Samsung Ubigate iBG3026, Руководство по настройке

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Ubigate iBG3026 Configuration Guide/Ed.00
© SAMSUNG Electronics Co., Ltd.
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One of the defects is that there is no way to notify users of far-end
disconnect or answer, making users impossible to know about the status.
In the case of loop-start signaling, FXS only uses the A-bit and the FXO
side only uses the B-bit to communicate call information..
2.
Groundstart signaling
Is very similar with loop-start signaling in many ways.
Its merits compared with loop-start signaling are its supporting far-end
disconnect supervision loop-start does not provide. This is done by using the
A- and B- bit on the network side instead of just the B-bit. The A-bit is also
used on the CPE side. However, the B-bit can also be involved, based on the
switch’s implementation.
Provides emulated-OPX from a PBX to remote stations using FXS and
FXO connection. When FXS interworks with FXO, FXO and FXS should
be directly connected between switches. When FXS connects to FXO,
signaling should be matched using either ground-start or loop-start signaling.
FXO provides better disconnect supervision than FXS. In this case,
disconnect supervision means the function to notice the fact that other party
hung up call. Ground start provides this function, but connection should be
formed after understanding the characters of PBX due to the fact that all the
PBXs do not possess FXS/FXO port supporting ground-start.
3.
Groundstart signaling
Generally used for trunk lines. Because it is the signaling type devised to
complement defects of FXS/FXO, E & M connection is preferable to
FXS/FXO. E & M connections from routers to telephone switches or to
PBXs provide better answer and disconnect supervision.
E & M signaling has many advantages over the previous CAS signaling
methods discussed in this document. It provides both disconnect and answer
supervision as well as glare avoidance. E & M signaling is simple to
understand and is the preferred choice when you use CAS.