HP StorageWorks Fabric OS 5.X Master Glossary (AA-RW7NA-TE, September 2005)

datagram A Class 3 Fibre Channel service that allows data to be sent quickly to devices
attached to the fabric, without receipt confirmation.
data word A type of transmission word that occurs within frames. The frame header, data
field, and CRC all consist of data words.
See also frame, ordered set,andtransmission word.
DCC Direct cable connection. A t ype of connection that does not require network
interface cards (NICs), m aking it relatively inexpensive and simple; however, it
provides a limited connection between two PCs, and the data transfer rate is
slower than wi th a true LAN.
DCE Data Communications Equipment. Usually refers to a modem.
dedicated simplex A connection method that permits a single N_Port to simultaneously initiate a
session with one N_Por t as a n initiator and have a separate Class 1 connection
to another N _Port as a recipient.
defined zone con-
figuration
The complete set of all zone objects defined in the fabric. Can include multiple
zone configu rations.
See also effective zone configuration, enabled zone configuration,andzone
configuration.
deskew Related to the HP Trunking feature. The time difference between traffictraveling
over each ISL other than the shortest ISL in the group and traffictravelingover
that shortest ISL. The deskew number corresponds to nanoseconds divided by
10. The firmware automatically sets the minimum deskew value of the shortest
ISL to 15.
DH-CHAP Diffie-Hellman Challenge-Handshake Authentic ation Protocol. An
implementation of CHAP using Diffie-Hellman encryption.
See also CHAP.
DHCP Dynamic Host Configuration Protocol. Provides a way to automate and m a nag e
the net work configuration of desktop computers and other network devices
that use the TCP/I P protocol.
DHCPD Dynamic Host Configuration Protocol daemon.
D_ID Destination identifier. A 3-byte field in the fram e header, used to indicate the
address identifier of the N_Port to which the frame is headed.
digital certificate An electronic document issued by a CA (certificate authority) to an entity,
containing the public key and identity of the entit y. Entities i n a secure fabric
are authenticated based on these cer tifi cates.
See also authentication, CA ,andpublic key.
director The HP StorageWorks Core Switch 2/64, SAN D irector 2 /128, or 4/256
SAN Director.
disparity The proportion of ones and zeroes in an encoded character. Neutral disparity
means an equal number of each, Positive disparity means a majority of ones,
and Negative disparity means a majorit y of zeroes.
DLS Dynamic load-sharing. Dynamic distribution of traffic over available paths.
Allows for recomputing of routes when an Fx_Port or E_Port changes status.
DMTF Distributed Management Task Force. An organization that promotes the
development of management standards for enterprise and Internet environments.
Its purpose is to allows the exchange of management information in order to
develop multi-vendor interoperability.
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Glossary