Phones and Telephony

Tools and Tricks with phones and telephony.

Sound: “You have 937 messages, all of which are marked Urgent”

“No, I don't know his telephone number. But it was up in the high numbers.” —Attributed to the father of modern macroeconomics, John Maynard Keynes

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Phone Words to Numbers

Alphanumeric #:
Converted:

10 Letters or More

Letters can be longer than 10 characers of a phone number because even though more can typed in, in the U.S., only the first 10 digit dialed (after the 1 if input) is recognized by phone companies. Other countries may use a different number of digits.

# International Dialing

When dialing internationally, after pushing the last digit of the number you want, push the # (“pound”) key (at the lower right). This makes the call go through faster because the system now knows it has all the digits and doesn't have to wait to see if more are coming.

PSTN

The telephone system is called the PSTN (Public Switched Telephone Network). It is described as a connection-oriented circuit-switching network because a connection is dedicated for the entire duration of every .call.. The system establishes a physical electronic circuit for each caller and maintains (consumes/hogs) it regardless of the amount of talking going on (how much of the bandwidth is being used). This is for the convenience of teenagers calling friends to figure out their homework. ;-) Anyway, we are told to refrain from making calls immediately after an earthquake or other public emergency because, at any given time, the PSTN can handle an albeit large but yet limited (fixed/finite) number of connections.

old phone ringing
phones ring at the same time
phone destination busy
phone trunk busy
fax answering sound
analog modem connection

Leave a Message on Cell Phones without Ringing

• SlyDial has figured out a way to put a voice message directly into someone's cell phone voicemail without ringing first. And the situations why this is useful is hilarious.

Appease your family Your Aunt June sent you a sweater for your birthday. You need to call her to thank her but you don't want to listen to her go on and on about her recent hip replacement. Instead just leave her an appreciative voicemail that she can share with her bridge club.

Create the illusion of communication You maxed out your emergency credit card the first week of school. Your parents are looking for some answers. A text message isn't going to cut it but a voicemail would mean that you tried calling them.

Phone Costs

Here is what I've found so far about getting the best phone service for my money.

Internet (Voice Over IP) PC to Phone Calling

To use your regular phone/fax with a broadband DSL or cable service, plug it in a Motorola VT1000 (or Cisco ATA-186) analog to digital phone converter provisioned by Vonage or . Voice Pulse (which supports both SIP and IAX). Vonage charges about $30 per month for unlimited calling to any area code of your choice (including Canada). This does not require your computer to be running all the time. But you will have to register your 911. forum.

The real-time multimedia communications and processing standard — International Telecommunications Union (ITU) H.323 — as implemented on Cisco and Microsoft's Internet Security and Acceleration Server 2000 requires a patch to close the vulnerability which could allow an attacker to take control of the system

To use your computer to make voice calls over internet lines, you need microphones (and cameras) on your computer and a VoIP service:

Microsoft's NetMeeting, which includes video, was phased out in favor of Microsoft's Windows Messenger. Download mmssetup.exe which invokes msmsgsin.exe which installs the msmsgs.exe application program. Meeting by wire.com covers this in detail. Only the Windows XP version of Windows Messenger does video.

Net2Phone charges 2 cent per minute for PC-to-phone calls or 3.9 cents for calling card calls with no connection charges.
Deltathree charges 1.2 cent per minute for PC-to-phone calls or 5.9 cents for calling card calls with no connection charges.
PhoneFree charges 2 cents per minute. Download and install the PhoneFreeSetup.exe, which invokes setup_pf.exe which installs PhoneFree.exe. But beware that your firewall may block its use of HTTP on port 8000 and Standard FTP (PASV mode) on port 21 for voice mail and icon uploads from cgi1.phonefree.com. For ITU H.323 Compliant V2oIP Multipoint peer-to-peer voice conversations, PhoneFree uses TCP 1035 and UDP 1034. The PhoneFree Personal Communications Center (PCC) Gatekeeper uses TCP 2644.

Freeworldialup (FWD) by VoIP guru Jeff Pulver assigns a 6 digit to 26 digit "FWD" number for free VoIP calls among 80,000+ members using SIP phones.

Multi-Way Teleconference Calling

Conference calls (where several people can talk at the same time) can be very expensive when arranged by major carriers such as AT&T, SBC or MCI.

You can arrange for 3-way call capability on your local line for a monthly fee.

• EarthConference.com of Tracy, CA (a division of TerraGold.com that contribute 20% of proceeds to environmental groups), provides up to 10-way calling for families at $30 per month or 12 cents per minute. Businesses pay $50 per month or 12 cents/minute to a 620 number (19/min. for 800 number with no operator). Call 877.248-1379 with code 216793. For info: 888.665-5900 Fax: 713.780-5931

  It's 25 cents per minute for a 713 number where an operator calls participants.

Slamming

Who really is your carrier? From Slamming

To verify who is your long distance carrier, call 611 or the customer service number for your local carrier (SBC (PacBell), Verizon (GTE), etc.). Ask for the toll-free number to call for carrier verification. Usually it's 700-4141 for local toll service and 1-700-555-4141 for long distance. An automated voice will say “Welcome to ATT”.

This aggressiveness is the result of a court consent degree which forced AT&T to

1. spin off operating companies offering local service into separate companies, and
2. open up long distance lines to competitors such as Sprint and MCI (which later merged into Worldcom)

On September 20, 1995, AT&T began restructuring its systems and equipment business (Bell Laboratories) into Lucent Technologies and its computer systems business into NCR.

AT&T Broadband was formed.

ISDN

The Integrated Services Digital Network (ISDN) spec is designed to give homes Dial-on-Demand (DDR) dial-up service to businesses offering voice, data, and imaging. ISDN uses the same copper telephone wires as PSTN, but with digital instead of analog modems. ISDN is a switched service, not a continuous-on service like T1 or broadband cable nor a bandwidth-on-demand service like frame relay. Sending signals digitally is faster and more reliable because it eliminates the delays from the conversion of signals between analog audio and digital formats that slow transmissions and causes disconnections. PPP Multilink that has a special sequence field to ensure that packets do not reach the destination out of sequence

The different formats of ISDN service each split bandwidth into several channels:

• Basic Rate ISDN (BRI), also called 2B+D, splits 144Kbs of bandwidth into 3 channels: Two B (bearer) channels carry data at 64 Kbps for a combined 128 Kbps data transfer speed. Compression can increase thruput. A third D channel transmits carries signaling and link management data at 16 Kbps.

• Primary Rate ISDN (PRI), also called 23B+D (30B+D in Europe), splits the 1.544Mbps bandwidth from the 24 bands of a T1 link: a D channel for signaling and link management uses 64 Kbps, plus 23 B channels at 64 Kbps each. The 2.048Mbps transfer rate uses 30 B channels over a T2 line.

ISDN D channels use “out-of-band” signaling, where frequencies used for transmitting control and management signals are outside the band used for data payload transfer. Unlike previous methods (which used one frequency for all transmissions), ISDN can monitor data and control line conditions separately.

Cisco router commands

To enter the unique SPID number for each ISDN channel, use this Global configuration command:

isdn spid[spid channel designation] [SPID #]

To enter the ISDN switch type a router is connected to, use this Global configuration command:

isdn switch type basic-[switch identifier]

VoIP (Voice over IP lines)

Each incoming line can support about 5 phones ringing (each with a Ringer Equivalency Number of 1.0)

Vonage

Voice Pulse

How to install VoIP