Transcript Voice over Internet Protocol (VoIP)

Voice over
Internet Protocol
(VoIP)
Agenda
1. Terms and Definitions
2. How Does it Work
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packet switching vs. circuit switching
what is needed by user
challenges
3. Benefits to small and medium sized
Businesses
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convenience
pricing
4. Projections for the Future
Terms
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DID Direct Inward Dial ( a phone number)
ITSP Internet Telephone Service Provider (Vonage, Binary Telecom)
PSTN - Public Switched Telephone Network
POTS - Plain Old Telephone Service (individual lines)
ILEC or LEC (Incumbent Local Exchange Carrier) Qwest/Verizon
CLEC (Competitive Local Exchange Carrier) Integra, XO
SIP (Session Initiation Protocol) Signaling that starts the communication process
between nodes; RTP (Real Time Protocol) to transmit the audio.
SIP Trunks - An Oxymoron because SIP allows multiple simultaneous calls on one
DID. Occasionally used to compare “lines” with T-1 Channels or POTS Lines. No
more guessing at the right number of “outside lines” available.
E911 – Enhanced 911 – provides a screen-pop at the Public Safety Access Point
(PSAP) of caller’s location.
QoS (Quality of Service) Routing priority for voice over other ordinary data on the
networks. Newer routers from Cisco, Linksys and D-Link support QoS.
G711 Codec– 64 kbps (plus overhead) per call. Same as POTS
G729 Codec – 8.5 kbps per call. Sound quality of a cell-phone.
LNP (Local Number Portability) One of the charges you pay each month for the
privilege of being able to move your number to another carrier.
VoIP
Definition
(Wikipedia) A Protocol for the transmission
of voice through the Internet or other
packet switched networks, including your
own Local Area Network (LAN) and Wide
Area Network (WAN).
Circuit
Switching
(Wikipedia) A fixed bandwidth circuit (or channel)
between nodes so the users may communicate, as if the
nodes were physically connected with an electrical
circuit.
Packet
Switching
• Same routing system used by a computer to
send and receive data (IP).
• Audio is divided into data-blocks (packets)
– Each data packet has a header that identifies an IP
address to which it will go.
– The route can be random; determined by speed, cost,
or peering among networks and service providers.
– Packets arrive, are reassembled in the proper order.
• More efficient, allows more simultaneous calls to
be made.
Benefits
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Efficiencies reflected in pricing.
– Free if between Internet connections (Skype, other on-net calling).
– $29.95 per month for a business line that includes all Centrex features,
compared with approximately $77 (plus LD) from Qwest/Verizon/AT&T.
– Spreadsheet for comparing rates at: www.binarytelecom.com/costcompare.htm
– Fewer taxes and surcharges.
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Convergence of networks.
– Merging IT and Telephony departments.
– No more costly service for Moves/Adds/and Changes.
– More options for handsets.
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Online access to call detail 24x7. www.binarytelecom.com
Create a virtual office by using an additional number in another area code. It
rings into your main office and is a local call to your remote customers.
Cordless Wi-Fi enabled IP phones allow freedom of movement
Travelers can use a softphone on a laptop when out of the office.
Hosted
PBX
• Makes your PBX an outsourced Managed Service to an
ITSP in a local tier-one data center.
– supported with redundant fiber connections to the Internet,
generator back-up, and more network security
• Allows most of the features on an expensive PBX or
Centrex service
– Auto-attendant, voicemail, call transfers, music on hold.
– Helps a small business create the impression it is a larger..
• No Licenses or depreciation
• No Maintenance Agreements
• More telephone options for expansion
What is
Needed
• Any analog phone with the addition of an
Analog Telephone Adapter (ATA) or
Gateway device to connect an analog PBX
• Or IP phones made for VoIP
• Or IP enabled PBX
• Broadband Internet access
Challenges
• Client-side ISP Services are the number one hurdle to successful
VoIP experiences.
– Inadequate upstream bandwidth
• Filtered, over-subscribed or without QoS.
– Latency, Jitter & Packet Loss
• Frequent very brief interruptions (Jitter or Packet Loss), or calls that have a
delay (Latency).
• Mean Opinion Score (MOS) Test at www.testyourvoip.com
• E911 address updates essential.
• Older fax machines don’t play nice with VoIP.
– ITSP needs T-38 Protocol.
– Machine converts a digital image to analog and back to digital. Dropped
packets will interrupt transmission, and fail.
– Keep a POTS line for faxes and emergencies. Strip it of all features to
keep costs down.
Future
– Market research firm In-Stat in 2006: Market for hosted VoIP
services to grow 10-fold, to $1.27 billion by 2009, and by the end
of this year, there will be approximately 3.9 million VoIP lines in
the U.S. 2008 -16 million per TeleGeography Research.
– Since 2005, the RBOCs--AT&T, Verizon and Qwest--have lost
over 17 million residential telephone lines to VoIP and Cell
service
– Rapid Growth of IP PBXs
• Asterisk – handles data packets very well.
– TrixBox and other manufacturers of IP PBXs now including this
open source, Linux based, IP PBX (Linksys SPA 9000).
• Mitel, ShoreTel, NEC, Toshiba, GrandStream, Cisco, Allworx
Adtran, Astra and AltiGen.
• Microsoft/Windows.
– 3CX, MS Microsoft's OCS and Response Point phone system
for small businesses.
Summary
• Voip will provide:
– Lower Costs
– More flexibility
– More personal control
• Minimum need for new equipment
• Works great with any GOOD Internet
access
Links
• http://www.testyourvoip.com/ This is a
valuable tool that will assist with evaluating
a network for ample bandwidth.
• http://www.binarytelecom.com/costcompar
e.htm