ZyXEL Communications VES-1616F-44, User Manual

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VES-1616F/1624F-44 User’s Guide
30 Chapter 1 Getting to Know Your Switch
DHCP
DHCP (Dynamic Host Configuration Protocol RFC 2131 and RFC 2132) allows individual
computers to obtain TCP/IP configuration at start-up from a server. You can configure the
switch as a DHCP server or disable it. When configured as a server, the switch provides the
TCP/IP configuration for the clients. If you disable the DHCP service, you must have another
DHCP server on your LAN, or else the computer must be manually configured.
VLAN
A VLAN (Virtual Local Area Network) allows a physical network to be partitioned into
multiple logical networks. Devices on a logical network belong to one group. A device can
belong to more than one group. With VLAN, a device cannot directly talk to or hear from
devices that are not in the same group(s); the traffic must first go through a router.
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.
Multicast VLAN Registration (MVR)
MVR is designed for applications (such as Media-on-Demand (MoD)) using multicast traffic
across an Ethernet ring-based service provider network. MVR allows one single multicast
VLAN can be shared among different subscriber VLANs on the network. This improves
bandwidth utilization with reduced multicast traffic in the subscriber VLANs and easy
multicast group management.
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 Fair
Scheduling (WFS). This allows the switch to maintain separate queues for packets from each
individual source or flow and prevent a source from monopolizing the bandwidth.