Mitel MiVOICE BUSINESS, Engineering Manualline

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Engineering Guidelines
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OSPF – Open Shortest Path First. A link-state routing protocol used for routing IP traffic over
the most cost-efficient route.
PC – Personal Computer.
PCM – Pulse Code Modulation. The digital representation of analog signals.
PDA – Personal Digital Assistant. A handheld personal organizer that can interface to a PC
or a Mitel PDA Phone.
Permanent IP – An IP address that has been leased (from DHCP) on a permanent basis.
PI – Performance Index. A calculation of the performance limits of a system. Different weighting
values are assigned to various types of calls. Based on the expected calls per hour (CPH) of
all of the user ports on the system, a system performance index (PI) can be calculated. The
system PI is used as an indication of how much traffic the 3300 ICP can handle at any one time.
Ping – This is a means of sending a test message and waiting for a reply to determine if a
network device is reachable. On a PC, this is invoked with the command ping .
PPM – Parts Per Million. This is a measurement of accuracy, or the expected error in one
million events. Therefore 1 ppm means that 999,999 to 1,000,0001 events occurred when
1,000,000 were expected. This is 0.0001% error. For example, a household clock that is 1
second accurate per day is 11.5 ppm, or would need to be 0.086 seconds incorrect per day to
be 1 ppm.
PRI – Primary Rate Interface. This is a connection to the PSTN where a number of trunk
channels are multiplexed onto a common connection. Both T1 and E1 variants are available.
PSTN – Public Switched Telephone Network. The telephone network that provides local and
long distance connections, e.g. Bell, AT&T, BT.
PTT – Poste, Telefonie, Telegrafie. PSTN services. Often countries combine postal services
and telephony under a common service provider, e.g. the government.
RAD – Recorded Announcement Device.
RAID – Redundant Array of Independent Disks. Array of hard drives on which the information
is duplicated. A controller manages the disks, switching automatically from the primary to the
secondary in the event of the failure of the primary hard drive.
RDN – Remote Directory Number. The Remote DN Table is used to identify alternate ICPs
to check for availability of devices, and to determine if a device is located on the Primary or
Secondary ICP.
RFC – Request For Comments. A document that is created, maintained and distributed by
the Internet Engineering Task Force. An RFC is the vehicle that is used to discuss and evolve
a networking related protocol. RFCs usually get approved and issued as standards.
RFP – Radio Fixed Parts. The Radio Fixed Parts (RFPs) connect to the 3300 ICP through the
LAN. The wireless phones communicate with the RFPs using standard Digital Enhanced
Cordless Telecommunications (DECT) protocol.