Glossary of Terms

Auto Attendant
An automated system that directs incoming calls to the appropriate extensions.

ATM
Asynchronous Transfer Mode. This is a protocol used for high speed data connections

BGP
Border Gateway Protocol. Standardized exterior gateway protocol allowing exchange routing information among autonomous systems (AS) on the Internet. silhouette routers are configured to use BGP, but it is not a requirement.

BLF
Busy Lamp Field

BST
Basic SIP Terminal. Basic SIP terminal (BST) phones have limited functionality and work with a subset of silhouette’s features.

CallP Server
Call Processing Server. This is a piece of software that provides much of the intelligence for the silhouette system

Class of Service
An identifier that indicates a type of telephone call. Examples of Class of Service include "Emergency (911)", "Internal", and "Long Distance".

Click-to-Call
A web-based communication, where a user clicks a button to call a device

Conference Server
A device on the network used to provide conferencing services such as n-way calling. This is also called the Bridge Server.

Customer
From the Service Provider's perspective, this is often used to mean tenant

DHCP
Dynamic Host Control Protocol. This allows devices on an IP network to be dynamically allocated their IP Addresses and other information

DHCP Server
The machine on an IP network which allocates IP addresses and other information to devices on the network.

Dial Plan
A set of entries, which describe what action, the system should take based on the initial digits dialed (such as external call for "9")

DID
Direct Inward Dialing number

DSL
Digital Subscriber Loop. This is a digital connection to a subscriber (usually high speed).

DSLAM
Digital Subscriber Loop Access Multiplexor. This is the device that multiplexes a set of DSL lines together.

EFK
Enhanced Feature Key. The Poly equivalent of the MiNET PMK.

EST
Enhanced SIP Terminal. Enhanced SIP terminal (EST) phones have more functionality than BST phones, and work with all or most of the silhouette system’s features. For example, EST phones can be provisioned with programmable keys.

FTP
File Transfer Protocol. This is a protocol to allow transfer of files (such as the software loads for IP phones) over a network.

FXO
Foreign Exchange Office. The port on an analog device that connects it to the silhouette system through an FXS device.

FXS
Foreign Exchange Service. Interface (port) on an adaptor/gateway device that connects an analog device to the silhouette system.

Gateway
The device connecting the IP LAN to the public telephone network. The gateway contains slots that contain ports that connect to the public telephone network over PRI groups.

GEO
Geo-Redundancy.

Hypervisor
Computer hardware/firmware/software that creates and runs virtual machines; example is VMware ESXi.

ICMP
Internet Control Messaging Protocol. This is a protocol that allows the Ping command.

MBG
Mitel Border Gateway / MiVoice Border Gateway. A border device which provides remote MiNET access for IP phones on the silhouette system.

Media server
A device used to store and play Auto Attendant greetings, announcements and prompts for users of the silhouette system.

MIB
Management Information Base. This is a logical database made up of configuration, status and statistical information. It is transmitted using the SNMP protocol.

MiNET
A Mitel-specific stimulus protocol. Used for Mitel IP phones.

NAT
Network Address Translation. Allows a remapping of an IP address space into another by modifying network address information in the IP header of packets while they are in transit across a router.

NMS
Network Management System (or Station). This is a system used to remotely monitor all components of a network. The most common protocol used by an NMS to communicate with its network components is SNMP.

NOC
Network Operations Center. This is typically a location where the Service Provider's NMS is running.

NPA
Numbering Plan Area. This is a 3-digit code also known as the Area Code

PRI
Primary Rate ISDN. This is a service that provides 23 digital voice channels plus 1 signaling channel on a standard T1 interface in a telephone network.

PKM
Programmable Key Module. A module added to a silhouette IP phone that provides additional PMKs.

PMK
Programmable Memory Key

PRI Group
A grouping of PRI channels used for routing information.

Product DHCP Server
The DHCP Server provided as part of the silhouette product

PSAP
Public Safety Answering Point. A facility equipped and staffed to receive 911 calls

PSTN
Public Switched Telephone Network.

PVC
Private Virtual Circuit. This is a reserved part of an ATM connection.

RFC
Request For Comments. This is actually used to describe specifications for protocols and computer industry related issues that are now considered standard. For example, the standard definition of SNMP is referred to as RFC1157

Route
A logical entity used to describe the type of calls based on dial plan (such as Internal, Long Distance, and so forth)

Route Entry
An entity that describes to which PRI group a call should be routed

RTCP
Real Time Protocol. This is a protocol used for sending messages to and from the IP Telephones.

SBC
Session Border Controller. A border device which provides access for IP phones on SIP platforms.

SIP
Session Initiation Protocol. Protocol used by user agents (BST and EST phones) and by user agent servers like silhouette.

Service Provider
This is a company that purchases the silhouette solution and sells voice over IP telephone service to tenants; aka Telco

Slot (on a gateway)
A single interface on a gateway. The slot contains ports that connect to PRI groups.

SMDI
Simplified Message Desk Interface. This is a protocol used to communicate with a voicemail system.

SMDI Port
A number indicating a characteristic of IP messages for the voice mail system.

SMDR
Station Message Detail Recording. Captures detailed information about incoming and outgoing voice and data calls.

SME
Small and Medium Business Enterprises

SMTP
Simple Mail Transfer Protocol. This is a protocol for sending e mail messages.

SNMP
Simple Network Management Protocol

T1
A standard North American physical wiring interface which provides twenty four 64 kilobit/second channels for telephone calls.

TCP
Transmission Control Protocol. This is a layer added onto the IP protocol (shown as TCP/IP) to provide reliable communication.

Telco
Telephone Company. This is a company that purchases the silhouette solution and sells voice over IP telephone service to tenants; aka Service Provider

Tenant
A customer of the Service Provider.

Tenant Administrator
A user id that has the access rights required to perform administrative functions for a given tenant.

TFTP
Trivial File Transfer Protocol. This is the protocol used by the silhouette TFTP Server that sends the software load files to IP phones.

UBR
Unspecified Bit Rate. This is a characteristic of a PVC in an ATM connection. In the silhouette system, it would be used for PC data traffic.

UDP
User Datagram Protocol. This is a layer added onto the IP protocol (shown as UDP/IP) to provide a simple way to deliver information.

User
An individual with access to the web interface of the silhouette product. A user has an associated user id and password/PIN number. From the perspective of a tenant, a user also has an associated telephone extension

VBR rt
Variable Bit Rate Real Time. This is a characteristic of a PVC in an ATM connection. In the silhouette system, it would be used for telephony traffic

VCI
Virtual Circuit Identifier. This is part of the definition of a PVC in an ATM connection. A PVC is uniquely identified by its VCI and VPI (usually written in the form ccc.ppp where ccc is the VCI and ppp is the VPI).

vCenter
The VMware centralized management utility. All silhouette virtual machines are configured in vCenter.

VM
Virtual Machine. An emulation of a computer system, created and managed by a hypervisor, providing the functionality of a physical computer.

VPI
Virtual Path Identifier. This is part of the definition of a PVC in an ATM connection. A PVC is uniquely identified by its VCI and VPI (usually written in the form ccc.ppp where ccc is the VCI and ppp is the VPI).

Voicemail system
A device used for storage and retrieval of subscriber's voicemail.

VRA
Zerto Virtual Replication Appliance. A Zerto VM that manages the replication of silhouette VMs across sites; must be installed on every host that manages VMs that require protecting in the Primary (protected) site and on every host that manages virtual machines in the Standby (recovery) site.

VRF
Virtual Routing and Forwarding. Allows multiple instances of a routing table to co-exist within the same router, concurrently.

VRRP
Virtual Router Redundancy Protocol. Allows automatic assignment of available routers to participating hosts.

Zone
A logical entity that associates sites with dial plans and CallP servers. Zones contain route entries that determine the physical routing of outgoing calls from the system.

ZVM
Zerto Virtual Manager. Central management interface for Zerto replication and recovery, deployed in a VM, 1 per vCenter.

Zerto Virtual Protection Group
A logical grouping of virtual machines and virtual routers (within a network container) within a data center that are replicated to a standby Zerto Virtual Protection Group contained in a standby data center.


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