Quanta Cloud Technology QuantaMesh QNOS5, Руководство по настройке

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Flow control enables lower speed switches to communicate with higher speed switches by requesting that
the higher speed switch refrains from sending packets. Transmissions are temporarily halted to prevent
buffer overflows.
1.1.13. Asymmetric Flow Control
When in asymmetric flow control mode, the switch responds to PAUSE frames received from peers by
stopping packet transmission, but the switch does not initiate MAC control PAUSE frames.
When the switch is configured in asymmetric flow control (or no flow control mode), the device is placed in
egress drop mode. Egress drop mode maximizes the throughput of the system at the expense of packet loss
in a heavily congested system, and this mode avoids head of line blocking.
Asymmetric flow control is NOT supported on Fast Ethernet platforms as the support was introduced to the
physical layer with the Gigabit PHY specifications.
1.1.14. Alternate Store and Forward (ASF)
The Alternate Store and Forward (ASF) feature, which is also known as cut-through mode, reduces latency
for large packets. When ASF is enabled, the memory management unit (MMU) can forward a packet to the
egress port before it has been entirely received on the Cell Buffer Pool (CBP) memory.
1.1.15. Jumbo Frames Support
Jumbo frames enable transporting data in fewer frames to ensure less overhead, lower processing time,
and fewer interrupts. The maximum transmission unit (MTU) size is configurable per-port.
1.1.16. Auto-MDI/MDIX Support
Your switch supports auto-detection between crossed and straight-through cables. Media-Dependent
Interface (MDI) is the standard wiring for end stations, and the standard wiring for hubs and switches is
known as Media- Dependent Interface with Crossover (MDIX).
1.1.17. Unidirectional Link Detection (UDLD)
The UDLD feature detects unidirectional links physical ports by exchanging packets containing information
about neighboring devices. The purpose of the UDLD feature is to detect and avoid unidirectional links. A
unidirectional link is a forwarding anomaly in a Layer 2 communication channel in which a bidirectional link
stops passing traffic in one direction.
1.1.18. Expandable Port Configuration
Note: The manually-configured local clock settings are not retained across a system reset if the
platform does not include a Real Time Clock (RTC).