KS8995MAL Micrel Inc, KS8995MAL Datasheet - Page 31

• Manufacturer Part Number: KS8995MAL
• Description: IC SWITCH 10/100 5PORT 128PQFP
• Manufacturer: Micrel Inc

Specifications of KS8995MAL

• Applications: *
• Mounting Type: Surface Mount
• Package / Case: 128-MQFP, 128-PQFP
• For Use With: 576-1017 - BOARD EVAL EXPERIMENT KS8995M
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

Port Mirroring Support
KS8995MA supports “port mirror” comprehensively as:
Multiple ports can be selected to be “rx sniffed” or “tx sniffed.” And any port can be selected to be the “sniffer port.” All these
per port features can be selected through Register 17.
VLAN Support
KS8995MA supports 16 active VLANs out of 4096 possible VLANs specified in IEEE 802.1q. KS8995MA provides a 16-entry
VLAN table, which converts VID (12 bits) to FID (4 bits) for address look-up. If a non-tagged or null-VID-tagged packet is
received, the ingress port VID is used for look-up. In the VLAN mode, the look-up process starts with VLAN table look-up to
determine whether the VID is valid. If the VID is not valid, the packet will be dropped and its address will not be learned. If the
VID is valid, FID is retrieved for further look-up. FID+DA is used to determine the destination port. FID+SA is used for learning
purposes.
May 2005
KS8995MA
Static MAC table
DA found in
1. “Receive Only” mirror on a port. All the packets received on the port will be mirrored on the sniffer port. For example,
2. “Transmit Only” mirror on a port. All the packets transmitted on the port will be mirrored on the sniffer port. For
3. “Receive and Transmit” mirror on two ports. All the packets received on port A AND transmitted on port B will be
port 1 is programmed to be “rx sniff,” and port 5 is programmed to be the “sniffer port.” A packet, received on port
1, is destined to port 4 after the internal look-up. The KS8995MA will forward the packet to both port 4 and port 5.
KS8995MA can optionally forward even “bad” received packets to port 5.
example, port 1 is programmed to be “tx sniff,” and port 5 is programmed to be the “sniffer port.” A packet, received
on any of the ports, is destined to port 1 after the internal look-up. The KS8995MA will forward the packet to both
ports 1 and 5.
mirrored on the sniffer port. To turn on the “AND” feature, set Register 5 bit 0 to 1. For example, port 1 is programmed
to be “rx sniff,” port 2 is programmed to be “transmit sniff,” and port 5 is programmed to be the “sniffer port.” A packet,
received on port 1, is destined to port 4 after the internal look-up. The KS8995MA will forward the packet to port 4
only, since it does not meet the “AND” condition. A packet, received on port 1, is destined to port 2 after the internal
look-up. The KS8995MA will forward the packet to both port 2 and port 5.
Yes
Yes
Yes
Yes
No
No
USE FID Flag?
Don’t care
Don’t care
0
1
1
1
Table 7. FID+DA Look-Up in the VLAN Mode
FID Match?
Don’t care
Don’t care
Don’t care
Yes
No
No
Dynamic MAC table
DA+FID found in
Don’t care
Don’t care
31
Yes
Yes
No
No
Action
Broadcast to the membership ports defined in the
VLAN table bit [20:16].
Send to the destination port defined in the
dynamic MAC table bit [54:52].
Send to the destination port(s) defined in the
static MAC table bit [52:48].
Broadcast to the membership ports defined in
the VLAN table bit [20:16].
Send to the destination port defined in the
dynamic MAC table bit [54:52].
Send to the destination port(s) defined in the
static MAC table bit [52:48].
M9999-051305
Micrel, Inc.