Optimization; Ethernet Switch; Application Network Setup; Real-Time Transport Protocol Ports - Polycom SoundPoint IP 300 Administrator's Manual

Administrator's Guide - SoundPoint

4 Optimization

4.1 Ethernet Switch

The SoundPoint
embedded Ethernet switch that runs at full line-rate. The Ethernet switch allows a per-
sonal computer and other Ethernet devices to connect to the office LAN by daisy
chaining through the phone, eliminating the need for a stand-alone hub. The
SoundPoint
phone. SoundPoint
line-powered (power supplied through the signaling or idle pairs of the LAN Ethernet
cable). Line powering typically requires that the phone plugs directly into a dedicated
LAN jack. Devices that do not require LAN power can then plug into the
SoundPoint
SoundPoint
To help ensure good voice quality, the Ethernet switch embedded in the
SoundPoint
phone higher transmit priority than those from a device connected to the PC port. If
not using a VLAN (VLAN blank in the setup menu), this will automatically be the
case. If using a VLAN, ensure that the 802.1p priorities for both default and real-time
transport protocol (RTP) packet types are set to 2 or greater. Otherwise, these packets
will compete equally with those from the PC port. For more information, refer to
4.6.1.9 Quality of Service <QOS/> on page 118.

4.2 Application Network Setup

4.2.1 Real-Time Transport Protocol Ports

The phone is compatible with RFC 1889 - RTP: A Transport Protocol for Real-Time
Applications - and the updated RFCs 3550 and 3551. Consistent with RFC 1889, the
phone treats all RTP streams as bi-directional from a control perspective and expects
that both RTP end points will negotiate the respective destination IP addresses and
ports. This allows real-time transport control protocol (RTCP) to operate correctly
even with RTP media flowing in only a single direction, or not at all. It also allows
greater security: packets from unauthorized sources can be rejected.
® ®
IP / SoundStation
®
IP phones contain two Ethernet ports, labeled LAN and PC, and an
®
IP switch gives higher transmit priority to packets originating in the
®
IP can be powered through a local AC power adapter or can be
®
IP PC Ethernet port.
®
IP Switch - Port Priorities
®
IP phones should be configured to give voice traffic emanating from the
Copyright © 2006 Polycom, Inc.
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