Management Features Overview
28 1553-KDU 137 365 Uen D 2006-06-16
Address Resolution Protocol – The ECN330-switch uses ARP and Proxy
ARP to convert between IP addresses and MAC (hardware) addresses. The
ECN330-switch supports conventional ARP, which locates the MAC address
corresponding to a given IP address. This allows the ECN330-switch to use IP
addresses for routing decisions and the corresponding MAC addresses to
forward packets from one hop to the next. Either static or dynamic entries can
be configured in the ARP cache.
Proxy ARP allows hosts that do not support routing to determine the MAC
address of a device on another network or subnet. When a host sends an ARP
request for a remote network, the ECN330-switch checks to see if it has the best
route. If it does, it sends its own MAC address to the host. The host then sends
traffic for the remote destination through the ECN330-switch, which uses its own
routing table to reach the destination on the other network.
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 traffic to be selected
based on the 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 ECN330-switch uses IGMP Snooping and Query at Layer 2 and IGMP at
Layer 3 to manage multicast group registration.
Multicast Routing – Routing for multicast packets is supported by the Distance
Vector Multicast Routing Protocol (DVMRP) and Protocol-Independent
Multicasting - Dense Mode and Sparse Mode (PIM-DM, PIM-SM). These
protocols work in conjunction with IGMP to filter and route multicast traffic.
DVMRP is a comprehensive Multicast Router method that maintains its own
routing table, but is gradually being replacing by most network managers with
PIM, Dense Mode and Sparse Mode. PIM is a very simple protocol that uses the
routing table of the unicast routing protocol enabled on an interface. Dense
Mode is designed for areas where the probability of multicast clients is relatively
high, and the overhead of frequent flooding is justified. While Sparse mode is
designed for network areas, such as the Wide Area Network, where the
probability of multicast clients is low.
To Next Page
Loading...
