ZyXEL Communications GS-4024 User Manual page 33

GS-4024 User's Guide
VLAN Stacking
Use VLAN stacking to add an outer VLAN tag to the inner IEEE 802.1Q tagged frames that
enter the network. By tagging the tagged frames ("double-tagged" frames), the service
provider can manage up to 4,094 VLAN groups with each group containing up to 4,094
customer VLANs. This allows a service provider to provide different service, based on
specific VLANs, for many different customers.
Differentiated Services (DiffServ)
With DiffServ, the switch marks packets so that they receive specific per-hop treatment at
DiffServ-compliant network devices along the route based on the application types and traffic
flow.
Classifier and Policy
You can create a policy to define actions to be performed on a traffic flow grouped by a
classifier according to specific criteria such as the IP address, port number or protocol type,
etc..
Queuing
Queuing is used to help solve performance degradation when there is network congestion.
Two scheduling services are supported: Strict Priority Queuing (SPQ) and Weighted Round
Robin (WRR). This allows the switch to maintain separate queues for packets from each
individual source or flow and prevent a source from monopolizing the bandwidth.
Port Mirroring
Port mirroring allows you to copy traffic going from one or all ports to another or all ports in
order that you can examine the traffic from the mirror port (the port you copy the traffic to)
without interference.
Static Route
Static routes tell the switch how to forward IP traffic when you configure the TCP/IP
parameters manually.
IGMP
IGMP (Internet Group Multicast Protocol) is a session-layer protocol used to establish
membership in a multicast group - it is not used to carry user data.
IGMP Snooping
The switch supports IGMP snooping enabling group multicast traffic to be only forwarded to
ports that are members of that group; thus allowing you to significantly reduce multicast
traffic passing through your switch.
32 Chapter 1 Getting to Know Your Switch