Wide Area Network (Wan) Quality Of Service; Network Setup Review - Linksys SPA9000-NA Installation And Configuration Manual

NOTE:
Some ITSP SIP trunk services limit the maximum number of simultaneous calls . Please check
with your Service Provider to understand the maximum number of simultaneous calls each SIP trunk
supports .
For more information about bandwidth calculation, refer to the following web sites:
http://www .erlang .com/calculator/lipb/
http://www .packetizer .com/voip/diagnostics/bandcalc .html

Wide Area Network (WAN) Quality of Service

You can choose from several types of broadband access technologies to provide symmetric or
asymmetric connectivity to a small business . These technologies vary on the available bandwidth and
on the quality of service . It is generally recommended that you use broadband access with a Service
Level Agreement that provides quality of service . If there is not a Service Level Agreement with regard
to the broadband connection quality of service, the downstream audio quality may be affected
negatively under heavy load conditions (bandwidth utilization beyond 80%) . To eliminate or minimize
this effect, Linksys recommends one of the following actions:
For broadband connections with a bandwidth lower than 2 Mbps, perform the call capacity
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calculations by assuming a bandwidth value of 50% of the existing broadband bandwidth . For
example, in the case of a 2 Mbps uplink broadband connection, assume 1 Mbps . Limit the uplink
bandwidth in the Integrated Access Device to this value . This setting helps to maintain the
utilization levels below 60%, thus reducing jitter and packet loss .
Use an additional broadband connection for voice services only . A separate connection is required
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when the broadband connection services do not offer quality of service and when it is not
possible to apply the above mentioned utilization mechanism .

Network Setup Review

The Local Area Network (LAN) is the communication platform used by the LVS for allowing
communications among the telephone users and between the telephone users and the external
VoIP, PSTN or/and ISDN network services . This LAN is composed of the data wiring (UTP cabling),
networking equipment (switches and routers/access device) and the telecommunication (PSTN or
ISDN) lines .
The Local Area Network (LAN) may be already installed or it can be installed and configured at the
time of installing the LVS system . Below are the general recommendations for Local Area Networks
running LVS communications:
Infrastructure, Cabling and PSTN/ISDN Lines:
AC outlets: Ensure there is an AC outlet available for every LAN and LVS component that requires
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AC power . If you are using a Power over Ethernet switch, SPA9x2 phones do not require an AC
outlet as they are powered by the switch .
Ethernet cabling: Ensure there is a Ethernet cabling system and outlets setup for every LVS
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component to install . It is recommended that Ethernet cables are UTP CAT 5e or better .
PSTN and ISDN lines: Ensure that the lines are operative and that any features, such as caller
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identification, operate properly before starting the installation . Ensure that the cables are available
in the location where you are installing the LVS components .
UPS: If you are using an Uninterrupted Power Supply (UPS) mechanism, ensure that the LVS
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design is covered by the UPS by securing the router and switch AC connections, and the LVS
components, by using the Power over Ethernet adapter (POES5) for the non-POE products
(SPA9000, SPA400, SPA9x1 phones) . Also ensure that devices such as the WAN modem, CSU/DSU,
or DDS modem are connected to the UPS .
Linksys Voice System Installation and Configuration Guide
Preparation
Network Setup Review
20