Overview Of Connextions; Installation Requirements; Wan Router - 3Com SuperStack 3 NBX Administrator's Manual

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PPENDIX ONNE
Overview of
ConneXtions
Installation
Requirements

WAN Router

X H.323 G
TIONS ATEWAY
ConneXtions is a 3Com software product that allows you to use an
appropriately configured Windows system as an H.323 gateway for use
with NBX systems.
H.323 gateways implement an ITU standard that allows telephone-like
call connections to occur through an IP network. Although this standard
addresses the means for transferring data, voice, and images, the NBX
ConneXtions H.323 Gateway focuses on delivering low-cost, high-quality,
voice connections through IP networks.
The ConneXtions software adapts internal NBX system protocols to
equivalent H.323 protocols that are carried across a WAN in IP packets.
The H.323 protocol addresses:
Negotiated connections.
■
Negotiated voice compression.
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Standard extensions.
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Remote Internet device connections.
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For more information, see "Overview of H.323" later in this appendix.
The ConneXtions H.323 Gateway software requires an NBX system and
at least four additional components:
A router with access to a wide area network (WAN)
■
A Windows-based server connected to the NBX LAN
■
ConneXtions software (on the Resource Pack CD)
■
A ConneXtions license
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Systems that receive H.323 calls through the public Internet may also
need a firewall. See "Firewall Security" later in this appendix.
WAN Routers typically connect to ISDN, T1, E1, Frame Relay, or
Asynchronous Transfer Mode facilities, depending on the load they carry.
A dedicated router can often reduce problems encountered with
firewalls. Firewalls often interfere with connections because they are
designed to admit only authorized addresses, and because they
discriminate against specific types of packets. The unusual complexity of