and a method across a wired or wireless network composed of any combination of access devices for example, PoTs/ Quad Cable based railway Connectivity's and weigh bridge applications of Railways (MCCS) and conserve bandwidth by compressing data in packet form using a compression algorithm. The system proposes a fixed mobile communication solution that provides a solution for prior art disadvantages including enhanced usage of the common services. Hand held devices fully integrated with an enterprise PBX can reduce costs with the least cost routing (LCR) feature, and provide mobility voice services

to every user thereby replacing expensive DECT or Tetra or Cordless telephone systems. Every call is routed through the least expensive route by an intelligence built into the PBX.
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
Figure 1 shows a block diagram according to the present invention.
Figure 2 shows a flowchart of the inventive system in a communication mode between an internal mobile to another internal mobile.
Figure 3 shows a Flow-diagram of the system with a distributed or centralized call processing.
Figure 4 shows the architecture of the present invention with common control section.
DETAILED DESCRIPTION OF THE INVENTION
Reference may be made to the figure 1 which provides a system and a method for extending the networking coverage using handheld/ mobile devices operating as PBX extensions where the communication over wireless media is of conserved bandwidth by compressing the transmitted data by using a suitable compression algorithm for seamless call control for calls across any communication channel/ network by bundling PBXs with mobile devices as wireless extensions of the PBX as an in-building/ defined area solution with a central control.

The present invention provides system which adapts ROHC (Robust Overhead Compression) based technique for compression over Time Division Multiplex (TDM) circuits. The ROHC compressor replaces the RTP/UDP/IP headers by its own, much smaller header. On the receiver side the de-compressor transforms the ROHC header into the original protocol layer headers.
As shown in figure 2, the data between users inside the private GSM network used either as Call/SMS/GPRS has been compressed by a predefined header compression technique (IETF ROHC) which is then applied to the each encapsulated packet.
The compression technology is used over the legacy circuit wherein such compression also caters to FEC (Forward Error Correction), thereby enabling the subscriber to have the best QOS on speech. As the present solution is catering to the IP as well as the legacy TDM system, this compression algorithm developed is very useful over TDM to TDM networks and also maintains the actual QOS. The existing systems have ROHC over IP and not over TDM. ROHC supports three different modes for maintaining the context in different wireless systems. The unidirectional mode is designed for systems without a feedback channel from the de-compressor to the compressor, i.e., where the de-compressor cannot acknowledge the correct receipt of context information. To overcome this limitation, the compressor periodically retransmits the context information. The bidirectional optimistic mode and the bidirectional reliable mode are designed for systems with a feedback channel from the de-compressor to the compressor, i.e., where the de-compressor can acknowledge the correct receipt of context information and/or send negative acknowledgements to request the retransmission of context information. With the bidirectional optimistic mode, bit errors in the compressed header are detected with a 3-bit cyclic redundancy check (CRC) code. When the CRC check fails the de¬compressor generally discards the

affected packet and attempts to repair its context either locally or by requesting a context update from the compressor. The reliable mode extends the optimistic mode by a more complex error detection and correction which uses a larger' number of coding bits. Below Fig illustrates ROHC mechanism.
The system of the present invention as shown in figure 3 acts a soft switch at the core that can support multiple locations with a distributed or centralized call processing architecture hence can act as a hosted solution that can work across geographically located offices.
According to the present invention, the system of the invention as shown in figure 4, works with a common control section in synchronization with' all the protocols connected. It means, all the protocols run on one common platform without any hindrance. GSM phones can talk to Analog phones and Digital phone and vice versa. The common call control and management supports the base station controller (BSC) and the mobile switching center (MSC) functionalities with an integrated HLR function so as to support GSM applications for private networks. R.A.N (Radio Access Network) is integrated with the system to provide a cost effective "private GSM network". The proposed solutions offer a choice of network layouts, where MSC & BSC are in one box but not limited to and BSC is communicating with MSC for call control. Communication between MSC to BSC & BSC to BTS (Base transceiver station) is on Ethernet. Antenna is connected to the BTS by Radio'Frequency (RF) cable.
The present invention provides Common Embedded Control Card to switch Voice, Data and Video calls from any protocol to any protocol and over any media to any media. It means system can be connected with outside world via any media El / PRI / E&M / TWT / IP Trunks on the network side.

Support from common control cards will include but not limited to Voice Data Video, SMS, GPS & GPRS based services.
The system supports all functions of intra office Unified Communication, voice mail, IVR application. They are done by installing the required UCS software/package in the system. Once they are functional, all aforesaid applications run on common platform. They will seamlessly operate in a networked environment across different geographic locations & can' be supported over central/ duplicated or distributed Server architectures of IRIS NGX technology. Features like call conference, Call forward, flexible numbering plans & CUG groups will work like in any other enterprise communication network.
The system has an embedded MSC that supports up to 50 Micro Air BSS (BSC & BTS - Trxl Super Pico) which interalia enables an user to extend upto 50 Trx BSS from one central location. Each of these can be connected on IP.
The air solutions are RAN based which is enabled to support multiple frequencies simultaneously, wherein the network can be shared by several service operators/ providers as an "in building" solution. It requires that the coverage foot print of the common power amplifiers/ common antennae be the same for each telecom companies who are sharing the active infrastructure. Server has virtual partitioning for each operator.
The system supports common control which facilitates seamless feature availability for Call transfer/ Call Forward/ Least Cost Routing (LCR)/ Unified Messaging System (UMS)/ Pre-paid and Post Paid Billing/ Conference Facilities/ Automatic Call Distribution (ACD) in a Call Center Environment. It is adaptable to any protocol such as but not limited to El, PRI, E&M, Magneto/ IP/ SIP/ MGCP/ MAGACO/ Quad cable/ UHF/ VHF sets/ TWT / BWT/ MSC/

BSC functionality in a single box solution where switching is supported across plurality of protocols.
Accordingly, the present invention provides a TDM based "Conference Bridge" across different protocols to ensure that at the time of sampling, the system transmits the highest level of speech signal. This ensures optimal conversation on a conference across such a diverse set of protocols. The central control switch is multiplied deactivated, and/or reconfigured to have an additional level of control from geographically distant servers. The system is enabled to operate on 12 V / 24 V / 48 V batteries so that even if some batteries fail in the rural environment, the system still continues its operation.
The present invention provides a solution by operably synchronizing wire-line legacy PBX system with GSM handsets, wherein the PBX wired extensions are converted into Wireless handsets by usage of DUAL Sims. The system is configured on ROHC based technique for compression. Seamless switching over such a wide variety of protocols and connectivity is not available in the prior art.
Accordingly, the invention provides a common control and monitoring system that will handle all control functions for ADSL connectivity over wired subscribers and GPRS services to 3G / LTE based mobile devices. They are done by routing all IP packets' over ADSL. ADSL is commonly known as broadband internet service.
A common control card provides SMS & GPS based services for all mobile and wired subscribers seamlessly.

The network also service mobile roaming subscribers of one or more city wide mobile operator so that the RF frequency within the building/ Campus can be most optimally utilized. Roaming subscribers may or may not be allowed to interoperate with the private subscribers of the network.
It is to be understood that the above-described embodiments are illustrative of only a few of the many possible specific embodiments, which can represent applications of the principles of the invention. However, numerous and varied other arrangements can be readily devised in accordance with these principles by those skilled in the art without departing from the spirit and scope of the invention.

WE CLAIM :
1. A system for seamless call control of voice calls across communication networks by bundling PBX with mobile phones acting as extension of the PBX, comprising :
- at least one Base station controller (BSC) and at least one mobile switching center (MSC) disposed within a single box in which the BSC is communicating with the MSC for call control;
- a common control section embedded in synchronization with all the communication protocols allowing GSM including analogue/digital phones to communicate with each other;.
- an antenna connected to a base transreceiver station (BTS) by radio frequency (RF) cable;
- Radio access Network (RAN) is integrated to the system to act as a private GSM network;
Characterized in that the system is incorporated with UCS software package and adapts a Robust Overhead Compression (ROHC) based technique for data compression over Time Division Multiplex (TDM) circuits.
2. The system as claimed in claim 1, wherein the system is enabled to
operate on 12V/24V/48V batteries.
3. The system as claimed in claim 1, wherein the PBX wired extensions are converted into wireless handsets by the dual Sims.