LL
AA
NN
SS
ww
ii
tt
cc
hh
ee
ss
5
VLANs
VLANs allow PCs, workstations, and
other resources, including printers and
file servers, to be organized into logical,
broadcast domains so that only devices
within the same domain can commu-
nicate with each other. 3Com switches
allow users to implement VLANs on
their network using one of two schemes:
IEEE 802.1Q, including GVRP, which
enables the auto-learning of VLANs, or
3Com’s VLT. Both methods allow for the
configuration of VLANs based on ports
and/or MAC addresses for maximum
flexibility and security. For 802.1Q
VLANs, a port on a switch can be
assigned to a VLAN; all other switches
learn about that VLAN when the
switches automatically communicate that
knowledge via the GVRP protocol.
Switches supporting both VLAN
schemes can be used to provide seamless
migration from VLT to IEEE 802.1Q
environments that preserve investment
in current LAN developments and
equipment.
Layer 3 Support
Multicast filtering using IGMP
snooping
Multicast filtering enables the automatic
configuration of filters for IP multicast
traffic, such as video and audio broad-
casts, allowing advanced multimedia
applications to be delivered easily to the
workgroup.
Fast IP
Fast IP is 3Com’s standards-based cut-
through routing solution for all types
of legacy routing network backbones.
This reduces traffic flow through router
bottlenecks and maximizes performance
by utilizing the switched infrastructure.
Layer 3 switching
Layer 3 switching is the implementation
of routing protocols in leading-edge
ASIC technology. Routing performance
is dramatically and cost effectively
boosted to enable the widespread
deployment of intranets (IP-based
networking).
automatically enable a second port
buffer for high-priority traffic thereby
allowing the traffic to bypass lower pri-
ority data for faster processing within
the switch.
Traffic Management
Flow control
Flow control is an essential switch
feature that eliminates dropped packets
on congested ports. To provide switch
application flexibility, 3Com switches
support flow control schemes suited to
both full- and half-duplex environments.
Intelligent Flow Management (IFM)
is a solution designed to work in half
duplex, for example, a hub aggregation
application. A solution using IEEE
802.3x is also supported and designed
for full-duplex connections, such as
desktop switching; this method of flow
control is set automatically using the
autosensing features of SuperStack II
switches.
Broadcast traffic control
Traditional Ethernet switches suffer from
the threat of broadcast storms that can
potentially bring networks to a halt.
However, all SuperStack II switches
can be configured with broadcast storm
protection to limit the number of
broadcast packets allowed to be
forwarded by each port. This allows the
SuperStack II switches to offer the
security of broadcast storm protection
normally associated with a router while
also providing the protocol independence
of a switch.
Network Availability
Backup power supplies
3Com gives you all the choices you
need to ensure constant power to your
stackable switches. Both the Advanced
Redundant Power System (ARPS) and
the Uninterruptible Power System
(UPS) work with any SuperStack II
switch. The ARPS is ideally suited as a
backup for individual power supplies in
the SuperStack II units. The UPS fully
protects your SuperStack II system
from the effects of brownouts or spikes
that occur in outside power lines.
Resilient links
3Com’s simple and flexible resilient
links technology ensures fault tolerance
via redundant connections to other
network devices.
Spanning tree
Support for the industry-standard
IEEE 802.1D spanning tree protocol is
provided as an alternative to resilient
links. This protects against network
loops and can be used to provide
redundant network paths.
Port trunking
Port trunking establishes backbone
links by treating multiple parallel links
as a single network pipe. Trunking also
provides link redundancy; traffic on
any failed link comprising a network
trunk automatically switches over to
the other links in the trunk.
Resilient links
UPS backup po
w
er
supplies
VL
AN
(IE
EE
802.1Q )
Spanning tr
ee
Br
oadcast tr
affic contr
ol
Intelligent
switching mode
Lay
er 3 switching
Trunking
Fast I
P
Multicast filtering using
IGM
P
snooping
Fu
ll duplex on all
por
ts
l-I
FM
VL
AN
(VL
T)
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
■
●
●
●
●
●
●
●
●
●
●
●
■
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
■
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
●
AR
PS/Type 2 backup
po
w
er supplies