evertz 7890IXG, Руководство пользователя

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7890IXG
Internet Exchange Gateway
Page - 48
Revision 2.3
Destination UDP Port: This parameter allows the user to set the RX side IP Stream Network Destination
port number. This means the IP address that the received transport stream will be output on to the access
port.
Source UDP Port: This parameter allows the user to set the RX side IP Stream Network Source UDP port
number. This means the UDP port that the received transport stream will be output on to the access port.
Expected Jitter: This parameter allows the user to set the IP Stream Network of RX side expected jitter
for the WAN network.
ARQ
ARQ Port
: This parameter allows the user to set the RX side IP Stream ARQ port. This must match the
ARQ port on the transmitting 7890IXG or Evertz Cloudbridge.
By default, ARQ normally sends upstream
retransmission request packets on UDP port 7020. The ARQ Port setting can be changed to any valid
and non-conflicting UDP port. However, the same port number at both the encoder and the decoder
should be defined. To help bypass firewall blocking, reset this to be the same port as the media UDP
port, usually 10000.
ARQ Mode: This parameter allows the user to set the RX side IP Stream ARQ mode : Auto or Manual.
Auto will attempt to pick appropriate values based on network conditions, while manual gives the user full
control over retransmission parameters. When AUTO is set, you cannot set the number of retransmits or
the round trip latency.
Number Retransmits: This parameter allows the user to set the RX side IP Stream ARQ Manual Mode
maximum number of retransmissions when packet loss is detected. Higher values give more protection
but increase the latency.
Round Trip Latency: This parameter allows the user to set the RX side IP Stream ARQ Manual Mode
Round Trip Time, if it is known.
Target Latency: Target Latency, specifies the total delay, in milliseconds, allotted for the request,
retransmission, and recovery process. The ARQ mechanism will attempt as many retries as possible
within this target latency time. Thus, larger target latency times increase the delay before video is output,
but allows for more chances of requesting and recovering any missing packets. The ARQ error correction
operates through the addition of a small additional buffering delay to provide enough time to request and
receive replacement for each lost packet. Target Latency gives the ARQ mechanism a target value for
determining the necessary ARQ delay. The ARQ divides the Target Latency, specified in milliseconds, by
the round-trip time to the video encoding source to determine the number of request attempts. Unless
Robust Mode is enabled, it sets a minimum ARQ latency of one round-trip time. A larger Target Latency
allows the system to increase the number or repeat requests.
Max Burst Drop: A Burst Drop delay can also be specified to delay any retransmission requests for a time
equal to the maximum expected packet loss time, such as from dynamic router changes of other sources
of burst loss.
Multi-Retransmit Mode: This parameter allows the user to enable or disable RX side Proxy ARQ Auto
Mode Robust Mode. This gives high performance for stream recovery with the tradeoff of more latency.
Normally, the ARQ will only require that a minimum of one repeat request is sent to the video encoding
source device, regardless of the Target Latency. However, enabling Robust Mode will increase the
minimum number of repeat requests to a minimum of two retries.