1. Field of the Invention
The invention is related to a virtual intranet based on a digital closed network, and more particularly to a virtual intranet which is established by the digital closed network over the Internet.
2. Description of the Prior Art
Since the VoIP (Voice over Internet Protocol) has the advantage of lower communication cost compared to the conventional telephone system and has the ability to integrate data, more and more enterprises employ the VoIP as their communicating means. Based on the established VoIP, the enterprise can simultaneously perform the voice, data and video signal transmission over the single IP platform. Therefore, not only is the internet management process simplified, but also the entire cost is reduced. With reference to
In the intranet architecture mentioned above, the extension (73) only occupies a part of bandwidth (for example, 4K) for voice signal transmission. However, whether using the conventional IP network or the LAN, the data signal (data packet) is the main transmission subject. The objective of the network architecture design still focuses on the improvement of the reliability, i.e. to make the data packet have the highest transmission priority during the transmission process. In such a condition, when a great amount of data is transmitted among these computers (71), the serious problems of voice signal transmission delay and jitter accordingly arise. However, for voice signals, the most essential requirement is immediate transmission (i.e. the real time transmission). Therefore, the poor transmission quality is obvious.
Since the conventional intranet configuration is unable to solve the delay problem of signal transmitting, one temporary way to improve the voice signal transmission quality and to alleviate the problem is by utilizing the broad bandwidth. However, when a great quantity of data is being transmitted, these data still cause delay to the voices and such a temporary solution is unable to completely overcome the problem. Besides, the intranet architecture mentioned above is composed of the computers, the hub, the extensions to transmit data and voice signals so the extensions are limited in this intranet architecture to communicate with each other. That is, no one extension can communicate with others in the same Internet configuration.
To overcome the shortcomings, a virtual intranet based on the digital closed network in accordance with the present invention obviates or mitigates the foregoing mentioned problems.
The primary objective of the present invention is to provide a virtual intranet based on the digital closed network, which is constructed by a network PBX and a key telephone system (KTS) to allow extensions that transmit the voice, data and video signals over the Internet or other LAN, MAN etc IP networks back to the other extensions, and still retain the superior voice transmission quality.
To achieve the objective, the virtual intranet is constructed of the network PBX, multiple extensions connected to the network PBX, wherein the network PBX and each telephone respectively have connection to an IP network capability to transmit IP packages over the IP network.
Each extension has a unique number, which is stored in the network PBX. The network PBX stores extension numbers, virtual IP addresses and at least one published IP address, and is set up with an identification method for automatically setting up extension numbers, virtual IP addresses and the published IP address to every extension connected to the network PBX. Therefore, when the registered extension is brought to another place the registered extension can be connected to a modem or an XDSL to link to the Internet. The registered extension stores the published IP address of the network PBX so the registered extension uses the published IP address to link back to the network PBX through the Internet. Therefore, the distant registered extension and the network PBX are constructed via the virtual Intranet.
Other objectives, advantages and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings.
With reference to
The network PBX (10) includes a main controller (11) and a packet switch (12). The packet switch (12) has at least two network ports (121, 122) for the IEEE 802.3 protocol to connect the extensions (20). The main controller (11) connected to the packet switch (12) stores multiple extension numbers for the extensions (20) and is set up with an identification method. The main controller (11) further stores multiple virtual IP addresses corresponding to each extension number. The network PBX (10) further comprises a packet processing unit (13) for two-way converting connected between the main controller (10) and an extra PBX (30) for PSTN (31). The packet switch (11) is set up with at least one published IP address for linking to the Internet through one network port (121) connected to a network device (not numbered) as a modem or an XDSL (not numbered).
The plurality of extensions (20) is able to connect to the network port (122) of the network PBX (10) with different topologies (as shown in
With reference to
Each extension (20) further includes a bridge (28) linked between the first network connecting interface (23) and the second network connecting interface (24) to perform the transmission flow control of the closed network.
From the foregoing description of the network architecture, the plurality of extensions (20) not only constructs the closed network in company with one network PBX (10), but each extension (20) is also used as an intermediary node that allows the personal computer, hub, network printer etc. to communicate with the closed network.
When the closed network is constructed, each extension (20) stores its own extension number, virtual IP address and the published IP address. Therefore, an establishing virtual intranet method includes the steps of:
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One special point that needs to be noted is when the voice signal is communicating over the closed network, the network will provide superior transmission quality. For example, if one extension (20) is used as a transmitter (the voice source), the input voice from the handset (22) is converted to the form of voice packets by the controller (21) and then transmitted over the closed network. After another extension (20), which acts as a voice receiver, receives and converts the voice packet to a voice signal by the controller (21), the voice signal is then broadcasted via the handset (22). Since the voice is transmitted in the form of voice packets, the problems of transmission delay and jitter are accordingly overcome. Moreover, by controlling the controller (21) and the bridge (28) to properly set the transmission priority among the voice packets, data packets and the video packets, the transmission quality is able to be further improved. In other words, because of the controllable transmission flow in the closed network, the real time voice transmission is assured.
In conclusion, the present invention providing a virtual intranet differs from the conventional the intranet limited in a specific place and together with the telephone system having packet conversion ability and bridge function collectively provides an immediate voice transmission, wherein the problems of delay and jitter are avoided. In addition, the network architecture of the present invention also meets the data transmission protocol (IEEE 802.3/302.11 x) to ensure that the data/video packets are correctly transmitted among all nodes of the network. In other words, the present invention still retains the high reliability for data/video transmission.
The invention may be varied in many ways by a skilled person in the art. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications are intended to be included within the scope of the following claims.