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v Cisco Fast EtherChannel (FEC) creates a team of two to four adapters to
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 you can
use 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 that is 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 that
you assign to outgoing (transmit) packets. Using the Priority Filter Wizard, you can
set up predefined or custom priority filters based on a node (MAC) address,
Ethernet type, or by various properties of the protocol and port. Priority Packet
provides two different methods for prioritizing traffic: IEEE 802.1p tagging and
High Priority Queue.
IEEE 802.1p is a new 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 that receive and transfer 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 that it tags. Some hubs
The requirements for effectively using IEEE 802.1p tagging are:
v The other devices receiving and routing 802.1p tagged packets must support
v The adapters on these devices must support 802.1p. The Ethernet controller in
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Hardware Maintenance Manual: xSeries 220 Type 8645
increase transmission and reception thoughput. FEC also includes the AFT
option. You can use FEC only with a switch that has FEC capability.
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.
802.1p.
the xSeries 220 and all IBM 10/100 Ethernet Security Adapters support 802.1p.
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