Dell PowerConnect 3548 User Manual

66 Configuring PowerConnect 3524/P and 3548/P
Port Default Settings
The general information for configuring the device ports includes the short description of the
auto-negotiation mechanism and the default settings for switching ports.
Auto-Negotiation
Auto-negotiation enables automatic detection of speed, duplex mode and flow control on all switching
10/100/1000BaseT ports. Auto-negotiation is enabled per port by default.
Auto-negotiation is a mechanism established between two link partners to enable a port to advertise its
transmission rate, duplex mode and flow control (the flow control default is disabled) abilities to its
partner. The ports then both operate at the highest common denominator between them.
If connecting a NIC that does not support auto-negotiation or is not set to auto-negotiation, both the
device switching port and the NIC must be manually set to the same speed and duplex mode.
If the station on the other side of the link attempts to auto-negotiate with a device 100BaseT port that is
configured to full duplex, the auto-negotiation results in the station attempting to operate in half duplex.
MDI/MDIX
The device supports auto-detection of straight through and crossed cables on all switching
10/100/1000BaseT ports. The feature is part of the Auto-negotiation and is enabled when
Auto-negotiation is enabled.
When the MDI/MDIX (Media Dependent Interface with Crossover) is enabled, the automatic
correction of errors in cable selection is possible, thus making the distinction between a straight
through cable and a crossover cable irrelevant. (The standard wiring for end stations is known as MDI
(Media Dependent Interface), and the standard wiring for hubs and switches is known as MDIX.
Flow Control
The device supports 802.3x Flow Control for ports configured with the Full Duplex mode. By default,
this feature is disabled. It can be enabled per port. The flow control mechanism allows the receiving side
to signal to the transmitting side that transmission must temporarily be halted to prevent buffer
overflow.
Back Pressure
The device supports back pressure for ports configured with the half duplex mode. By default, this
feature is disabled. It can be enabled per port. The back-pressure mechanism prevents the sender from
transmitting additional traffic temporarily. The receiver may occupy a link so it becomes unavailable for
additional traffic.

Dell PowerConnect 3548 Specifications

General

MAC address table	8000 entries
Maximum data transfer rate	0.1 Gbit/s
Supported data transfer rates	10/100 Mbps
10G support	-
Number of VLANs	256
Flow control support	Yes
Networking standards	IEEE 802.1D, IEEE 802.1p, IEEE 802.1Q, IEEE 802.1s, IEEE 802.1w, IEEE 802.3ad
Dimensions (WxDxH)	440 x 257 x 43.2 mm
Networking features	Gigabit Ethernet, Fast Ethernet
Authentication method	RADIUS, TACACS+
Connectivity technology	Wired
Switch type	Managed
Switch layer	L2
Data link protocols	Ethernet
Supported network protocols	HTTP, HTTPS/SSL, SSH
Power connector	DC-in jack
SFP/SFP+ slots quantity	2
Basic switching RJ-45 Ethernet ports quantity	48
Product color	Black
Storage temperature (T-T)	-20 - 70 °C
Operating temperature (T-T)	0 - 45 °C
Storage relative humidity (H-H)	10 - 95 %
Operating relative humidity (H-H)	10 - 90 %

Weight and Dimensions

Weight	8000 g