Nortel BayStack 5520-24T-PWR Specifications page 3

Auto discovery feature
The BayStack 5520 Switches automatically recognize the connection of a Power over
Ethernet device and immediately send power to it. This automatic capability ensures fast
connectivity without manual intervention.
Dynamic power management
Each port can be configured to limit the power delivered to a device. Each port can also be
configured for power priority level—low, high, and critical. On the switch, total available
power is monitored. In the case where all available power is fully utilized, the switch may
turn off lower priority ports and turn on higher priority ports.
Active circuit protection
The BayStack 5520 Switches can automatically disable a port if there is a short. All the other
ports on the switch will remain active and will not be affected by the disabled port.
Plug-n-play IP Telephony switching Figure 3. Recessed stack connectors
The BayStack 5520 Switches provide simplified Web-based configurations on data and
Recessed connectors
power properties. The graphical user interfaces make it simple to set up data and power
configurations.
Convenience of a single cable
With the BayStack 5520 Switches, data and power can be transmitted over
one cable without using a power outlet. There is no need for a separate
cable connecting the device to a power outlet.
Significant space and cost savings
Traditionally, a mid-span patch panel device connects via a UTP cat 5 cable
to a standard Ethernet switch and then the mid-span patch panel device sends
power over another standard UTP cat 5 cable to the device such as an IP phone
needing power. In essence, two units are needed for Power over Ethernet capability. In
contrast, a BayStack 5520 Switch integrates standard LAN switch functionality with the
power over UTP cable capability of a mid-span patch panel into one unit. This results in
significant cost and space savings.
Innovative FAST stacking design
Nortel Networks innovative FAST (Flexible Advanced Stacking Technology) stacking design
of the BayStack 5520 allows for simultaneous bi-directional traffic flow on each stacking port
(Figure 2). In a full stack, this design yields up to 640 Gbps—the highest stacking bandwidth
in the industry today.
Switch fabric architecture offering non-blocking wire-speed performance
The BayStack 5520 Switches have a high performance Layer 3 switching fabric with a
maximum of 160 Gbps forwarding bandwidth and wire-speed performance. The forwarding
rate for the BayStack 5520-48T-PWR is 71.4 Mpps (million packets per second) and for the
BayStack 5520-24T-PWR is 35.7 Mpps.
Layer 3 switching
The BayStack 5520 Switch architecture supports wire-speed Layer 3 IP switching across the
stack with static and local route support.
The BayStack 5520 switches support high-performance wire-speed IP routing between
VLANs. IP routing with static routes at the edge improves the network performance as the
packets do not have to go to the core and the routing takes place within the switch or stack.
To configure IP routing on the BayStack 5520 Switches or stack, you must use virtual LANs
(VLANs) to create IP interfaces. You can create IP interfaces by assigning an IP address to a
VLAN. Once VLANs are created, you must also create static routes between the BayStack
5520 Switches and the end device.
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