Chapter 8 Basic Setting
GS1920 Series User’s Guide
69
8.8
PoE Status
Note:
The following screens are available for the PoE model(s) only. Some features are
only available for the Ethernet ports (1 to 24 for GS1920-24HP and 1 to 48 for
GS1920-48HP).
The PoE model(s) supports the IEEE 802.3at High Power over Ethernet (PoE) standard.
A powered device (PD) is a device such as an access point or a switch, that supports PoE (Power
over Ethernet) so that it can receive power from another device through an Ethernet port.
In the figure below, the IP camera and IP phone get their power directly from the Switch. Aside
from minimizing the need for cables and wires, PoE removes the hassle of trying to find a nearby
electric outlet to power up devices.
Figure 51
Powered Device Examples
You can also set priorities so that the Switch is able to reserve and allocate power to certain PDs.
Note:
The POE (Power over Ethernet) devices that supply or receive power and their
connected Ethernet cables must all be completely indoors.
Flow Control
A concentration of traffic on a port decreases port bandwidth and overflows buffer memory
causing packet discards and frame losses. Flow Control is used to regulate transmission of
signals to match the bandwidth of the receiving port.
The Switch uses IEEE802.3x flow control in full duplex mode and backpressure flow control in
half duplex mode.
IEEE802.3x flow control is used in full duplex mode to send a pause signal to the sending
port, causing it to temporarily stop sending signals when the receiving port memory buffers
fill.
Back Pressure flow control is typically used in half duplex mode to send a "collision" signal to
the sending port (mimicking a state of packet collision) causing the sending port to
temporarily stop sending signals and resend later. Select Flow Control to enable it.
802.1p
Priority
This priority value is added to incoming frames without a (802.1p) priority queue tag.
See
Priority Queue Assignment in Table 12 on page 64 for more information.
Apply
Click Apply to save your changes to the Switch’s run-time memory. The Switch loses these
changes if it is turned off or loses power, so use the Save link on the top navigation panel to
save your changes to the non-volatile memory when you are done configuring.
Cancel
Click Cancel to begin configuring this screen afresh.
Table 14
Basic Setting > Port Setup (continued)
LABEL
DESCRIPTION
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
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378
379
380
381
