Edge-Core ECS4810-12M Layer 2, Management Manual, Page: 58 / 1236

C
HAPTER
1
| Introduction
Description of Software Features
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broadcast traffic passing through the port is restricted. If broadcast traffic
rises above a pre-defined threshold, it will be throttled until the level falls
back beneath the threshold.
S
TATIC
A
DDRESSES
A static address can be assigned to a specific interface on this switch.
Static addresses are bound to the assigned interface and will not be
moved. When a static address is seen on another interface, the address will
be ignored and will not be written to the address table. Static addresses
can be used to provide network security by restricting access for a known
host to a specific port.
IP A
DDRESS
F
ILTERING
Access to insecure ports can be controlled using DHCP Snooping which
filters ingress traffic based on static IP addresses and addresses stored in
the DHCP Snooping table. Traffic can also be restricted to specific source IP
addresses or source IP/MAC address pairs based on static entries or entries
stored in the DHCP Snooping table.
IEEE 802.1D B
RIDGE
The switch supports IEEE 802.1D transparent bridging. The address table
facilitates data switching by learning addresses, and then filtering or
forwarding traffic based on this information. The address table supports up
to 16K addresses.
S
TORE
-
AND
-F
ORWARD
S
WITCHING
The switch copies each frame into its memory before forwarding them to
another port. This ensures that all frames are a standard Ethernet size and
have been verified for accuracy with the cyclic redundancy check (CRC).
This prevents bad frames from entering the network and wasting
bandwidth.
To avoid dropping frames on congested ports, the switch provides 4 Mbits
for frame buffering. This buffer can queue packets awaiting transmission
on congested networks.
S
PANNING
T
REE
A
LGORITHM
The switch supports these spanning tree protocols:
◆ Spanning Tree Protocol (STP, IEEE 802.1D) – This protocol provides
loop detection. When there are multiple physical paths between
segments, this protocol will choose a single path and disable all others
to ensure that only one route exists between any two stations on the
network. This prevents the creation of network loops. However, if the
chosen path should fail for any reason, an alternate path will be
activated to maintain the connection.
◆ Rapid Spanning Tree Protocol (RSTP, IEEE 802.1w) – This protocol
reduces the convergence time for network topology changes to about 3
to 5 seconds, compared to 30 seconds or more for the older IEEE
802.1D STP standard. It is intended as a complete replacement for STP,
but can still interoperate with switches running the older standard by