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V.O.I.P. Voice on Internet Protocol By Matthew Bulat M.Eng.Tech MCSE MCDBA BOCP. What is VOIP?. Routing of voice conversations over the Internet or through any other IP-based network. . Why use VOIP?. Cheaper telecommunications Less phone line rental Less wiring required
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V.O.I.P Voice on Internet Protocol By Matthew Bulat M.Eng.Tech MCSE MCDBA BOCP
What is VOIP? • Routing of voice conversations over the Internet or through any other IP-based network.
Why use VOIP? • Cheaper telecommunications • Less phone line rental • Less wiring required • “Free” phone calls in some situations • Video conferencing possibilities • Branch offices may not need a PABX • Use Wifi bridges to connect phone system
VOIP status now • IP capable PBX becoming dominant • Skype have over 100 million users • VOIP service market increasing 62% / year • IDC Australia predicts that by 2009 there could be as many as half a million retail VOIP users in Australia • Ideal Electrical has VOIP enabled PBX • SA Government has VOIP enabled PBX • New Zealand Govt. had VOIP enabled PBX
What do I need for VOIP? • A network connection LAN/WAN/Internet • Spare network bandwidth for VOIP call traffic • Quality of Service to give priority to voice traffic • Soft Phone software with headset or • Broadband Router with phone socket + phone or • Router + Analog Telephone Adapter + phone or • PABX with VOIP facilities • Wifi Router + Wifi phone handsets
When can I consider VOIP? • When moving to a new building • When STD calls and International calls costs need to be reduced • When line rental fees need review • When new EFTPOS, fax, modems need to be added • If call count per month is high
Disadvantages of VOIP • Quality of calls across Internet is not assured • Broadband equivalent connection needed for connecting offsite • Network switches may need replacement • Power on Ethernet may need to be established over the LAN • Phone availability is dependant on network hardware and power • Some VOIP providers have fees • Emergency calls 000 do not issue an origin
VOIP Alternatives • Call cap plans with Telecommunications provider • Virtual fax lines that get sent to email • ISDN D channel for EFTPOS • Advanced forms of Instant messaging • Use mobile phones and reduce land lines • Least cost routing with various carrier prefixes
Soft Phone e.g. Skype • Free software • Free Skype to Skype • Free Video Conferencing • Prepay to call real phones • Prepay for phone no. (10 Euro for 3 months) • Voicemail with phone no. • Send SMS from PC (has fee) • Can use wherever on broadband • Can work with Pocket PC wifi
VOIP with real phone e.g. Engin • Analog Telephone Adapter $199 with phone socket • Phone number $9.95 per month • 10 cent local and national calls un-timed • Can receive landline and VOIP line to 1 phone • Can fallback to landline if power/network fails
VOIP from router • Use standard phones connected directly to router • Cheaper than router + analog telephone adapter • Quality of service provided at the router
Hybrid PABX inc. VOIP • Adding hardware to existing PABX can gain VOIP between sites while leaving the office architecture the same • Calls can fallback to landlines if WAN is at capacity • VOIP can present itself as a PSTN line to the PABX for traditional use • Least Cost Routing can divert certain calls to VOIP system lines
Sample Large VOIP PABX features • Up to 6000 extensions controlled by 2 RU device • Whole configuration is held in PC-card storage card which can be programmed offsite • Browser can be used to adjust configuration • Wireless LAN handsets
Soft phone PABX Extension Virtual Private Network compatible
Microsoft Office Communicator 2005 • Talk, video conference, chat, whiteboard from PC and phone • Know current status of who you want to contact e.g.. At desk, away, on phone, in meeting, not logged in • Pop up when call comes in with caller details • Dial, transfer call from Outlook type list on PC • Missed calls can show up as a email, click to call back • Divert to a mobile when logged off PC
Office VOIP wiring • One Cat-5 lead for phone and computer (1/2 cables) • PABX , network switch and Power on Ethernet need a good UPS. • Analog devices like faxes/modems need analog adapters • Branch to branch calls have no telephony fees
VOIP Management • Using the LAN/WAN program phone systems across the Enterprise • Better GUI interfaces to control 100’s of possible features • Handset movements in the network keep there extension number as they go. • Web server interfaces for programming at different access levels possible
VOIP specs • Clear voice communications can be had using 64kb bandwidth (both ways). E.g. G711 codec (~28 MB / hour) • With extra compression and processing time voice communication can get by with 8kb bandwidth. E.g. G729 codec (~3.6 MB / hour)
Security • Maintain firewalls, anti virus, security patches, review logs, review activity • Select software that needs a minimum number of ports open. • Direct certain ports to defined IP addresses to handle the traffic. • Define what applications can use a port. • Encrypt voice signals and protocols used • IP handset MAC address permissions given by PABX • Wifi SSID, WEP/WPA, MAC address filtering • Secure VPN connections
New possibilities for telephony • PABX – LAN ~ Wifi Bridge ~ LAN – computers and phones • No phone system needed in second building • No cabling required across roads, common land etc.
Remote Telephony • Work from home using computer as a phone extension from work. • Work at multiple branches where your computer keeps its extension number as you move.
The Future • Mobile phone that can do Wifi VOIP if in range • VOIP using Wimax (no phone lines required) • Internet / VOIP / Video on demand broadband • ISP’s working like carriers with Quality of Service for VOIP on their network • Wireless phones with Skype built in (2006 Q3)
Resources • www.phonechoice.com.au (includes calculator for plans based on your current usage) • www.OzInternetPhones.com.au (list providers) • http://www.erlang.com/calculator/lipb/ (voice paths to VOIP bandwidth calculator • www.voipnews.com.au • http://www.avoipa.org.au/ Aust. Comm. Industry Forum • http://www.acma.gov.au Aust. Comm. & Media Authority