General Description
The RTL8309N is an 8-port Fast Ethernet switch controller that integrates eight MACs, and eight physical layer transceivers for 10Base-T and 100Base-TX operation into a single chip.
The RTL8309N contains a 2K-entry address lookup table. Two 4-way associative hash algorithms avoid hash collisions and maintain forwarding performance.
Maximum packet length can be 2K bytes. Three types of independent storm filters are provided to filter packet storms, and an intelligent switch engine prevents Head-of-Line blocking problems.
The RTL8309N supports 16 VLAN groups. These can be configured as port-based VLANs and/or 802.1Q tag-based VLANs. The RTL8309N also supports four Independent VLAN Learnings (IVLs).

FEATUREs
Basic Switching Functions
■ 8-port switch controller with transceiver for
   10Base-T and 100Base-TX with:
   ◆ 8-port 10/100M UTP
■ Non-blocking wire-speed reception and
   transmission and non-head-of-line-blocking
   forwarding
■ Complies with IEEE 802.3/802.3u
   auto-negotiation
■ Built-in high efficiency SRAM for packet
   buffer, with 2K-entry lookup table and two
   4-way associative hash algorithms
■ 2K byte maximum packet length
■ Flow control fully supported:
   ◆ Half duplex: Back pressure flow control
   ◆ Full duplex: IEEE 802.3x flow control

Service Quality
■ Supports high performance QoS function on
   each port:
   ◆ Supports 4-level priority queues
   ◆ Weighted round robin service
   ◆ Supports strict priority
   ◆ Input/Output port bandwidth control
   ◆ Queue based bandwidth control
   ◆ 1Q-based, Port-based, DSCP-based, IP
      address-based, and other types of priority
      assignments
■ Supports IEEE 802.1p Traffic Re-marking

Security and Management
■ Supports reserved control frame filtering
■ Supports advanced storm filtering
■ Optional EEPROM interface for
   configuration
     
VLAN Functions
■ Supports up to 16 VLAN groups
■ Flexible 802.1Q port/tag-based VLAN
■ Supports four IVLs
■ Leaky VLAN for
   unicast/multicast/broadcast/ARP packets
   Power Saving Functions
■ Supports Energy-Efficient Ethernet (EEE)
   function (IEEE 802.3az)
■ Link down Power Saving Mode

Diagnostic Functions
■ Supports hardware loop detection function,
   with LEDs to indicate the existence of a
   loop
■ Supports cable diagnosis (RTCT function)
■ LED indicators:
   ◆ Loop status indication
   ◆ RTCT status indication
   ◆ LEDs blink upon reset for LED
      diagnostics
     
Other Features
■ Optional MDI/MDIX auto crossover for
   plug-and-play
■ Physical layer port Polarity Detection and
   Correction function
■ Robust baseline wander correction for
   improved 100Base-TX performance
■ 25MHz crystal
■ Integrated LDO regulator to generate 1.0V
   from 3.3V via one external Diode
■ Low power, 1.0/3.3V, 55nm CMOS
   technology
■ 64-pin QFN package