SMC Networks 7824M/FSW - annexe 1, Management Manual

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I
NTRODUCTION
1-7
• 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.
Traffic Prioritization – This switch prioritizes each packet based on the
required level of service, using eight priority queues with strict or Weighted
Round Robin 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 or the
number of the TCP/UDP port. 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.
Multicast Filtering – Specific multicast traffic can be assigned to its own
VLAN to ensure that it does not interfere with normal network traffic and
to guarantee real-time delivery by setting the required priority level for the
designated VLAN. The switch uses IGMP Snooping and Query to manage
multicast group registration. It also supports Multicast VLAN Registration
(MVR) which allows common multicast traffic, such as television channels,