Lost Packet Recovery And Dynamic Bandwidth; Configure The System For Use With A Firewall Or Nat - Polycom realpresence group series Administrator's Manual

Setting
Maximum Transmission
Unit Size Bytes
Enable Lost Packet
Recovery
Enable RSVP
Dynamic Bandwidth
MRC Bandwidth
Allocation
Maximum Transmit
Bandwidth
Maximum Receive
Bandwidth
Note: When a RealPresence Group 500 or RealPresence Group 700 system is hosting a multipoint call, the total
call rate for all sites in the call is 6 Mbps.

Lost Packet Recovery and Dynamic Bandwidth

You can handle video quality issues by selecting the Enable Lost Packet Recovery (LPR) setting, the
Dynamic Bandwidth setting, or both settings.
If both settings are enabled, Dynamic Bandwidth adjusts the video rate to reduce packet loss to 3% or less.
When packet loss drops to 3% or less, LPR cleans up the video image on your monitor. The additional
processing power required might cause the video rate to drop while the system is using LPR. If this
happens, the Call Statistics screen shows the Video Rate Used as lower than the Video Rate. If Packet Loss
is 0 for at least 10 minutes, LPR stops operating and the Video Rate Used increases to match the Video
Rate.
If only LPR is enabled and the system detects packet loss, LPR attempts to clean the image but the video
rate is not adjusted. If only Dynamic Bandwidth is enabled and the system detects packet loss of 3% or
more, the video rate is adjusted but LPR does not clean the image.
You can view % Packet Loss, Video Rate, and Video Rate Used on the Call Statistics screen.

Configure the System for Use with a Firewall or NAT

A firewall protects an organization's IP network by controlling data traffic from outside the network. Unless
the firewall is designed to work with H.323 video conferencing equipment, you must configure the system
and the firewall to allow video conferencing traffic to pass in and out of the network.
Polycom, Inc.
Description
Specifies the MTU size, in bytes, used in IP calls. If the video becomes blocky or
network errors occur, packets might be too large; decrease the MTU. If the network
is burdened with unnecessary overhead, packets might be too small; increase the
MTU.
Allows the system to use LPR (Lost Packet Recovery) if packet loss occurs.
Allows the system to use Resource Reservation Setup Protocol (RSVP) to request
that routers reserve bandwidth along an IP connection path. Both the near site and
far site must support RSVP in order for reservation requests to be made to routers
on the connection path.
Specifies whether to let the system automatically find the optimum call rate for a call.
Adjusts media bit stream bandwidth, reducing packet loss. Specifically designed for
SVC-based calls. For more information on SVC, see
Specifies the maximum transmit call rate between 64 kbps and the system's
maximum line rate. This setting can be useful when the system is connected to the
network using an access technology that provides different transmit and receive
bandwidth (such as cable or DSL access).
Specifies the maximum receive call rate between 64 kbps and the system's
maximum line rate. This setting can be useful when the system is connected to the
network using an access technology that provides different transmit and receive
bandwidth (such as cable or DSL access).
Networks
Set SVC Call Preferences.
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