Mitel MiVOICE BUSINESS, Engineering Manualline

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Engineering Guidelines
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COS – Class of Service. This refers to the priority value in the Layer 2 part of an IP packet
when IEEE 802.1p is used.
CPH – Calls Per Hour. For example, 6 CPH means 6 calls per hour.
CSM – Customer Service Manager. Former name for MiContact Center Office, an entry level
contact center solution hosted on MiCollab for basic contact centers or workgroups with up to
100 agents.
CSMA/CD – Carrier Sense Multiple Access Collision Detect. The mechanism used on
shared Ethernet connections to ensure that devices are not sending at the same time, and if
they are, to initiate a back-off and retry algorithm.
CTI – Computer Telephony Integration. Means of combining computer functions to control
operation of telephony equipment.
Datagram – A logical grouping of information sent as a network layer unit over a transmission
medium without prior establishment of a virtual circuit. IP datagrams are the primary information
units in the Internet. The terms “frame”, “message” and “packet” are also used to describe a
datagram.
DECT – Digital Enhanced Cordless Telephony. Originally this was a European standard for
digital cordless phones. This is now a worldwide standard, hence, the name change to
Enhanced. Standard DECT phones are not available in North America.
DHCP – Dynamic Host Configuration Protocol. A means of passing out IP addresses in a
controlled manner from a central point/server.
DiffServ – Differentiated Services. DiffServ is a protocol for specifying and controlling network
traffic by class so that certain types of traffic get precedence. For example, voice traffic, which
requires a relatively uninterrupted flow of data, might get precedence over other kinds of traffic.
Differentiated Services is the most advanced method for managing traffic in WAN connections.
This uses the Type of Service field at Layer 3 in an IP packet. See also DSCP.
DN – Directory Number. A telephone or extension number.
DNIC – Digital Network Interface Circuit. A chip used as the basis for several sets which
handle both voice and data.
DNS – Domain Name Server. A means of translating between typed names and actual IP
addresses, e.g. microsoft.com = 207.46.134.222
DPNSS – Digital Private Network Signalling System. A British common channel signalling
protocol for requesting or providing services from/to another PBX.
DSCP – Differentiated Services Code Point. This is a value that is assigned to the Type of
Service byte in each outgoing packet. The value can be in the range of 0 to 63 and allows
routers at Layer 3 to direct the data to an appropriate queue. Value 46 is recommended for
voice and will use the Expedited Forwarding queue or Class of Service.
DSP – Digital Signal Processor. This is a programmable device that can manipulate signals,
such as audio, to generate and detect a range of signals, e.g. DTMF signalling.