IBM xSeries 330 - Manual (Page 77)

Chapter 5. Installing options 69
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:
• The other devices receiving and routing 802.1p tagged packets must support
802.1p.
• The adapters on these devices must support 802.1p. The Ethernet controller in all
IBM Netfinity 10/100 Ethernet Security Adapters and IBM 10/100 Ethernet
Server Adapters support 802.1p.
• The adapter cannot be assigned to an adapter team.
• If you are setting up VLANs and packet tagging on the same adapter,
802.1p/802.1Q Tagging must be enabled on the IBMSet Advanced tab.
If your network infrastructure devices do not support IEEE 802.1p or you are not sure,
you can still define filters and send packets as high priority. While High Priority
Queue (HPQ) does not provide the precise priority levels of 802.1p tagging, it does
assign traffic as either high or low priority and sends high priority packets first.
Therefore, if there are multiple applications on a system sending packets, the packets
from the application with a filter are sent out first. HPQ does not change network
routing, nor does it add any information to the packets.
To assign HPQ, you can specify it using Priority Packet when you create or assign a
filter.
To effectively use HPQ tagging, the adapter cannot be assigned to an adapter team.
Virtual LAN Mode: A virtual LAN (VLAN) is a logical grouping of network devices
put together as a LAN, regardless of their physical grouping or collision domains.
Using VLANs increases network performance and improves network security.
VLANs offer you the ability to group users and devices together into logical
workgroups. This can simplify network administration when connecting clients to
servers that are geographically dispersed across the building, campus, or enterprise
network.
Normally, VLANs are configured at the switch and any computer can be a member of
one VLAN per installed network adapter. Your Ethernet controller supersedes this by
communicating directly with the switch, allowing multiple VLANs on a single
network adapter (up to 64 VLANs).
To set up VLAN membership, your Ethernet controller must be attached to a switch
that has VLAN capability. You also need to use Windows NT 4.0 or later, or Novell
NetWare 4.1x or later.
Notes:
1. Windows NT versions prior to 4.0 do not support VLANs.
2. VLANs require NT 4.0 with Service Pack 3.0 and the NDIS driver hotfix from
Microsoft.
3. In Windows NT, VLANs cannot be implemented on controllers that have been
configured for teaming options. NetWare can support teaming options and
VLANs on the same adapters.
To join a VLAN from Windows NT 4.0: