Datasheet

Alcatel-Lucent Page 66
OmniSwitch 9000
physical long-frame-size of the egress port as the MTU. When the ASIC attempts to forward a packet,
it tests the size of the packet against the physical long-frame-size of the egress port, if the packet is too
large, it forwards the packet to the CPU for fragmentation (or ICMP processing in the case of a packet
with Do not Fragment set).
• 10/100 ports are set with a long-frame-size of 1553 bytes.
• GigE/10GigE ports are set with a long-frame-size of 9216 bytes (jumbo frames). 4.1.7
Packets larger than the long-frame-size are dropped at ingress. The above (& default) values are the
maximum configurable values.
Packets that are forwarded from a 10/100 to a 10/100 port cannot ever be reported as too big via ICMP
because anything larger than 1553 would not be accepted.
The same holds true for packets forwarded between two GigE/10GigE ports and from a 10/100 port to
a GigE/10GigE.
Layer-2 Ethernet Frame Size:
Untagged: 1,518 Bytes without IEEE 802.1Q tags
Tagged: 1,522 Bytes with IEEE 802.1Q tags
Long Frame Size (enabled by default): 1553 Bytes (IEEE 8021.Q tagged or untagged)
Frame Type: Type2, LLC, SNAP, RAW 802.3
The maximum frame size on the Gigabit Ethernet interfaces range from 1,518 to 9,216 Bytes
Jumbo frames up to 9K Bytes (9,216 Bytes) are supported on ALL Module types including the
OS9-XNI-U2 & OS9-XNI-U6 (10-Gigabit Ethernet Modules).
Untagged (without IEEE 802.1Q tags) Ethernet Packets: 1,518 Bytes
Tagged (with IEEE 802.1Q tags) Ethernet Packets: 1,522 Bytes
Inter-Frame Gap 12 Bytes (by default)
Inter-frame gap is a measure of the minimum idle time between the end of one frame transmission and
the beginning of another. By default, the inter-frame gap is 12 bytes.
Through the use of “interfaces ifg” Command, the inter-frame gap value (in bytes) on a specific port, a
range of ports, or all ports on a switch (slot) can be configured. Values for this command range from 9
to 12 bytes. Note. This command is only valid on Gigabit ports.
Interface Alias (Port Alias) Supported (none configured by default): Through the use of this feature an alias (i.e., description) for a
single port can be configured. (You cannot configure an entire switch or a range of ports.) The text
description can be up to 40 characters long.
Peak Flood Rate Configuration By default:
4 Mbps (10 Ethernet)
49 Mbps (100 Fast Ethernet)
496 Mbps (1 Gigabit Ethernet)
997 Mbps (10 Gigabit Ethernet)
Through the use of this feature, the peak ingress flood rate value on a specific port, a range of ports, or
all ports on a switch (slot) in megabits per second can be configured.
Note. The user can configure a flood rate equal to the line rate, but it is not recommended.
Alcatel.Lucent recommends that you always configure the flood rate to be less than the line speed.
Flow Control The flow command can be used to enable (the default) or disable flow control on a specific port, a
range of ports, or all ports on an entire switch (slot). When the buffers on a receiving device are full,
flow control transmits pause frames to the remote link partner to delay transmission. The local port can
delay transmission of data if the remote link partner transmits a pause frame. By default, the flow
control wait time is 0 microseconds.
IEEE 802.3x (programmable threshold) flow control. – Enabled by default
(Note: the switch supports and honors the incoming IEEE 802.3x pause frames, but it does not
generate outgoing IEEE 802.3x pause frames)
Trap Port Link Messages Supported (disabled by default)
This feature can be enabled or disabled (the default) on a specific port, a range of ports, or all ports on
a switch (slot). When enabled, a trap message will be displayed on a Network Management Station
(NMS) whenever the port state has changed.
Per port rate limiting
Per-port L2/L3 multicast & broadcast flood limit is
supported.
Per-port multicast / broadcast / flood limit is supported. The ASIC provides a per port configuration on
the incoming and/or outgoing port basis that allows broadcast and/or multicast storm control. The CPU
can program a threshold value per port that indicates the number of broadcast and/or multicast
packets/bytes that are allowed in a given time interval.
Re-settable Statistics Counters Supported
Duplex Mode support The duplex mode feature is supported on a specific port, a range of ports, or all ports on a switch (slot).
It can be set to full (full duplex mode, which is the default on fiber ports), half (half duplex mode), and
auto (auto-negotiation, which is the default on copper ports). The Auto option causes the switch to
advertise all available duplex modes (half/full/both) for the port during auto-negotiation. In full duplex
mode, the interface transmits and receives data simultaneously. In half duplex mode, the interface can
only transmit or receive data at a given time.
Auto-negotiation Auto-negotiation is supported (enabled by default). It can be enabled or disabled on a single port, a
range of ports, or an entire slot.
Crossover Crossover can be configured on a single port, a range of ports, or an entire slot. If auto negotiation is
disabled, auto MDIX, flow control, auto speed, and auto duplex are not accepted.