CN101478618B - External line state detection method for external switching center - Google Patents

Abstract

The invention relates to a Foreign Exchange Office (FXO) interface of an Internet Protocol (IP) speech communication device. The invention discloses a FXO interface outside connection detection method, and avoids a communication failure caused by the unavailable FXO interface outside connection. The invention judges whether the FXO interface outside connection is available or not by detecting that whether an outside connection loop current exists at different time intervals of the initialization, the calling and communication times. The detection method of the invention keeps the FXO interface pick-off and timingly detects the variance from the unavailable to available of the outside connection state after the initialization FXO interface for the detected unavailable FXO interface of the outside connection state at the initialization time, and detects the variance from the available to the unavailable of the outside connection state through calling or the pick-off during the communication after the initialization FXO interface for the detected available FXO interface of the outside connection state at the initialization time. The FXO interface outside detection method of the invention can be applied to the speech communication device with a plurality of FXO interfaces.

Description

External line state detection method for external switching center

Technical field

The present invention relates to FXO (FXO) interface of Internet protocol (IP) voice communication apparatus, particularly FXO interface line state detection method for external.

Background technology

Along with the continuous development of the communication technology, voice Internet protocol (VOIP) is more extensive in the application of the communications field.Because the IP network that extends in all direction, and advantages such as the low cost of ip voice communication, high efficiency, many value-added services, ip voice communication is more and more being used neighborhood and is being replaced traditional communication mode.

For the public switch telephone network of extensive use (PSTN), be fused to rapidly and reliably in the new IP communication network, the ip voice communication equipment has used the FXO interface, as FXO interface voice gateways and FXO interface router etc.On the basis that does not change public switch telephone network; by having the communication equipment of FXO interface; the PBX (PBX) that connects PSTN; ip voice communication equipment side user inserts PSTN as the plain old telephone terminal; the plain old telephone terminal of PSTN inserts IP network as the IP phone terminal use; realize the interconnection of PSTN network and IP network, protected the existing PSTN Internet resources of user simultaneously.The FXO interface is as the interface of IP network and PSTN, whether detect voice communication apparatus FXO interface connects intact to this section of PBX circuit, obtain the whether available testing result of FXO interface, for being registered to FXO interface communication equipment, the FXO interface resource provides foundation, being that FXO interface external line state detects, is the very crucial problem that needs solution.Otherwise when circuit breaks down, for example short circuit, when opening circuit, calling can not be successful, particularly when same equipment is integrated with a plurality of Analog Trunk Interface, the problem that also has the port gating, in case some or a plurality of analog ports be owing to the circuit reason can't be finished when calling out, because call attempt that will be one by one also can elongate call set-up time.

Summary of the invention

Technical problem to be solved by this invention, just provide a kind of FXO interface line state detection method for external, when the outside line of FXO interface is unavailable, FXO interface voice communication apparatus can be selected other available circuit for use, unlikelyly cause conversation failure because the outside line of this FXO interface is unavailable, thereby guarantee the reliability of ip voice communication.

The present invention solve the technical problem, and the technical scheme of employing is that external line state detection method for external switching center may further comprise the steps:

A. during initialization FXO interface, FXO interface off-hook is set;

The b.FXO interface detects whether there is the outside line loop current, and when detecting the FXO interface and have the outside line loop current, it is available the on-hook of FXO interface being set and FXO interface external line state is set; When detecting the FXO interface and do not have the outside line loop current, it is unavailable keeping FXO interface off-hook and FXO interface external line state is set.

Further, also comprise the steps:

C. for the disabled FXO interface of external line state, the FXO interface regularly detects whether there is the outside line loop current, and when detecting the FXO interface and have the outside line loop current, it is available the on-hook of FXO interface being set and FXO interface external line state is set;

D. the FXO interface that can use for external line state, from FXO interface External Call PBX the time, the FXO interface detects whether there is the outside line loop current, when detecting the FXO interface and do not have the outside line loop current, it is unavailable that FXO interface external line state is set, and returns step c; Perhaps, in normal talking, the FXO interface regularly detects whether there is the outside line loop current, and when detecting the FXO interface and do not have the outside line loop current, it is unavailable that FXO interface external line state is set, and returns step c.

The invention has the beneficial effects as follows, do not disturb the PBX that outside line connected of FXO interface, under the situation that does not influence the use of FXO interface, whether exist loop current to detect FXO interface external line state by the outside line of FXO interface off-hook detection, guarantee the reliability of ip voice communication; And FXO interface voice communication apparatus can solve some FXO interface outline faults, as faults such as FXO interface outside line bad connection, circuit damages timely by detecting outside line.

Description of drawings

Fig. 1 is an application network environment schematic diagram of the present invention;

Fig. 2 is implementing procedure figure of the present invention.

Embodiment

Below in conjunction with drawings and Examples, describe technical scheme of the present invention in detail.

When characteristics of the present invention are the branch initialization, when calling out with conversation in the different periods detect the external line state of FXO interfaces.During initialization FXO interface, FXO interface off-hook is set, by detect whether exist the outside line loop current detect the outside line of FXO interface can with or unavailable.Detect the disabled FXO interface of external line state during for initialization, after initialization FXO interface is finished, keep FXO interface off-hook and regularly detect external line state from being not applicable to available variation.Detect the FXO interface that external line state can be used during for initialization, after initialization FXO interface was finished, the off-hook by in calling or the conversation can detect external line state from using disabled variation.

FXO interface line state detection method for external of the present invention, testing circuit that need not be special does not need the FXO interface is done any circuit modification.By FXO interface basic circuit, according to the telephone line circuit theory, and the FXO interface has the function that detects the telephone line loop current, is connected just often with PBX at the FXO of off-hook interface, and the FXO interface can be discerned the loop current of telephone line formation; If the FXO interface and the PBX malunion of off-hook are normal, the FXO interface can identify telephone line circuitry can not form loop current, just can realize that in view of the above FXO interface external line state detects.Among the present invention, FXO interface off-hook or on-hook do not influence the PBX that connects by the outside line of FXO interface, do not disturb this FXO interface voice communication apparatus and other PBX equipment.

Embodiment

Application network environment schematic diagram of the present invention as shown in Figure 1.The ip voice communication equipment has used the FXO interface, on the basis that does not change the PSTN net, by having the communication equipment of FXO interface, connects the PBX (PBX) of PSTN, and the realization IP network is connected with the PSTN network.Before the FXO interface uses, system initialization FXO interface: FXO interface off-hook is set; The FXO interface detects whether there is the outside line loop current, and when detecting the FXO interface and have the outside line loop current, it is available the on-hook of FXO interface being set and FXO interface external line state is set; When detecting the FXO interface and do not have the outside line loop current, it is unavailable keeping FXO interface off-hook and FXO interface external line state is set.FXO interface off-hook is set just is used for FXO interface outside line detection, do not enter this FXO interface voice communication apparatus call flow.After initialization FXO interface is finished, for the disabled FXO interface of external line state, the FXO interface software adopts automatic regular polling to detect, keep FXO interface off-hook and regularly detect external line state from being not applicable to available variation, the FXO interface software also adopts interrupt mode to detect: interrupted to forming the loop current generation by FXO interface outside line loop free electric current.Detect the loop current of outside line when the FXO interface after, the on-hook of FXO interface, obtain the result that the outside line of FXO interface can be used, whole process is in the Millisecond time range, being no more than PBX is that the jitter elimination that user's off-hook and on-hook action are done is handled, so the off-hook of this FXO interface can not discerned by PBX to the process of on-hook.

The FXO interface detects the outside line of FXO interface when unavailable, and FXO interface voice communication apparatus can not allow the FXO interface enter call flow, and the FXO interface keeps off-hook can not influence this FXO interface outside line voice communication apparatus.

But the FXO interface detects the FXO interface outside line time spent, after the FXO of normal condition interface outside line damage or unexpected the disconnection, owing to can not form loop current, so only need the PBX of FXO interface call FXO interface outside line connection, it is unavailable just can to detect the outside line of FXO interface.FXO interface External Call PBX, FXO interface off-hook, FXO interface detect FXO interface outside line loop current and do not exist, and the FXO interface keeps off-hook, and promptly FXO interface outside line testing result is that the outside line of FXO interface is unavailable.

But the FXO interface detects the FXO interface outside line time spent, in the conversation of FXO interface, the FXO interface is in off hook state, if this time outside line disconnects, loop current disappears, it is unavailable that the FXO interface can detect the outside line of FXO interface, and in this process, the outside line of FXO interface detects can not influence any call flow.Concrete implementing procedure figure of the present invention as shown in Figure 2.

Every FXO interface voice communication apparatus possesses a FXO interface at least, and this interface quantity does not limit.The outer line detecting method of FXO interface of the present invention may be used on possessing the voice communication apparatus of a plurality of FXO interfaces.

Claims (2)

1. external line state detection method for external switching center may further comprise the steps:

A. during initialization FXO interface, FXO interface off-hook is set;

The b.FXO interface detects whether there is the outside line loop current, and when detecting the FXO interface and have the outside line loop current, it is available the on-hook of FXO interface being set and FXO interface external line state is set; When detecting the FXO interface and do not have the outside line loop current, it is unavailable keeping FXO interface off-hook and FXO interface external line state is set.

2. external line state detection method for external switching center according to claim 1 is characterized in that, also comprises the steps:

C. for the disabled FXO interface of external line state, the FXO interface regularly detects whether there is the outside line loop current, and when detecting the FXO interface and have the outside line loop current, it is available the on-hook of FXO interface being set and FXO interface external line state is set;

D. the FXO interface that can use for external line state, from FXO interface External Call PBX the time, the FXO interface detects whether there is the outside line loop current, when detecting the FXO interface and do not have the outside line loop current, it is unavailable that FXO interface external line state is set, and returns step c; Perhaps, in normal talking, the FXO interface regularly detects whether there is the outside line loop current, and when detecting the FXO interface and do not have the outside line loop current, it is unavailable that FXO interface external line state is set, and returns step c.

Images