ARRANGEMENT IN A COMMUNICATIONS SYSTEM
FIELD OF INVENTION The present invention relates to an arrangement in a communications system according to the preambles of the independent claims. More specifically it relates to a communications system for home and small office and to a gateway and an application server within said system.
DESCRIPTION OF RELATED ART
Today's existing radio technologies are, depending on frequency band, modulation method and bit rate, optimised for specific applications and interfaces. For multi-service delivery in the residential environment, wireless communication is desired for both high-speed data communication, including voice and video, and for automation, monitoring and control purposes.
The requirements of communication characteristics and performance for the various purposes differ significantly.
For automation monitoring and control purposes, characteristics such as long range, good Radio Frequency (RF) penetration of building constructions, ability to handle large number of nodes within a limited area, robust and secure communication, at extremely low power consumption are important, while maximum bit rate and high capacity at moderate range are driving requirement for data, voice and video communication.
Existing solutions have either resulted in separated systems, optimised for specific applications, or shared access systems, e.g. HomeRF™, where a higher degree of complexity adds a significant cost burden to the low end, cost sensitive automation devices.
An example of a system for residential environments is known from WO0041529, from now on called Dl. The system which is a Local Area Network (LAN), has access to voice and data communications to the Public Switched Telephone Network (PSTN) via a so-called Network Control Unit (NCU) which constitutes a gateway within the system. The network comprises a number of Wireless Access Units (WAU), a number of handsets and conventional telephones and other electronic devices such as fax which all are connected to the gateway. The principle of this system is to distribute intelligence closer to the user level and promote the telecommunications network, which requires less centralised command and control. A problem is that the implementation of automation, monitoring and control devices is expensive and the units consume too much power to be permanently battery operated.
A disadvantage with system according to Dl is that the connection to the world around turns on the PSTN access. A PSTN dial up results in transaction costs and time delays. A real-time automation, monitoring or control application cannot be run on a remote server.
SUMMARY OF THE INVENTION
The object of the invention is to unravel the above mentioned drawbacks and provide an improved communications system for home and small office and to enable low cost terminal units.
This is achieved according to the method and arrangement set forth in the characterising parts of the independent claims.
Preferred embodiments are set forth in the dependent claims.
Thanks to that the gateway comprises a global interface to a broadband Internet access network, a wireless local interface to a high bit rate local area network, and a wireless local interface to a low bit rate local area network, and thanks to that the
application server manages the communication system in a centralised way, an improved wireless communications system for home and small office is provided and low cost terminal units can be used.
An advantage of the communications system according to the present invention is that it, for a home or small office, provides high bit rate for the fast data communication, a good radio coverage and a cheep cost for automation.
An advantage of the communications system according to the present invention is that it allows real-time automation, monitoring and control applications as well as communication management tasks to be run on a remote server.
Another advantage of the communications system according to the present invention is that it enables low cost terminal units for automation, monitoring and control.
Yet another advantage of the communications system according to the present invention is that it provides improved Radio Frequency (RF) coverage in buildings.
BRIEF DESCRIPTION OF THE DRAWINGS
Figure 1 is a diagram showing a communications system for a home or a small office, according to the present invention.
Figure 2 is a diagram showing an application server within the communications system according to the present invention. Figure 3 is a diagram showing a gateway within the communications system according to the present invention.
DESCRIPTION OF PREFERRED EMBODIMENTS
Figure 1 is a diagram showing a communications system for a home or a small office 100 according to the present invention. The system comprises a gateway 102 which gateway has a global interface to a broadband Internet access network 103, which enables communication to an application server 104. The gateway 102 has further two wireless local interfaces one to a high bit rate network 108 and one to a low bit rate network 110. The two latter are local area networks 108, 110 within a home or a small office. The two local area networks 108, 110 works at different frequency ranges and thus do not interfere in each other's traffic and capacity. The system is based on a layered protocol structure, e.g. selected parts of the Internet Protocol (IP) protocol suite, including protocols providing security. Examples of such protocols are Transmission Control Protocol (TCP), User Datagram Protocol (UDP), Network Address Translation / Port Address Translation (NAT/PAT), Internet Control Message Protocol (ICMP), Bootstrap Protocol (BOOTP), Dynamic Host Configuration Protocol (DHCP), Domain Name System (DNS), Point-to-Point Protocol over Ethernet (PPPoE), Address Resolution Protocol (ARP), Reverse Address Resolution Protocol (RARP), etc.
Application server 104
The application server 104 may be located within the Internet 106 at an Internet Service Provider (ISP) or an Application Service Provider (ASP) as illustrated in Figure 1, within the access network 103 or locally, either within a the gateway 102 or as a server connected to the local high rate network .108. The application server 104 is shown in Figure 2, and has means 204 for running automation, control and monitoring applications and means 202 for managing the communications system and the gateway 102 in a centralised way. It has further means 206 for providing the gateway 102 with important information such as which nodes within the local networks 108, 110 that are allowed to connect to the gateway 102. It further has means 208 for handling software download/upgrade, and means 210 for handling plug and play functionality etc. It may e.g. be an OSGi™ based server.
Gateway 102
The gateway 102 may be located inside or adjacent to the home or small office. It has a global interface to the broadband Internet access network 103 that enables communication with the application server 104. The global interface may be e.g. Ethernet 10/100 Mbps, cable television modem, a Digital Subscriber Line (xDSL- techniques) modem or any broadband, always on access network. The gateway 102 is shown more in detail in Figure 3. The gateway 102 has means 304 for being managed by the application server 104. The gateway 102 further comprises a firewall 302 towards the global interface to prevent unauthorised to gain control to local hosts (computers) on the local networks 108, 110 or to operate within the local networks, e.g. to prevent unauthorised to unlock a front door at the home. E.g. the NAT/PAT natural firewall may be used. The gateway 102 comprises a private local interface to a high bit rate network 108, and a first transceiver 116 for wireless communication with units 112 within said high bit rate network. The interface might be a WiFi™ 11 Mbps Wireless Local Area Network (WLAN) or a Bluetooth™ Personal Area Network (PAN) or future standards such as IEEE802.11a and Hiperlan/2. The gateway 102 might also comprise means 308 for allocation of local IP addresses to the units 112 within the high bit rate network 108, preferably Dynamic Host Configuration Protocol (DHCP) might be used. Manual configuration is also possible.
The gateway 102 further comprises a wireless interface to a low bit rate network 110, and a second transceiver 118 for wireless communication with units 114 within said low bit rate network. 110. This local interface is a proprietary gateway/protocol wrapper, from a proprietary protocol to e.g. the Simple Network Management Protocol (SNMP).
The gateway 102 further comprises means 312 for supervision and management of the units 112, 114 within the high bit rate network 108 and the low bit rate network
110. Remote configuration and management of the gateway 102 and the units 112, 114 within the networks 108, 110 is supported using e.g. the Simple Network Management Protocol (SNMP), HyperText Transfer Protocol (http) or Telnet. The gateway 102 also comprises means 310 for authentication of a remote management application e.g. by using Password Authentication Protocol (PAP) or Challenge Handshake Authentication Protocol (CHAP). Several secure protocol alternatives exist.
The gateway 102 has means 306 for obtaining, from the application server 104, important information such as which nodes within the local networks 108, 110 that are allowed to connect to the gateway 102.
High bit rate network 108 The high bit rate network 108 is a private local e.g. Wi-Fi™ 11 Mbits WLAN,
IEEE802.11b network. Other alternatives are Bluetooth™, IEEE802.11a and
Hiperlan/2 standards.
The network 108 comprises wireless units 112, associated to the home or small office, such as terminals and adapters to interface units or functions requiring high data rate, such as IP telephony, video, Personal Computers (PC) etc. wliich units
112 each comprises a transceiver for wireless communication with or through the gateway 102.
This is a standardised network and it is thus easy to obtain units.
Low bit rate network 110
The low bit rate network 110 is a proprietary two-way wireless low frequency network operating at a frequency which has been set aside by international agreement for the use of industrial, scientific and medical devices (ISM). The network has e.g. a bit rate of 10 kbit. One example of such network is HomeWave™.
The network 110 comprises autonomous wireless units 114, associated to the home or small office, such as sensor, input/output control, metering, remote control devices, etc. Each of the units 114 comprises a transceiver for wireless communication with or through the gateway 102. These units 114 do not require high data rate but rather extended communication range in indoor environments, including penetration of building constructions, as the units often must be located at hard-to-reach locations. Low frequency in combination with low bit rate provides significantly improved range and penetration at extremely low RF output power, compared to 2.4 and 5 GHz ISM bands. The low power enables devices to operate from batteries during several years without changing battery.
The present invention is not limited to the above-described preferred embodiments. Various alternatives, modifications and equivalents may be used. Therefore, the above embodiments should not be taken as limiting the scope of invention, which is defined by the appendant claims.