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LevelOne GTL-2691 User Manual

Page 76

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C

HAPTER

1

| Introduction

Description of Software Features

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Simplify network management for node changes/moves by remotely

configuring VLAN membership for any port, rather than having to

manually change the network connection.

Provide data security by restricting all traffic to the originating VLAN,

except where a connection is explicitly defined via the switch's routing

service.

Use private VLANs to restrict traffic to pass only between data ports

and the uplink ports, thereby isolating adjacent ports within the same

VLAN, and allowing you to limit the total number of VLANs that need to

be configured.

Use protocol VLANs to restrict traffic to specified interfaces based on

protocol type.

IEEE 802.1Q

T

UNNELING

(Q

IN

Q)

This feature is designed for service providers carrying traffic for multiple

customers across their networks. QinQ tunneling is used to maintain

customer-specific VLAN and Layer 2 protocol configurations even when

different customers use the same internal VLAN IDs. This is accomplished

by inserting Service Provider VLAN (SPVLAN) tags into the customer’s

frames when they enter the service provider’s network, and then stripping

the tags when the frames leave the network.

T

RAFFIC

P

RIORITIZATION

This switch prioritizes each packet based on the required level of service,

using eight priority queues with strict priority, Weighted Round Robin

(WRR), or a combination of strict and weighted queuing. It uses IEEE

802.1p and 802.1Q tags to prioritize incoming traffic based on input from

the end-station application. These functions can be used to provide

independent priorities for delay-sensitive data and best-effort data.

This switch also supports several common methods of prioritizing layer 3/4

traffic to meet application requirements. Traffic can be prioritized based on

the priority bits in the IP frame’s Type of Service (ToS) octet using DSCP, IP

Precedence, or TCP/UDP port numbers. When these services are enabled,

the priorities are mapped to a Class of Service value by the switch, and the

traffic then sent to the corresponding output queue.

Q

UALITY

OF

S

ERVICE

Differentiated Services (DiffServ) provides policy-based management

mechanisms used for prioritizing network resources to meet the

requirements of specific traffic types on a per-hop basis. Each packet is

classified upon entry into the network based on access lists, IP Precedence

or DSCP values, or VLAN lists. Using access lists allows you select traffic

based on Layer 2, Layer 3, or Layer 4 information contained in each

packet. Based on network policies, different kinds of traffic can be marked

for different kinds of forwarding.