NEC Aspila EX Hardware Manual page 165

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Gatekeeper
Whenever an H.323 terminal activates, a check is made of the network to see if there are any gatekeep-
ers available. When a gatekeeper is present, it provides users with:
• Address Translation
Users typically do not know the IP addresses of other terminals. When a user makes a call, the
gatekeeper translates an alias address (name or number) to the destination address.
• Admissions Control
Users will not all be able to access the network at the same time because of limited shared
resources. Gatekeepers may restrict network access based on call authorization, bandwidth usage,
or some other criteria. It is important to note that Admissions Control is a way to preserve the
integrity of the calls (provide QoS guarantees) that are already up and operating when a user
requests access.
• Bandwidth Control
Besides network access control, the gatekeeper offers network managers the ability to restrict or
assign bandwidth to different applications along certain protocol conventions. This is another
place network managers can enforce QoS guarantees and other enterprise-wide usage policies.
With the Aspila EX system, a separate external gatekeeper is not required unless connecting to an out-
side H.323 endpoint/gateway which requires an outer gatekeeper or if over 50 outer addresses must be
registered. Otherwise, the Aspila EX provides tables within the system programming for address reso-
lution.
IP Hardware
PCBs:
• NTCPU - Signals the gateway with VoIP communication
• 16VOIPU - VoIP PCB provides a 16-channel voice packet gateway unit and works as a media
gateway for VoIP communication. This PCB is required for either VoIP trunks or when using
VoIP system phones.
• 16VOIPDB - VoIP daughter board provides an additional 16 channels when attached to the
16VOIPU PCB
• 8SHUBU - Provides an 8-port switching hub for use with the Aspila EX system
Terminals:
• IP System Phone - Aspila EX 34-button multi-line IP phone
• IP Adapter - IP adapter connects an Aspila EX system phone to the VoIP network
• ITR-2D-1 - Uniden IP phone
Power must be supplied to the IP system phone or the Legacy IP system phone using either a local or
central power supply. The ITR-2D1 phone requires local power. If there is a power outage, the VoIP
phones will not work unless the phones are plugged into a UPS (uninterruptible power supply).
• Local Power Supply
The AC-R Unit is an AC adapter for Aspila EX IP system phone or the Legacy IP system phone.
The ITR-2D1 has an AC adapter included that should be used for power. Terminals connected to
the 8SHUBU PCB must provide local power.
• Central Power Supply:
An IEEE 802.3AF Standard Power Supply or Patch Panel
Aspila EX Hardware Manual
Chuyên phân phối tổng đài NEC
The phone with the adapter installed is referred to as the Legacy IP System Phone or
DtermIP phone.
Section 6: LAN Connection
Section 6: LAN Connection
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