HP Survivable Branch Communication zl Module powered by Microsoft Lync Planning and Design Guide 2011-02

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SBM Overview

SBM PSTN Capabilities

The HP Media Gateway is the PSTN gateway installed on the SBM. The Media

Gateway acts as the branch site’s interface between the Microsoft UC&C

solution and the PSTN.

The gateway supports these technologies:

■ SIP for communicating with the Microsoft solution

■ These technologies for communicating on the PSTN:

• ISDN Primary Rate Interface (PRI) on digital T1/E1 interfaces

• Analog on Foreign Exchange Office (FXO) interfaces and Foreign

Exchange Subscriber (FXS) interfaces

The ISDN lines also offer features such as:

■ Echo cancellation

■ Comfort noise

■ Configurable hunt settings (the strategy that the interface uses to assign

calls to channels)

ISDN

ISDN is a standard for transmitting network services, including voice, data,

and video, over traditional PSTN wires.

T1 and E1

T1 and E1 are ISDN’s most common PRI standards. They use time-division

multiplexing to carry multiple transmission channels on a single physical

connection. T1 features a 1.54 Mbps connection, which includes 24 channels

at 64 Kbps each and 8 Kbps for framing information. E1 features a 2.048 Mbps

connection, which includes 32 channels at 64 Kbps each. One channel is

typically used for signalling information and another for framing information,

so E1 provides 30 transmission channels.

The SBM’s T1 and E1 connections are used for voice transmissions.