Term
| Call Admission Control (CAC) |
|
Definition
A method of preventing oversubscription of VoIP
networks. Unlike QoS tools, CAC is call-aware (not just packet aware) and acts as a preventive congestion
control by attempting to route calls across other media (like PSTN or the internet) before making a determination to block a call rather than impacting the quality of existing calls. In short, CAC prevents users from establishing calls that result in a degradation of quality for existing calls.
. Fully configurable locations, topology, links, and limits
. Preferred interlocation routes for voice and video
. Policy rules by link and media type
. Dynamic enforcement
. Full path assessment at session initiation
. Reroute or fail of call if session exceeds limits (voice can be rerouted to PSTN)
. The capability to use different links for voice and video if desired (for example, a WAN link for voice and direct video over the internet) |
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Term
| Call Detail Records (CDR) |
|
Definition
A record produced by a phone system containing
details of calls that have passed through it. They track information such as the
number of the calling party, the number of the called party, the time of call initia-tion, the duration of the call, the route by which the call was routed, and any fault
condition encountered. These records might be used for cross billing, for tracking of
an employee’s usage of the system, or for monitoring system uptime and issues |
|
|
Term
| Common Intermediate Format (CIF) |
|
Definition
A format used to standardize the vertical
and horizontal resolutions in video signals, often in video conferencing systems. |
|
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Term
| Direct Inward Dialing (DID) |
|
Definition
A service offered by telephone companies wherein
one or more trunk links is provided to a customer for connection to the customer’s
PBX. Incoming calls are routed to internal destination numbers at the PBX. This
enables a company to have significantly more internal lines than it does external
lines |
|
|
Term
| Dual-tone multi-frequency (DTMF) |
|
Definition
A method for providing telecommunication
signaling over analog telephones lines in the voice frequency band. DTMF is also
referred to as Touch Tone. This technology enables users to initiate events in the
phone system by simply pressing a button on a keypad. |
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|
Term
| Extensible Markup Language (XML) |
|
Definition
A set of rules for encoding documents in a
machine-readable format. The goal of XML is to be a simple and open standard for
representing arbitrary data structures, most often in web services. |
|
|
Term
| Extensible Messaging and Presence Protocol (XMPP) |
|
Definition
An open, XML-based
protocol designed to provide near real-time extensible IM and presence information.
It has since expanded into VoIP and file transfer signaling. |
|
|
Term
| Interactive Voice Response (IVR) |
|
Definition
A technology that enables a system to detect
voice and dual-tone multifrequency inputs. IVR is often used in telecommunications
for automated decision trees. This technology powers concepts such as “press 1 for
English” when providing for call routing. |
|
|
Term
|
Definition
In multimedia, MOS provides a numerical indica-tion of the perceived quality of a call after compression and/or transmissions. MOS
is expressed as a single number ranging from 1 to 5 where 1 is the lowest perceived
audio quality and 5 is the highest perceived audio quality. |
|
|
Term
| Private Branch Exchange (PBX) |
|
Definition
A telephone system that serves a particular busi-ness or office as opposed to a common carrier or a system for the general public.
This is what traditionally provides voice services to companies that are connected to
the local exchange to provide external connectivity for telephone calls |
|
|
Term
| Quality of Experience (QoE) |
|
Definition
A subjective measure of a customer’s experiences
with a vendor or service. |
|
|
Term
|
Definition
A mechanism to control resource reservation in a
system; typically, it is a method to prioritize various traffic types to ensure a
minimum level of performance for a particular type of traffic. |
|
|
Term
|
Definition
A standardized packet format for delivering audio and
video over the Internet. RTP’s claim to fame is the capability to deal with large
amounts of packet loss before the impact on the call becomes noticeable |
|
|
Term
| Remote Call Control (RCC) |
|
Definition
A method of utilizing a phone resource on one
system with a resource on another. Typically, in the context of Lync Server, this is
the capability to use a Communicator client to place a call through a desk phone
that is controlled by a PBX rather than by Lync Server. |
|
|
Term
|
Definition
An Internet Engineering Task Force (IETF) defined protocol used for controlling
multimedia communications sessions. The goal of SIP is to provide a common
signaling and call setup protocol for IP-based communications |
|
|
Term
| SIP for Instant Messaging and Presence Leveraging Extensions (SIMPLE) |
|
Definition
An
open standard protocol suite that provides for the registration of presence informa -tion and the receipt of presence status notifications. |
|
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Term
| Survivable Branch Appliance (SBA) |
|
Definition
A combination of Registrar, Mediation
Server, and PSTN gateway that is designed to maintain most voice services for a site
that has lost connectivity to the main Lync Server site. |
|
|
Term
|
Definition
| Standard, Enterprise, and CS Voice CAL |
|
|
Term
|
Definition
Cisco CUCM, Cisco CUPS, and Cisco Unity
IBM SameTime
Avaya Aura
Siemens Open Scape |
|
|
Term
|
Definition
an administrator can take a server offline to
do maintenance on it and it stops taking new connections or calls. Assuming at least one
other server exists in the pool, the end users do not suffer any loss of service. When the
existing connections on the draining server are ended, the system can truly go offline and
any necessary maintenance can begin. |
|
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Term
| Communications Server Sites |
|
Definition
a set of well-connected computers
on a network that contains one or more Lync Server components. Does not necessarily map to AD sites. Defined as either a central site or a branch office site. A central site must contain at least one front-end pool or standard edition server. Branch sites will often contain only a survivable branch appliance |
|
|
Term
| A/V Conferencing Server Role |
|
Definition
| New in Lync 2010 as a separate role fron the Front End Server. Separate off this role for sites with more than 10,000 users and form an A/V Conferencing Pool. |
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|
Term
| Location Information Server (LIS) |
|
Definition
This enables one to base location on subnet, switch, port, or Wi-Fi AP, and those locations
are updated on each client registration or network change. Part of enabling E911 services for Lync. If a user is in the office the location is retrieved automatically. If the client is outside a controlled environment, the client might prompt the user for location based on a policy created by the administrator. A user can select location info. from previously entered locations. If no location info is available for a user, E911 services are not available. |
|
|
Term
|
Definition
In Lync Server, the flow of media traffic can be configured to potentially bypass the
Mediation Server. The advantage of doing this is that service quality improves by reducing
unnecessary transcoding, packet loss, and latency when the Mediation server can be skipped.
This functionality can also potentially reduce bandwidth used in cases in which a
Mediation Server and a PSTN gateway (or PBX) are at different sites. By bypassing media
processing by the Mediation Server, call scalability can be improved because one simply
doesn’t tie up resources that aren’t needed. |
|
|
Term
|
Definition
All versions of Communications Server require dial strings to be normalized to the E.164 format. This is necessary for performing reverse number lookups (RNL). Often, down -stream components such as PBXs, SIP trunks, or gateways require numbers in local dialing
formation. It is sometimes necessary to modify downstream components or even reroute calls to accept the E.164 dial string. |
|
|
Term
|
Definition
Response groups are a way to allow multiple endpoints to receive a call to a single entity. Features in Lync:
- Anonymous call handling
- Attendant routing method
- Integrated manageability
- Web Services |
|
|
Term
|
Definition
The Announcement Application in Lync Server enables an administrator to configure how
a phone call is handled if a dialed number is valid but not assigned to a user or common
area. Options include transferring these types of calls to a predetermined destination or to
play a recorded message or both. This avoids the situation in which a caller misdials and
simply hears a busy tone, resulting in a confused caller |
|
|
Term
|
Definition
Translates between Enterprise Voice infrastructure and a basic media gateway. Mediation Server cannot coexist with Lync Web Access, SE
Server, Edge Server, or Enterprise Edition Front End Server |
|
|
Term
| What are the 5 lync roles? |
|
Definition
| Monitoring, Archiving, Front End, Mediation, and Director |
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