• Chapter 1: Describing Network Requirements
• Chapter 2: Topologies for Teleworker Connectivity
• Chapter 3: Using Cable to Connect to a Central Site
• Chapter 4: Using DSL to Connect to a Central Site
• Chapter 5: Configuring DSL Access with PPPoE
• Chapter 6: Configuring DSL Access with PPPoA
• Chapter 7: DSL Connection Troubleshooting
• Chapter 8: The MPLS Conceptual Model
• Chapter 9: MPLS Architecture
• Chapter 10: Configuring Frame Mode MPLS
• Chapter 11: MPLS VPN Technologies
• Chapter 12: IPsec Overview
• Chapter 13: Site-to-Site VPN Operations
• Chapter 14: GRE Tunneling over IPsec
• Chapter 15: IPsec High Availability Options
• Chapter 16: Configuring Cisco Easy VPN
• Chapter 18: Cisco Device Hardening
• Chapter 19: Securing Administrative Access
• Chapter 20: Using AAA to Scale Access Control
• Chapter 21: Cisco IOS Threat Defense Features
• Chapter 22: Implementing Cisco IOS Firewalls
• Chapter 23: Implementing Cisco IDS and IPS

Chapter 3: Using Cable to Connect to a Central Site

Cable System Standards

• National Television Standards Committee (NTSC) - North America
• Phase Alternating Line (PAL) - Europe, Asia, Africa, Australia, Brazil, and Argentina
• Systeme Electronic Couleur avec Memoire (SECAM) - France and Eastern Europe

Cable System Components

• Antenna Site - The site at which a cable provider's main receiving antennas are located
• Headend - A master facility where signals are processed and distributed over the cable network
• Transportation network - Connects remote antenna sites to the headend(s)
• Distribution network - Distributes signals to end users; often contains a Hybrid Fiber-Coaxial (HFC) infrastructure
• Subscriber drop - Connects the subscriber to the distribution network

The Radio Frequency (RF) range is 5 MHz to 1 GHz.

Data-Over-Cable Service Interface Specifications (DOCSIS)

• Downstream frequencies: 50 - 860 MHz
• Upstream frequencies: 5-42 MHz

DOCSIS allows for channel widths of 200 kHz, 400 kHz, 800 kHz, 1.6 MHz, 3.2 MHz, and 6.4 MHz.

DOCSIS 1.0 and 1.1 utilize TDMA; DOCSIS 2.0 can utilize TDMA or synchronous code division multiple access (S-CDMA).

Media access control is done on a request/grant system, minimizing collisions.

• Cable Modem Termination System (CMTS) - Responsible for signal (de)modulation; typically resides in the headend
• Cable Modem (CM) - CPE (de)modulation device

DOCSIS 2.0 provides for up to 40 Mbps downstream and 30 Mbps upstream. DOCSIS 3.0 is capable of up to 160/120 Mbps.

Cable modem boot process

1. Downstream setup
2. Upstream setup
3. Layer 1 and 2 establishment
4. IP address allocation (DHCP)
5. TFTP DOCSIS configuration file
6. Register QoS with CMTS
7. IP network initialization