Voice Over IP Overview
VoIP is an emerging technology that allows voice calls to be made over an IP network. Vendors have been pushing VoIP for a few years, but many potential customers have been waiting for “better” call quality, or believe that nothing is free.
If applied and configured correctly, a VoIP solution can provide excellent call quality, and tremendous financial savings to both large and small organizations.
The Key to implementing a successful VoIP solution is to
Identify opportunities that fit.
Do Companies Want VoIP?
76% Will!
76% Will!
Unsure
4%
Not at all
likely
4%
Not very
likely
16%
Likely
28%
Very likely
32%
Extremely
likely
16%
Source: Network World 500/ Progressive
Network World asked 500 readers to assess
Key Business Drivers for LAN-Based Telephony and VoIP
81%
81%
59%
59%
38%
38%
26%
26%
0 50 100 Save Money Save MoneyBetter Utilization of Bandwidth
Better Utilization of Bandwidth
Support Multimedia
Support Multimedia
Improve Network Management
Improve Network Management
Source: Survey by Yankee Group Survey, 10/98
Identifying VoIP Solutions
Customer Specific Questions
-• Does the customer make long distance calls between offices ? • Does the customer have a large, at-home workforce?
• Has the customer already made an existing investment in WAN infrastructure which could be leveraged for a VoIP solution?
• Is the customer looking to set-up a call center?
• Is the customer looking to scale-down communications support costs?
Project Specific Questions –
• Is there enough bandwidth? (if no, how much more is needed?) • Does customer already have required network infrastructure? • What is the ROI on the VoIP project?
VoIP is a simple concept to sell, but answer these questions before hand to determine if the application fits
How does VoIP Work?
1. Compression – voice is compressed typically with one of the following
codecs, G7.11 64k, G7.29AB 8k, G723.1 6.3k
These steps happen in reverse at the other end
2. Encapsulation – the digitized voice is wrapped in an IP packet
3. Routing – the voice packet is routed thru the network to its final destination
Types of VoIP Technologies
1.
IP LAN Telephony or IP PBXs
• By design, an IP based telephone PBX system
• Telephones are IP handsets and codecs in one
• PBX chassis performs call routing and traditional telephony functions • Voce travels over Ethernet computer LAN
• TOP Manufacturers include: Cisco and 3COM / NBX
2. VoIP Gateways
• Devices which allow the bridging of legacy PBX systems and/or analog telephones over IP networks.
IP LAN Telephony or IP PBXs
NBX Chassis NBX Business Telephone Full-featured Ethernet-based telephone NBX Call Processor (NCP) cardNBX Analog or Digital Line Card NBX 10BASE-T Hub Card
NBX Open Platform allows for the use of industry-standard network hubs & switches to connect additional telephone sets
Can be Switched 10 Mbps
IP PBX Architecture
*NBX 100 is Independent of the Network File Server
*NBX 100 System stays up even when the file server goes down.
Network File Server
Hub or switch, 10/100
Sample Application
PSTN Router Layer 2 Switch PBX Main Office SO / HO HUB IP Router or ISDN, DSL LAN Modem IP NetworkSample Application
IP NetworkSmall Office 1
IP Router Hub or Switch NBX 100Small Office 2
IP Router NBX 100 PSTN PSTN Hub or SwitchVoIP Gateways
Allows the bridging of IP and circuit switched telephony devices
Primary Uses of VoIP Gateways
• Toll By-Pass, #1
• Integration of heterogeneous PBX environments over WAN • IP Gateway for Mobility
• Telecommuters, SOHO
TOP Manufacturer VoIP Options
• Cisco, VoIP Card for 2600 series (and up) routers
• Manufacturer Specific Gateways, (Nortel, Lucent, Siemens, etc.) • Ericsson WebSwitch (WebSwitch 100 and 2000)
How VoIP Works
LAN B LAN AGW
router
router
GW
PBX A PBX B EXT 101 EXT 201 IP NetworkEXT 101 places a call to ext 201. PBX A sees ext 201 as the gateway and sends the call out to the GW. The GW compresses the voice and encapsulates it in an IP packet and sends it to the destination of the other GW. The GW on LAN B must strip out the IP, decompress the voice and route it to PBX B.
VoIP Application
PBX Digital Handsets PBX Branch Office #2, TX Digital Handsets Branch Office #1, FL Digital Handsets PBX Main Office, CA FR NetworkFrame Relay Connection
Ericsson Webswitch 2000
• Allows Toll By-Pass via FR Network • Local dial tone at remote office
• 3 digit extension dialing between offices
VoIP Application
Analog Phone Analog FAX WS 100 Analog Phone Analog FAX WS 100 Digital Handsets PBX Main Office, CA PC Telecommuter PC Telecommuter DSLCable connection Internet Webswitch 2000• Toll By-Pass via Internet • Analog phones appear
