Dell PowerEdge M420 Dell PowerConnect M8024-k User's Configuration Guide - Page 66
Switching Features, Flow Control Support (IEEE 802.3x), Head of Line Blocking Prevention
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Switching Features Flow Control Support (IEEE 802.3x) 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. For information about configuring flow control, see "Configuring Port-Based Traffic Control" on page 691. Head of Line Blocking Prevention Head of Line (HOL) blocking prevention prevents traffic delays and frame loss caused by traffic competing for the same egress port resources. HOL blocking queues packets, and the packets at the head of the queue are forwarded before packets at the end of the queue. Alternate Store and Forward (ASF) The Alternate Store and Forward (ASF) feature 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. AFS, which is also known as cut-through mode, is configurable through the command-line interface. For information about how to configure the AFS feature, see the CLI Reference Guide available at support.dell.com/manuals. Jumbo Frames Support Jumbo frames enable transporting data in fewer frames to ensure less overhead, lower processing time, and fewer interrupts. For information about configuring the port MTU, see "Configuring Port Characteristics" on page 491. 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 MediaDependent Interface with Crossover (MDIX). 66 Switch Features
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1,202
-
1,203
-
1,204
-
1,205
-
1,206
-
1,207
-
1,208
-
1,209
-
1,210
-
1,211
-
1,212
-
1,213
-
1,214
-
1,215
-
1,216
-
1,217
-
1,218
-
1,219
-
1,220
-
1,221
-
1,222
-
1,223
-
1,224
-
1,225
-
1,226
-
1,227
-
1,228
-
1,229
-
1,230
-
1,231
-
1,232
-
1,233
-
1,234
-
1,235
-
1,236
-
1,237
-
1,238
-
1,239
-
1,240
-
1,241
-
1,242
-
1,243
-
1,244
-
1,245
-
1,246