IBM xSeries 200, Hardware Maintenance Manual

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Cisco Fast EtherChannel (FEC) creates a team of two to four adapters to
increase transmission and reception throughput. FEC also includes the AFT
option. You can use FEC only with a switch that has FEC capability.
Teaming requires you to install at least one additional Ethernet adapter. For
additional information about the teaming modes, refer to the documentation that
comes with these additional adapters.
Priority Packet mode: Priority Packet is a traffic-prioritization utility that enables
you to set up filters to process high-priority traffic before normal traffic. You can
send information from critical nodes or applications with an indicated priority.
Because you set this priority at the host or entry point of the network, the network
devices can base forwarding decisions on priority information defined in the
packet.
Priority Packet information is available on the IBM Networking Web site at
http://www.ibm.com/networking/support.
Priority Packet prioritizes traffic based on priority filters. These are parameters you
assign to outgoing (transmit) packets. Using the Priority Filter Wizard, you can set
up predefined or custom priority filters based on a node medium access control
(MAC) address, Ethernet type, or by various properties of the protocol and
connector. Priority Packet provides two different methods for prioritizing traffic:
IEEE 802.1p tagging and High Priority Queue.
IEEE 802.1p is an IEEE standard for tagging, or adding additional bytes of
information to packets with different priority levels. Packets are tagged with 4
additional bytes, which increase the packet size and indicate a priority level. When
you send these packets out on the network, the higher priority packets are
transferred first. Priority packet tagging (also known as Traffic Class Expediting)
enables the adapter to work with other elements of the network (such as switches
and routers) to deliver priority packets first. You can assign specific priority levels
from 0 (low) to 7 (high).
You can assign values to packets based on their priority when you use the IEEE
802.1p standard for packet tagging. This method requires a network infrastructure
that supports packet tagging. The routing devices receiving and transferring these
packets on your network must support 802.1p for tagging to be effective.
After you set up the priority filter in Priority Packet, you must start IBMSet and
select 802.1p/802.1Q Tagging on the Advanced tab.
Note: IEEE 802.1p tagging increases the size of the packets it tags. Some hubs and
switches will not recognize the larger packets and will drop them. Check
your hub or switch documentation to see if they support 802.1p. (You can
configure the switch to strip the tags from the packets and send it on to the
next destination as normal traffic.) If these devices do not support 802.1p, or
if you are not sure, use high priority queue (HPQ) to prioritize network
traffic.
The requirements for effectively using IEEE 802.1p tagging are:
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The other devices receiving and routing 802.1p tagged packets must support
802.1p.
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The adapters on these devices must support 802.1p. The Ethernet controller in
your xSeries 200 and all IBM 10/100 Ethernet Security Adapters support 802.1p.
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xSeries 200 Type 8479 and xSeries 200VL Type 8481: Hardware Maintenance Manual