Ericsson ECN330, Руководство пользователя

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Management Features Overview
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1553-KDU 137 365 Uen D 2006-06-16
Traffic Prioritization – The ECN330-switch prioritizes each packet based on
the required level of service, using eight priority queues with strict priority,
Weighted Round Robin (WRR) or Weighted Fair Queueing (WFQ) scheduling.
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.
The ECN330-switch also supports several common methods of prioritizing
Layer 3 and 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 or the
number of the TCP or UDP port. When these services are enabled, the priorities
are mapped to a Class of Service value by the ECN330-switch, and the traffic
then sent to the corresponding output queue.
IP Routing – The ECN330-switch provides Layer 3 IP routing. To maintain a
high rate of throughput, the ECN330-switch forwards all traffic passing within the
same segment, and routes only traffic that passes between different
subnetworks. The wire-speed routing provided by the ECN330-switch lets
network segments or VLANs be easily linked together without having to deal
with the bottlenecks or configuration hassles normally associated with
conventional routers.
Routing for unicast traffic is supported with the Routing Information Protocol
(RIP) and the Open Shortest Path First (OSPF) protocol.
• RIP – This protocol uses a distance-vector approach to routing. Routes
are determined on the basis of minimizing the distance vector, or hop
count, which serves as a rough estimate of transmission cost.
• OSPF – This approach uses a link state routing protocol to generate a
shortest-path tree, then builds up its routing table based on this tree.
OSPF produces a more stable network because the participating
routers act on network changes predictably and simultaneously,
converging on the best route more quickly than RIP.
Router Redundancy – Virtual Router Redundancy Protocol (VRRP) uses a
virtual IP address to support a primary router and multiple backup routers. The
backups can be configured to take over the workload if the master fails or to load
share the traffic. The primary goal of this protocol is to allow a host device which
has been configured with a fixed gateway to maintain network connectivity in
case the primary gateway goes down.