Understanding The Switch Features; Cable Diagnostics; Poe Rule; Qos - D-Link DGS-1008P User Manual

3 Understanding The Switch Features

3
Understanding The Switch Features

Cable Diagnostics

DGS-1008P will scan all ports when device booting up. The diagnosis results will be displayed by port LED
at the first 1 second after port scan finished. And following are the explanation of the result:
Solid Green: A Gigabit connection is detected and the cable is good.
Solid Amber: No connection, bad cable or 10/100M connection is detected.
The quality of cables will impact the diagnosis results. A Gigabit connection may lower to 10/100M due to
wrong or bad quality Ethernet cables. Twisted pair Cat 5, 5e or better cable is required for Gigabit Ethernet.

PoE Rule

DGS-1008P supports many PoE features to guarantee the safety and stability of PoE power supply.
PoE Power Budget: DGS-1008P has set a limitation of maximum PoE power supply at 52 Watts to protect
the Switch and to stabilize the power transmitting to the PoE devices.
Priority: DGS-1008P has pre-defined the PoE priority for PoE ports to prevent unexpected overloading
situation from happening. Lower port numbers have higher priorities for power feeding. (Port 1 > Port 2 >
Port 3 > Port 4). When PoE overload is detected, the power supply of higher port numbers will be cut off first.
Guard Band: DGS-1008P has reserved a 7 watts Guard Band to prevent the power supply from exceeding
the PoE Power Budget. When the Switch detects the current PoE output has reached 45 watts, the Power
Max LED will light up and the Switch will check the priority of each PoE port. In the mean time, if a new PoE
device is connected, the Switch will cut off the power of the port with higher port number.
For example: When Port 2~4 are all feeding 15.4 watts power to the clients (total PoE power used = 46.2
watts), and a new PoE device is connected to port 1, the power of port 4 will be cut off.

QoS

DGS-1008P supports 4 levels of transmission queue that guarantees the important traffic will always be
transmitted first. The Switch will check the priority tags in the packets and map them into corresponding
queue levels. Below are the mapping rules:
For DSCP tag:
DSCP value 0-15 map to Queue 0 (Lowest priority queue)
DSCP value 16-31 map to Queue 1
DSCP value 32-47 map to Queue 2
DSCP value 48-63 map to Queue 3 (Highest priority queue)
For 802.1p tag:
Priority value 1 and 2 map to Queue 0 (Lowest priority queue)
No 802.1p tag or priority value 3 map to Queue 1
Priority value 4 and 5 map to Queue 2
Priority value 6 and 7 map to Queue 3 (Highest priority queue)
If a packet has both DSCP and 802.1p tags, the DSCP tag will be mapped.

Power Saving

DGS-1008P supports 2 power saving modes of Ethernet ports. The switch ports will auto detect the status of
the link and activate the power saving function automatically.
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