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Milan Technology MIL-S3580 User Manual

Page 23

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x Ingress Filtering examines the tagged header of each tagged frame that

enters a port and determines whether the tagged frame and the port that

received the frame are members of the same VLAN. If they belong to the same

VLAN, the port accepts the frame. If they belong to different VLANs, the port

discards the frame. If Ingress filtering is disabled, any tagged frame is

accepted on any port on the switch. It does not matter whether the frame and

port belong to the same or different VLANs.

x Per-Port Priority allows port-based priorities. You can designate the priority

for the receiving port so that any frame received will be transmitted to the

destination port with the programmed priority. However, if the received frame

has a layer 3 priority (TOS or DiffServ), it will have precedence over

port-based priority. When set, all ports by default have the lowest priority

possible. If a priority different from lowest is wanted, the priority must be

changed for each individual port in the Port Configuration Menu.

x HOLB Prevention - Head Of Line Blocking occurs when many ports send

frames to the same output port. This puts the frames in contention for output

port and all frames must wait behind, thus the head of the line goes first. The

shared memory switching fabric architecture eliminates any possibility of

head-of-line blocking when this feature is enabled.

x When QoS is enabled, you can map the Type of Service of your choice

(according to IEEE 802.1p) to the 4 priority levels provided.

x There are 3 different modes of VLANs supported in this switch, 802.1Q,

Port-Based VLANs and MTU/MDU. The choice you make here will

ultimately decide the VLAN mode and function for the entire switch. If one

mode is selected, the other two VLAN modes will have no effect on the

switch.

x GVRP Enable State is used with IEEE 802.1Q VLANs. GVRP enables the

switch to dynamically create 802.1Q compliant VLAN links with other

switches running GVRP. This reduces the chance for errors in VLAN

configuration by automatically providing VLAN ID (VID) consistency across

the network. You can use GVRP to propagate VLANs to other GVRP

switches instead of manually having to set up VLANs in each switch. In order

to activate GVRP without overlapping VLANs, follow these steps:

1. Assign

static

VLANs.

2. Take out ports that belong to assigned VLANs from Default VLAN.

3. Assign those ports to Local VID in Switch Port Configuration Menu.

4. Tag the uplink port in the Untagged Configuration Menu.

5. Turn on STP in Switch Configuration Menu.