RuggedCom WiN51 Series, Руководство пользователя и инструкция по установке

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WiN5200 Product Description | 23
2.6.3 Default Service Flows
Default UL/DL service flows are created automatically for each registered subscriber.
These service flows are used to pass all traffic not matching any user-defined service flow
(such as broadcast ARP) between the base station and subscribers. The default service flow
capacity is limited for each subscriber.
2.6.4 Scheduling
The base station enforces QoS settings for each service flow by controlling all uplink and
downlink traffic scheduling. This provides non-contention based traffic model with
predictable transmission characteristics. By analyzing the total of requests of all subscribers,
the base station ensures that uplink and downlink traffic conforms to the current service level
agreements (SLAs). Centralized scheduling increases predictability of traffic, eliminates
contention, and provides the maximum opportunity for reducing overhead.
A regular period is scheduled for subscribers to register with the base station. These
subscribers may be newly commissioned or have been deregistered due to service outage or
interference on the wireless interface. This is the only opportunity for multiple subscribers to
transmit simultaneously.
Real-Time Polling Service (rt-PS)
The base station schedules a continuous regular series of transmit opportunities for the
subscriber to send variable size data packets. The grant size is based on the current data
transfer requirement. Typical applications include streaming MPEG video or VOIP with
silence suppression. This is efficient for applications that have a real-time component and
continuously changing bandwidth requirements.
Extended Real-Time Polling Service (ert-PS)
The base station schedules a continuous series of transmit opportunities for the subscriber to
send variable size data packets. This schedule supports real-time applications including VoIP
with silence suppression. The dynamically scheduled grants guarantee reserved bandwidth
and reduce latency introduced by repetitive grant requests. The service flow will not transmit
packets larger than nominal grant interval.
Non-Real-Time Polling Service (nrt-PS)
The base station schedules regular transmit opportunities for the subscriber to send variable
size data packets. Typical applications may include high bandwidth FTP. The polling period
may typically be one second or less, even during periods of network congestion.