Edge-Core ECS4510-12PD Web Management Manual page 36

Chapter 1
| Introduction
Description of Software Features
T P
RAFFIC RIORITIZATION
Q S
UALITY OF ERVICE
M F
ULTICAST ILTERING
L L D
INK AYER ISCOVERY
P
ROTOCOL
internal VLAN IDs. This is accomplished by inserting Service Provider VLAN
(SPVLAN) tags into the customer's frames when they enter the service provider's
network, and then stripping the tags when the frames leave the network.
This switch prioritizes each packet based on the required level of service, using four
priority queues with strict priority, Weighted Round Robin (WRR), or a combination
of strict and weighted 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 using DSCP, or IP Precedence. 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.
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.
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, to be transmitted across a single network-wide multicast VLAN shared by
hosts residing in other standard or private VLAN groups, while preserving security
and data isolation for normal traffic.
LLDP is used to discover basic information about neighboring devices within the
local broadcast domain. LLDP is a Layer 2 protocol that advertises information
about the sending device and collects information gathered from neighboring
network nodes it discovers.
Advertised information is represented in Type Length Value (TLV) format according
to the IEEE 802.1ab standard, and can include details such as device identification,
capabilities and configuration settings. Media Endpoint Discovery (LLDP-MED) is an
extension of LLDP intended for managing endpoint devices such as Voice over IP
phones and network switches. The LLDP-MED TLVs advertise information such as
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