1. © 2006 Cisco Systems, Inc. All rights reserved. Optimizing Converged Cisco Networks (ONT) Lesson 1.1: The Evolution of Telephony in the Enterprise

2. © 2006 Cisco Systems, Inc. All rights reserved. Objectives  Describe the history of the telephone services industry and its affect on modern business practices.  Identify the components of the traditional telephone system.  Describe traditional POTS service.  Describe ISDN & T1 services.  Explain the drivers of converged networks.

3. © 2006 Cisco Systems, Inc. All rights reserved. Basic Telephone System  A telephone system has four elements: A telephone set to convert sound to electrical signals and back to sound One or more central switching facilities Connections to the central switching facilities Connections among multiple switching centers across telephone networks  Subscribers connect to the telephone network using: Dedicated wire connections in overhead or underground cables Radio waves (cellular, satellite, or radiotelephone) VoIP

4. © 2006 Cisco Systems, Inc. All rights reserved. Basic Components of a Modern Telephone System Fiber IP POTS and ADSL Central Office with Switches Home Office with Corporate VPN including VoIP Cellular Phone System Long Distance and International Connections Local Loop

5. © 2006 Cisco Systems, Inc. All rights reserved. Traditional POTS Services  PSTN or PTT (POTS) has remained practically unchanged for over 100 years offering: Bi-directional, or full duplex, voice path to carry sound both ways at once Dial tone and ringing signals Subscriber dialing Operator services, such as directory assistance, long distance, and conference calling assistance Power

6. © 2006 Cisco Systems, Inc. All rights reserved.  ISDN: A set of standards that allow data and voice to be carried on copper wire from the telephone exchange to customer premises: BRI: 2 B-channels and 1 D-channel for control PRI: 23 B-channels (30 in Europe) and 1 D-channel for control  T1 Carrier System: Specification for digital transmission between telephone exchanges and sometimes directly to customer premises. T1 uses copper wire or fiber. ISDN and T1 Services

7. © 2006 Cisco Systems, Inc. All rights reserved.  Digital Telephone Services include: Voice mail Caller ID Call waiting Reminder calls (Three-way) conference calling Enhanced 911 (in North America) Centrex A number of other similar services Digital Telephone Services

8. © 2006 Cisco Systems, Inc. All rights reserved.  Centrex (a virtual PBX): Call Transfer Call Divert – on no reply and on busy calls Call Waiting Three-Party Conference Call Pick Up (Group) Ring Back Reminder or Alarm Call Last Number Redial Centrex Hotline (non-dialed connection) Centrex Warm Line (delayed Hotline) Centrex Hunt Groups, with optional bypass numbers Typical Centrex telephone. Note the Recall button and the Message Waiting lamp. PBX and Centrex

9. © 2006 Cisco Systems, Inc. All rights reserved. PBX May I have a line to Chicago? PSTN Is this a business call? Thank you. One second please. Chicago Office Yes it is. Long-Distance Calling Challenges

10. © 2006 Cisco Systems, Inc. All rights reserved.  Long-distance trunk lines connect telephone exchanges.  Long-distance services include: OUT-WATS: Flat-rate long-distance calling IN-WATS: Toll-free calling using 1-8xx numbers Long-Distance and WATS

11. © 2006 Cisco Systems, Inc. All rights reserved.  San Jose Office  Tokyo Office  London Office PBX Separate Voice, Video, and Data Networks

12. © 2006 Cisco Systems, Inc. All rights reserved. IP WANPSTN Converged Voice, Video, and Data Network

13. © 2006 Cisco Systems, Inc. All rights reserved. Self Check 1.What are the 2 levels of ISDN service? 2.What is a Centrex? 3.What is a WATS-type plan? 4.What options are available in WATS plans?

14. © 2006 Cisco Systems, Inc. All rights reserved. Summary  Companies have used telephone services for over 100 years as a part of their business practices.  Changing technology and changing enterprise needs have influenced changes in telephony services.  The increasing use of IP transport for data, voice and video has lead to the need for converged networks.

15. © 2006 Cisco Systems, Inc. All rights reserved. Q and A

16. © 2006 Cisco Systems, Inc. All rights reserved. Resources  Wikipedia Telephone Exchange article http://en.wikipedia.org/wiki/Telephone_exchange  Cisco IP Telephones on Converged Network Enable Rapid Emergency Response http://newsroom.cisco.com/dlls/partners/success_stories/2001/p ss_10-10.html  Making the Business Case for Unified Communications http://www.cisco.com/en/US/netsol/ns340/ns394/ns165/network ing_solutions_audience_business_benefit0900aecd80472efb.ht ml

17. © 2006 Cisco Systems, Inc. All rights reserved.