Format of workshop

1
Format of workshop

• Introduction to computer networks
• Packet
• IP
• How data is transfer on the network (Peter Packet
  website)
• Introduction to VoIP
• Why VoIP is so popular?
• Type of VoIP applications
• VoIP equipments
• VoIP implementation and demonstration
• Conclusion

2
Computer Networks

• Wide Area Networks (WANs) link together sites
  that may be distributed over a large geographic
  area
• Example Staffordshire University network
• Example Metropolitan networks
• Local Area Networks (LANs) link together systems
  within the same site, often the same lab or
  floor.
• There is a variety of (often incompatible)
  hardware and software systems available for
  networking.

3
Computer Networks

• Hubs and routers link systems together.
• Large businesses may have multiple LANs per site,
  interconnected across the country by WANs.
• The Internet is a public network that can join
  WANs and LANs together but privacy is an issue
• Most of the Internet-specific network is
  backbone used to link WAN to WAN.
• Example JANET, superJANET.

4
Information as packets

• Imagine writing a long letter to someone.
• But only having postcards on which to write
• You would write your letter, then send lots of
  individual postcards.
• Each one would need a stamp and an address.
• And you would have to number the postcards.
• What if one postcard failed to arrive?

5
Packet Switching

• Messages are chopped up into small chunks called
  packets before transmission.
• Each packet has an address attached. Each
  packet could be sent via a different route,
  depending on network traffic and available
  routes.
• Packets are received at the destination
  (sometimes out of order) and the message is
  reassembled.

6

• Visit http//www.peterpacket.com

7
Rrrrrring.

• VoIP stands for Voice over Internet Protocol
• VoIP uses computer networks for making telephone
  calls.
• Voice is converted to a digital signal and
  compressed.
• The data is separated into packets, and sent
  instantly over your internet connection.
• The packets are sent over the internet to
  receiver.
• As the packets arrive, similar software
  reassembles the packets, decompresses them into
  sound, and plays it.

8
Rrrrrring.Rrrrring

• VoIP let you make toll-free long distance voice
  over existing data networks instead of public
  switched telephone network (PSTN).
• VoIP solution can dramatically cut long distance
  call charges between two or more locations.

9
VoIP vs circuit networks

• POTS (Plain Old Telephone Systems) used circuit
  switching techniques.
• Only 40-50 bandwidth used.
• Cheaper cost.
• Pay back period is short.

10
Example of VoIP applications

• PC (software) to PC (software) by home users
• PC to phone
• Phone to Phone
• Inter Offices (across national/international)
  Voice Traffic is Toll Free

11
VoIP services

• Skype
• MSN messenger
• Yahoo messenger
• Vonage
• FreeWorldDialup
• Brekeke
• Yourself !

12
Equipments needed

• IP networks/Broadband Internet
• VoIP Server
• PC with VoIP software or VoIP phone
• VoIP adapter

13
VoIP Drawbacks

• Some VoIP services don't work during power
  outages.
• Not all VoIP services connect directly to
  emergency services through 9-1-1.
• VoIP providers may or may not offer directory
  assistance/white page listings.
• Voice data must be a real time stream

14

• VoIP implementation and demonstration

15
Conclusion

• We have discussed the basic of basic of VoIP
  technology.
• VoIP is very, very topical at present (2005)
• It has been around for some time but it seems to
  be appearing as a corporate solution.
• VoIP will be appearing everyday in the near
  future.