Presentation on theme: "Broadband Technology Cable modem & DSL Cosc 513 Professor: Dr. Anvari By Ching-Jen Hsueh 106003."— Presentation transcript:
Broadband Technology Cable modem & DSL Cosc 513 Professor: Dr. Anvari By Ching-Jen Hsueh
Broadband Technology Contents I. Introduction II. The Advantages of Dial-up modems III. The Advantages of Broadband Connection IV. Cable Modem V. DSL VI. Security Issues VII. Summary VIII. Reference
Broadband Technology Introduction 1. Broadband Technology A kind of wide-spread, high-speed Internet access 2. Broadband Connections Cable model, DSL (ADSL, SDSL), T1& ISDN, and Satellite
Broadband Technology Advantages of Dial-up modems: 1.Dial-up is cheap and everywhere a. cost free~$30 b. no distance limitation 2. An unwired PC is safer
Broadband Technology Advantages of Broadband Connections: 1. Broadband Internet service is Always-on You dont have to dial in your ISPs server, just lunch your browser and youre there. 2. Broadband Internet service is faster Cable and DSL connections generally deliver an average min of around 150 Kbps and max 1~2 Mbps, versus the max of 53.3 Kbps for dial- up Internet services.
Broadband Technology Disadvantages of Broadband Connections: 1.Broadband does not well spread 2.Security issues 3.Cost
Cable Modem Cable access is the most widely available and most commonly used broadband technology in U.S. Cable Web access is faster than dial-up and less complex to install than DSL Cable modems work via a 6-MHz channel slot with the cable signal to deliver burst download speeds of up to 5 Mbps.
Cable modem Features of Cable Modem: 1.Shared bandwidth 2.Upload speed is lower than download speed 3.Available in residential areas, often not in downtown or commercial areas
DSL( Digital Subscriber Line ) DSL is the second –most-popular broadband service in U.S., trailing cable modem access DSL delivers digital data through phone lines DSL boasts faster connection times, high throughput, and cheaper subscription costs DSL is available in metropolitan areas and their surrounding suburbs.
DSL( Digital Subscriber Line )
ADSL( Asymmetric Digital Subscriber Line ) 1.Asymmetric data transmission Different downstream and upstream 2.The farther the line, the slower the rate 3.You phone line does double duty Use different frequency for voice and data
ADSL( Asymmetric Digital Subscriber Line )
Security of Broadband 1.Always on access means always exposed 2.Hardware protection NAT (Network Address Translation) 3.Software protection Firewall software such as ZoneAlarm pro,Norton Personal Firewall
Broadband Technology Reference 1. Computer Networks 3 rd edition By Andrew S. Tanenbaum