Lucent Technologies P550 - Manual (Page 34)

Cajun P550 Switch Overview
1-14 Cajun P550/P220 Switch Operation Guide
Buffer and Queue Management
Adding gigabit speeds to existing networks means that there can be a huge disparity
between link speeds. For example, anything more than a 1% load on a gigabit link could
easily overwhelm a 10 Mb/s Ethernet link.
Without queue and buffer management, gigabit links might only move congestion in a
network, rather than relieving it. The switch employs the following buffer and queue
management techniques:
❒ Configurable active backpressure:
• Half-duplex ports use active backpressure to jam input ports when their frame
buffers are full.
• Full-duplex links use IEEE 802.3z pause control frames to pause traffic when
buffers are full.
❒ Packed frame buffers for optimal memory utilization. The memory management
allows virtually 100% utilization of buffer memory.
❒ Two Class of Service priority queues that provide flexible queue management
algorithms to meet application requirements.
❒ Large buffer space:
• 512 KB per gigabit port.
• 128 KB additional for outbound 10/100 ports.
❒ Configurable queue depth for each of two prioritized packet queues.
❒ Configurable priority threshold.
Web-Based Management
Web-based management allows you to manage switches from any station connected to
your network.
The switch offers a command line interface and a rich set of web-based management
features:
❒ Reduced Instruction Set Computing- based (RISC) Supervisor provides high-speed
VLAN, RMON, and network management support.
❒ Web Agent: Built-in SNMP and HTML-based agent, compatible with popular Web
browsers, provides top-to-bottom switch management.