Please explain the asterisk features listed here

here are the few features for which i have written the explanation and some which i cant understand well
please explain them

hope i may be able to post all features at

Feature : Explanation
call features

[list]ADSI On-Screen Menu System : ?

Alarm Receiver : recieve a alarm on your phone

Append Message: append message onm the mailbox

Blacklists: Screening malacious user

Blind Transfer: Blindly transfers a call

Call Monitoring: used in ACD but but how?

Call Parking: Transgering call to other extension by any user

Call Queuing: Quing up the call

Call Recording: recording the conversation

Call Retrieval:?

Call Snooping:?

Call Transfer: transfering the call to other extension

Call Waiting:?

Calling Cards:?

Conference Bridging:?

Database Store / Retrieve:?

Database Integration:?

Dial by Name:?

Direct Inward System Access:?

Distinctive Ring: The called phone has distinct ring based on the place from where call originated eg within PBX or Outside

Distributed Universal Number Discovery (DUNDi™) : ?

Do Not Disturb: no call will be entertained

E911:enchanced 911 important in case of VoIP solution

ENUM: universal number for your VoIP phone

Fax Transmit and Receive (3rd Party OSS Package) : ?

Flexible Extension Logic:?

Interactive Directory Listing:?

Local and Remote Call Agents: the people can log on to the PBX system
from any phone using a Login ID and hence can recieve and respond to the calls


Predictive Dialer:?


Open Settlement Protocol (OSP) : ?

Overhead Paging:?

Protocol Conversion:?

Remote Office Support:?

Roaming Extensions:?

SMS Messaging:?

Spell / Say:?

Streaming Media Access:?

Supervised Transfer: trnsfering call supervised by some operator

Talk Detection:?

Text-to-Speech (via Festival) : ?

Three-way Calling: adding the third party in the conversation progressing
b/w to prties

Timand Date:?



VoIP Gateways:?

Voicemail to email:?

Voicemail Groups:?

Web Voicemail Interface:?


I don’t have a lot of time, today, but I’ll put my money where my mouth is, as the saying goes - here’s some more for you…

Call Retrieval - goes with call parking, your definition is a little murky; Call Park allows you to place a call on hold on an extension other than your own. This is useful for retail stores or factory floors, where you may need to page for the correct person to pick up the call, which is called Call Retrieval.

Call Waiting - allows the use of a hook-flash to change between two simultaneous calls

Dial By Name - assuming voicemail is set up correctly, Dial By Name allows an outside caller to get 411-like help in finding the extension number of the person they wish to call

Direct Inward System Access (DISA) - allows an outside caller to have full access to PBX functions, which is normally reserved for internal-only access. Common use of DISA is if you have road warriors or home-based workers: they can call into your PBX and make free outbound long distance calls, also appearing to be at your physical location

Distinctive Ring - Asterisk can allow you to change the ring frequency (and sometimes tones) usually based on CallerID of the incoming call, but can be set based on other variables. Useful for call-screening, among other things

Macros - In configuring the dial plan, the use of macros and pattern matching greatly simplifies identical configuration for hundreds, even thousands, of extensions.

Predictive Dialer - generally for use in outbound telesales or customer service; predictive dialing optimizes the time that agents spend on the phone by pre-dialing numbers when it is determined that an agent will be coming available.

Overhead paging - sometimes also called intercom, this allows a centrally-located speaker to be “dialed into,” for making announcements. Frequently seen in retail stores, also car dealers, factory floors and other non-office type situations

Protocol Conversion - can bridge calls between dissimilar systems, for example IAX to SIP, PSTN to MGCP

Spell / Say - can “read” letters and numbers to a caller, for example reading back the current time

Streaming media access - especially because of Asterisk’s open nature, you can stream certain types of media, for example mp3 music, directly into the phone system. Useful for “live” hold messages, et al.

Supervised Transfer - similar to blind transfer, allows a person to transfer a call to another extension by first announcing that call to the transfered extension. Useful in situations like “I have Joe Carseller on the phone, do you want to talk to him?”

Talk Detection - there are a few modules which allow various types of noise detection on certain channels; talk detection can be used to trigger an event, for example, play an automated message when somebody says “hello.”

Text-To-Speech - using the Festival voice synthesis suite, the PBX can read text, for example a web page containing the current weather or an email

Time and Date - unclear; some of the voice protocols (including, I believe, T1/E1 services) allow time sync between various terminations. Voicemail is automatically timestamped, and the system will read back the envelope, which includes time and date (optional). Also, see Text-To-Speech and Say/Spell, above.

Transcoding - This refers to the ability of Asterisk to bridge calls that use different audio encodings, for example g711.u to GSM

Trunking - logically grouping together multiple phone lines for outbound dialing; typically seen in medium to large deployments, the PBX can be configured to auto-select an available line for outbound dialing, rather than the user having to choose which line to dial out on.

VoIP Gateways - Asterisk can act as a bridge between VoIP telephones and the PSTN; additionally, Asterisk can be used to route calls to some third-party VoIP gateways (think Vonage, though I don’t believe that is an available option). Check out BroadVoice or Packet8.

Voicemail to email - Asterisk’s native voicemail can send an email to the voicemail recipient, and can optionally attach a WAV file of the entire message.

Web Voicemail Interface - as with most things Asterisk, it is almost trivial to provide a browser-based interface to the system

Zapateller - built-in, automated “black hole” for inbound telemarketing calls

OSP is a protocol standard for securely routing and accounting for inter-domain VoIP calls. OSP is not a VoIP protocol, but rather a standard for managing the billable exchange of VoIP sessions between IP networks. OSP is used by wholesale VoIP carriers to establish secure point to point peering between source and destination networks. The details for OSP, officially known as “ETSI TS 101 321 Open Settlement Protocol (OSP) for Inter-Domain pricing, authorization and usage exchange”, can be found at

posted the definitionds at … k+Features
please add as many explanations as possible


The Asterisk wiki explains all of that, and more.