VIA Atlantic VT6528 Ethernet Switch Controller

VT6528 supports all today's most popular Layer 2 standards, including 802.1D self-learning bridge, Spanning Tree Protocol and Rapid Spanning Tree Protocol, 802.1Q VLAN, GVRP, 802.1p traffic priority, and 802.3ad Aggregation of Multiple Link Segments. In addition, to alleviate users' ever-growing network size and security concerns, VT6528 also supports 802.1s Multiple Spanning Trees and 802.1X Port-based Network Access Control.

Besides Layer 2 features, VT6528 provides Layer 3 assist features, including IGMP trapping and multicast routing protocol PDU snooping, IP multicasting, and IPv4 TOS/DiffServ based packet prioritization. Management features such as SNMP, MIB counters, and port mirroring are also supported to facilitate networks management and diagnostics.

Having the special requirements for today's broadband access switch in mind, VT6528 supports 512K Bytes packet buffer which greatly improves its ability to handle temporary network congestion caused by low user download speed and high uplink port speed, thus reducing chances of packet drop. Four egress queues, prioritized ingress rate policing and egress rate pacing further reduce chances of dropping high priority packets, resulting a more reliable network for real-time multimedia applications. Moreover, VT6528 features both tag exchange and double tagging to support traffic aggregation in provider networks.

Besides basic port-based network access control, VT6528 allows network administrators control over not only who can access the network, but also what a user can do with the access privilege. With VT6528's 256-entry deep access control list (ACL), IPv4 addresses and TCP/UDP port numbers of packets can be checked at wire speed. When illegal access is identified, the corresponding packets can be discarded immediately. To watch for DOS type of attack, a pair of private MIB counters is linked to each entry of ACL. These counters are incremented for each hit on the corresponding ACL entry, thus providing necessary statistics for identifying potential attacks.

Integrating IPv6 into existing network infrastructure is a challenging task. With VT6528, IPv6 traffic can be either forwarded to CPU port for processing, or redirected to other network devices through a dedicated port.

Key Features

» Ethernet switch controller - 24 10/100BaseX Ethernet ports and 2 10/100/1000BaseX Ethernet ports
» Supports SMII or SS-SMII for 10/100BaseX ports, Supports GMII/MII/TBI for 10/100/1000BaseX ports
» Supports 802.1D bridge self-learning, storing up to 8K+ 256 unicast or multicast addresses
» Broadcast storm filtering based on ingress port bandwidth
» HOL blocking prevention
» Deadlock relief
» Auto-polling via MDC/MDIO management interface for auto-configuration of speed, duplex mode, and flow control capability of all Ethernet ports
» Jumbo packets supported on per port and per VLAN basis
» Supports port tunneling / mirroring
» Supports 802.1D Spanning Tree Algorithm and Protocol, and 802.1w Rapid Reconfiguration
» Flexible per-port VLAN classification option supports co-existing of port-based VLAN domain and 802.1Q VLAN domain
» Supports Independent VLAN Learning (IVL) , Shared VLAN Learning (SVL), and 64 VLAN-dependent Spanning Trees
» Supports 802.1X Port-based Network Access Control, and 802.3ad Aggregation of Multiple Link Segments
» Supports 802.1p Traffic Priority
» Four priority egress queues per port
» Four RMON groups (1,2,3,9)
» Programmable LED output provides
» MAC address table synchronization assistance
» Asymmetric VLAN membership for better network security
» Port-based ingress rate policing and egress rate pacing
» Supports Layer 2/3/4 (Layer 2+) classification
» SMAC/SIP bindings for IPv4 packets can be implemented
» Four 4K VID spaces can be emulated on one switch
» 8/16-bit PIO interface, supported with LQFP package (VT6528)
» 32-bit PCI 2.2 compliant bus interface, selectable only with BGA package (VT6529)