Comrex Access NX, Руководство по эксплуатации продукта

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Maximum Delay - CrossLock operates by choosing a “ Target Delay ” figure based on jitter performance of its
various networks over a time window. To prevent excessive delay in the case of one extremely laggy network, it
has a maximum delay setting here. In the case of multiple networks with very high jitter figures, this setting can be
increased from the default five seconds by the user.
FEC - CrossLock has a powerful Forward Error Correction algorithm that is enabled in the presence of multiple
networks, using any excess network bandwidth to add in the parity required. Use of FEC is recommended, but it can
be disabled here.
FEC Delay - Controls both how much delay is introduced into the system by FEC , and also to an extent how effective
the recovery is (which is dependent greatly on the packet rate). The default of 100mS should only be altered on
recommendation of Comrex support.
Retransmit - In addition to FEC, CrossLock utilizes an ARQ style algorithm to allow retransmission of lost packets
when time permits. This mode is recommended but can be disabled here.
Retransmit Delay - CrossLock automatically provides an extra “Retransmit Cushion” that provides some time to
make ARQ error correction effective. The default amount of time is twice the measured round trip delay of the
network (2xRTT). This has been shown to be most effective on most networks, but can be altered lower (1xRTT,
none) or higher (3xRTT) using this menu.
Header Compression - The nature of Internet packets sometimes results in IP overhead (RTP headers and other
info) actually using nearly as much bandwidth as the payload. CrossLock , by default, compresses some of these
headers to conserve network bandwidth. In instances where the network rejects this, or packet inspection is
required, this compression can be disabled.