Network Requirements - NEC SL1100 Features And Specifications Manual

SL1100
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When the capacity is exceeded, an alarm report is generated and the message "NW port limit
exceeded" is displayed on an Alarm indication telephone. To restore the network, so all systems can
communicate with each other, the system totals need to be brought below the 168 port maximum.
After the necessary ports (station or trunk) are removed from a system, a restart of the SL1100 is not
required. Every time a system in an SL Net network is reset, a port count is performed. If the network
port count is below 168, all systems are allowed to communicate.
InMail ports are not counted against the 168 port maximum capacity.
Each system will require a VoIPDB, which by default will provide 16 channels to be shared for all IP
related devices (e.g. IP Phones, IP Trunks, SL Net). If more than 16 channels are required at any site,
the system must have the following license: SL-IP-CHANNEL-16 LIC (0042). With this license
installed, the system will now have 32 channels to share for all IP devices. Every system that requires
32 ports must purchase and install this license.

Network Requirements

The voice quality of VoIP depends on variables such as available bandwidth, network latency, and
quality of service initiatives (QoS), all of which are controlled by the network and internet service
providers. Because these variables are not within NEC's control, the performance of the users IP-
based voice solution cannot be guaranteed. Therefore, NEC recommends connecting the VoIP
equipment through a fully managed data network with Quality of Service (QOS) implemented.
For a network to be suitable for VoIP it must pass specific requirements. The requirements are:
• One way delay must not exceed 150 ms
• Round trip delay must not exceed 300 ms
• Packet loss must not exceed 1 %
• Data switches must be manageable
• No half-duplex equipment may be present in the network
• Routers must provide QOS
Depending upon how the QOS policies are built in the network, assignments may be needed in the CPU
(PRG 84-10).
• Adequate bandwidth for the estimated VoIP traffic must be available
See below chart for bandwidth calculations.
Below is a chart that shows the average bandwidth per VoIP call over Ethernet.
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SL Net