LevelOne GEL-5261, Руководство пользователя

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Chapter 1
| Introduction
Description of Software Features
◆ 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 protocol VLANs to restrict traffic to specified interfaces based on protocol
type.
IEEE 802.1Q Tunneling
(QinQ)
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.
Traffic Prioritization
This switch prioritizes each packet based on the required level of service, using
eight priority queues with strict priority, Weighted Round Robin (WRR) scheduling,
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, or IP Precedence. 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.
Quality of Service
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.
Ethernet Ring
Protection Switching
ERPS can be used to increase the availability and robustness of Ethernet rings, such
as those used in Metropolitan Area Networks (MAN). ERPS provides Layer 2 loop
avoidance and fast reconvergence in Layer 2 ring topologies, supporting up to 255
nodes in the ring structure. It can also function with IEEE 802.1ag to support link
monitoring when non-participating devices exist within the Ethernet ring.