3Com 1000 User Manual
Page 54
4-10
C
HAPTER
4: M
ANAGING
T
HE
S
WITCH
1000
PACE Enable / Disable This field allows you to
enable or disable PACE (Priority Access Control
Enabled) for all ports on the Switch. PACE allows
multimedia traffic to be carried over standard Ether-
net and Fast Ethernet LANs by providing two fea-
tures:
■
Implicit Class of Service — When multimedia traf-
fic is transmitted, it is given a higher priority
than other data and is therefore forwarded ahead
of other data when it arrives at the Switch. The
Implicit Class of Service feature minimizes latency
through the Switch and protects the quality of
multimedia traffic.
■
Interactive Access — When two-way multimedia
traffic passes over an Ethernet network, interfer-
ence can occur because access to the bandwidth
is unequally allocated to traffic in one direction.
The Interactive Access feature allocates the avail-
able bandwidth equally in both directions, there-
fore increasing the quality of the traffic.
Interactive Access should only be enabled on ports
that connect to a single endstation, switch, bridge
or router. You should disable Interactive Access on
a port if it is connected to a repeater. Also, Interac-
tive Access should only be enabled at one end of
the link.
For more information about disabling Interactive
Access for a port, refer to
VLAN Configuration Mode Port / AutoSelect This
field allows you to specify how ports on the Switch
are placed in VLANs:
■
Port — The ports use Port VLAN Mode, which
means that they are manually placed in the
required VLAN. This is the default mode.
■
AutoSelect — The ports use AutoSelect VLAN
Mode, which means that they are automatically
placed in the required VLAN by referring to a
VLAN Server database in 3Com’s Transcend
®
Enterprise Manager software.
For more information, refer to
Bridging Mode Forward To All / Forward To Back-
bone This field allows you to set the bridging mode,
which controls how packets with unknown
addresses are processed:
■
Forward To All — The Switch forwards packets
with an unknown address to all ports in the same
VLAN as the source port. This setting should
only be used if your network has less than 500
MAC addresses.
■
Forward To Backbone — The Switch forwards
packets with an unknown address to the back-
bone port defined for the VLAN of the source
port. This is the default setting.
For more information about VLANs and backbone
ports, refer to
on