Security Solutions

PFC Priority flow control. An extension of the 802.3x mechanism and defined in IEEE 802.1Qbb to

define a lossless Ethernet connection. The PAUSE frame contains an 8–bit bit mask of the 802.1p

priorities (specifying which traffic classes should be paused) and a timer for each priority specifying

how long the traffic in that priority class should be paused. The per-priority PAUSE mechanism

allows the storage array to tell the switch that it should stop sending just the FCoE traffic (assuming

FCoE traffic is marked with priority value=3).

QoS Quality of service. A traffic management feature.

QSFP+ Quad Small form-factor pluggable, plus transceiver. A hot-pluggable, high-density transceiver

which provides four channels of traffic in each direction (Tx and Rx). QSFP+ supports up to 16

Gb/s per channel for applications such as 40G Ethernet and InfiniBand 4xQDR. Both multimode

and single mode versions of the QSFP+ module are available, as well as QSFP-based active

optical cables.

SFP+ Small form-factor pluggable, plus transceiver. A compact, hot-pluggable transceiver which provides

one channel of traffic in each direction (Tx and Rx). SFP+ supports up to 16 Gb/s per channel

for applications such as 10G Ethernet, 16/8/4 G FC and is used for both telecom and datacom

applications.

soft zone A fabric name service that allows each device to query the addresses of all other devices. Soft

zoning restricts only the fabric name service to show only an allowed subset of devices. Therefore,

when a server looks at the content of the fabric, it will only see the devices it is allowed to see.

However, any server can still attempt to contact any device on the network by address. Soft

zoning is similar to the computing concept of security through obscurity.

ToR Top of Rack. A design that contains servers connected to one or two converged network switches

installed inside the rack. The term top of rack has been coined for this design. However, the

actual physical location of the switch does not necessarily need to be at the top of the rack. Other

switch locations could be bottom of the rack or middle of rack, however, top of the rack is most

common due to easier accessibility and cleaner cable management. This design may also

sometimes be referred to as In-Rack. The key characteristic and appeal of the Top of Rack design

is that all copper cabling for servers stays within the rack as relatively short patch cables from

the server to the rack switch. The switch links from the rack to the data center network using fiber

running directly from the rack to a common aggregation area connecting to redundant Distribution

or Aggregation high density modular converged switches.

vE_Port Virtual Extension port. FCoE switch ports that provide direct switch-to-switch connections within

the fabric.

vF_Port Virtual Fabric Port. FCoE switch ports that attach to vN_Ports or vNP ports. The data forwarding

component of an FC entity that emulates an F_Port and is dynamically instantiated on successful

completion of an FLOGI Exchange. The term virtual indicates the use of a non Fibre Channel link

connecting a VF_Port with a VN_Port.

VFC Virtual Fibre Channel. An interface that must be enabled and mapped to and FCoE VSAN, which

has an associated VLAN. Each physical switch port that will carry FCoE traffic must have a

corresponding VFC interface.

VLAN Virtual LAN (ID). A group of end stations with a common set of requirements, independent of

physical location. VLANs have the same attributes as a physical LAN but allow you to group end

stations even if they are not located physically on the same LAN segment. VLANs are usually

associated with IP subnetworks. For example, all the end stations in a particular IP subnet belong

46 Glossary