CNDS

1. CNDS Lecturer: Miss Ponnu Devi • Group Members: • Kok Wai Hien KL003828 • Oon Thiam Teck KL003833 • Lim Cheah Yiing KL003687 • Woon Yen Lin KL003856 • Tan Pei Voon KL003889 • Monica Choy KL003857 • Leong Pui Yee KL003603 ISDN Presentation

2. Objective • To integrate the service network in WAN. • Discuss Future Application and Services that will benefits from broadband. • Discuss Channels of ISDN.

3. Introduction • What is ISDN? • Stands for Integrated Services Digital Network • Is a system of digital phone connections. • Allows data to be transmitted simultaneously across the world -- end-to-end digital connectivity.

4. The combining of voice and data services over the same wires. • Provides a huge improvement in access speed. • It's equally available to home and business customers. • Supports both circuit switching and packet switching.

5. History • Conventional phone system use analogue • Great inefficiency • Prone to breakdown and noise • Did not lend itself well to long-distance connections • In the 1960’s, the telephone system began converting its internal connections to a packet-based, digital switching system.

6. Today, most voice switching in the world is digital. • Recently, ISDN service has been displaced by broadband internet service. • These services are : • faster • less expensive • and easier to set up and maintain than ISDN.

7. Benefits of ISDN : • To the user • cost savings and flexibility. • single access line to all services. • To network providers • support larger potential market for services. • drive down equipment costs.

8. To manufacturers • larger potential market, economies of scales. • standards decrease risk of obsolescence. • To enhanced service providers • simplified user access.

9. Conceptual View

10. ISDN Architecture:

11. All modern switches are able to switch ISDN calls, using ISDN linecards and ISDN featuresoftware. • Digital signal takes place between the customer's terminal and the central office. • Terminal Equipment (TE) -- connected computers, fax machines, LANs, or telephone sets. • TE1 – connect directly through 4 wired twisted pair digital link • TE2 – connect through TA • Terminal Adapter (TA) -- either a stand-alone device or a board inside TE2 • Network Termination 1 (NT1) – physical and electrical termination • Network Termination 2 (NT2) – intelligent devices for switching and concentration

12. Circuit-switched capabilities : 64-kbps • Packet-switching capabilities : as provided by other data networks. • Frame-mode capabilities : supporting frame relay • Common-channel signaling capabilities : used to control the network and provide call management.

13. 2 Generations of ISDN • Narrowband ISDN • Broadband ISDN

14. Bearer-channel (B-channel) : • Carry user "conversations" from a telephone, a computer, a fax. • Carries voice and data at 64 Kbps. • Supports circuit-switched, packet-switched, frame mode and semi permanent connections.

15. Delta-channel (D-channel) : • Carries signaling information to control circuit switched calls on B-channel. • Can be used for a data transmission communication at a lower data rate. • 16Kbps / 64Kbps • Carry low-speed data applications. (e.g., videotex, telemetry)

16. High-speed channel (H-channel) : • Can be used as a single trunk or subdivided by the user. • Fast fax, video, high-speed data, high-quality audio and multiplexed information streams at lower data rates. • 384Kbps(H0), 1536Kbps(H11), 1920 Kbps(H12)

17. There are 2 types of ISDN interfaces: • Basic Rate Interface (BRI) – intended for home use. • Primary Rate Interface (PRI) – intended for business.

18. Basic Rate Interface (BRI) : • Consists of two B-channels for data at 64 Kbps and one D-channel for control and signaling at 16 Kbps (2B + D). • 2 x 64 Kbps + 16 Kbps = 144 Kbps (not including overhead), total 192 Kbps (including 48 Kbps overhead). • Designed to operate using the average local copper pair

19. Basic Rate Interface (BRI) : cont’ • BRI can carry a wide and flexible range of communications. • A single BRI, for example, can carry two simultaneous voice or data conversations

20. Primary Rate Interface (PRI): • Consists of one 64 Kbps D-channel for signaling and 23 B-channels (23B + D). • 23 x 64 Kbps + 64 Kbps = 1.536 Mbps (not including overhead) • In Europe - 2.048 Mbps - either 30 or 31 64Kbps B-channels, or one 64Kbps D-channel - thus 30B+D or 31B+D.

21. Primary Rate Interface (PRI):cont’ • In United States and Japan, consists of 23 64 Kbps B-channels and one 64 Kbps D-channel, or 23B+D with a total bandwidth of 1.544Mbps. • PRI for larger users.

22. Layered ISDN Protocol

23. Conclusion • 3 types of channels : B, D, and H channels • 2 types of ISDN interfaces : BRI and PRI • Benefits of ISDN • 3 layers of protocol in ISDN

24. Q & A • 1)What are the three types of channels in ISDN? • Bearer-channel (B-channel) • Delta-channel (D-channel) • High-speed channel (H-channel)

25. 2) What are the two types of ISDN interfaces? • Basic Rate Interface (BRI) • Primary Rate Interface (PRI) • 3) What is B-channel? • carries circuit switched voice and/or data communications at speeds up to 64 kbps. • Bearer channel -- basic user channel.

26. 4) What are the 3 layers of protocol in ISDN? • Layer 1 - Physical Layer • Layer 2 - Data Link Layer • Layer 3 - Network Layer

27. 5) What are the 2 generations of ISDN? • Narrowband ISDN • Broadband ISDN

28. 6)Who will get the benefits of ISDN? • user • network providers • manufacturers • enhanced service providers

29. Reference • http://www.y-net.gr/hpcn/english/isdn/ • http://www.ralphb.net/ISDN/ • http://www.idstech.com/overview.htm • http://vvv.it.kth.se/edu/gru/Telesys/95P2_Telesystem/HTML/Module10/ISDN+ATM-4.html • http://www.webopedia.com/ • http://www.wikipedia.com/

30. THE END