HP Virtual Connect: Common Myths, Misperceptions, and Objections, Second Edition
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Appendix B: Definitions 
Table 1. Definitions
Term  Definition 
ACL (VACL)  Access Control List or VLAN Access Control List: A set of rules 
that allows or disallows network traffic to 
flow between 
network devices 
BPDU  Bridge Protocol Data Unit: A spanning tree configuration frame 
exchanged between switches in the same spanning tree 
domain 
CX-4  An industry standard cabling specification used by VC for 
network connectivity using 10Gb Ethernet over copper. 
DAC  Direct Attached Cable: A copper cable with SFP+ transceivers 
directly attached. 
Downlink 
An internal port (enclosure midplane) on an Interconnect 
Module (blade switch or Virtual Connect) that directly connects 
to a server blade’s NIC port. 
External Network  The network and associated network devices external to the VC 
domain 
FlexNICs (Physical Functions)  One of four virtual NIC partitions available per Flex-10 Nic 
port. Each capable of being tuned from 100Mb to 10Gb
. 
Only supported with Virtual Connect Flex-10 I/O modules. 
Flex-10 NIC Port  A physical 10Gb port that is capable of being partitioned into 
4 Flex NICs. Only supported with Virtual Connect Flex-10 I/O 
modules. 
Hypervisor  A virtual machine hypervisor such as VMware ESX, Microsoft 
Hyper-V, Citrix XenServer, etc.  
Internal Cross-Connect  A non-visible port that interconnects two horizontally adjacent 
VC-Enet modules 
LACP  Link Aggregation Control Protocol (IEEE 802.3ad): A link 
aggregation configuration frame exchanged between two 
devices that form a logical port trunk/channel between them. 
LAG 
Link Aggregation Group: 802.3ad terminology for a port 
trunk/channel group. 
LLDP  Link Layer Discovery Protocol. An IEEE 802.1ab protocol that 
provides CDP-like functionality 
Logical Path  A single physical port or a single port channel. Both represent 
a single communication path.  
LOM  LAN on Motherboard. A NIC embedded on the system board 
of a server. 
NAT  Network Address Translation: A feature that allows a network 
device (such as a switch or router) to replace/rewrite 
addresses within a frame with a different address. 
NPIV  N-Port ID Virtualization: ANSI T11 feature for Fibre Channel 
that allows multiple WWNs to login to the fabric over a single 
N-Port.  
Port Trunk (Channel Group)  A group of two or more ports that operate as a single logical 
port and single logical path for the purposes of load 
balancing. 802.3ad and EtherChannel are both port trunking 
technologies . 
Quality of Service (QoS) 
A very broad term associated with network traffic 










