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Remote Access and Long-Distance Communications. Typical Telephone System. Typical telephone system consists mainly of local carriers and long-distance carriers Local carrier is often referred to as a Local Exchange Carrier (LEC)
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Remote Access and Long-Distance Communications
Typical Telephone System Typical telephone system consists mainly of local carriers and long-distance carriers Local carrier is often referred to as a Local Exchange Carrier (LEC) Local Central Office connects to long-distance carriers and to other Local Central offices via a trunk line
Customer Premises • Connects to the Local Central Office through wiring referred to as the local loop • The section of wiring between customer premises and the Local Central Office. • Customer premises and local loop are demarcated by the Point of Presence (PoP) • The point where the telephone company line connects to the subscriber line.
Integrated Services Digital Network (ISDN) • Provides a fully digital connection • Requires an ISDN modem • Three categories • Basic Rate ISDN (BRI-ISDN) • Primary Rate ISDN (PRI-ISDN) • Broadband ISDN (B-ISDN)
Cable Internet Service Uses the Cable television distribution system to provide Internet access Typically requires a Cable modem Asymmetrical form of communication
Cable Internet Service Bandwidth Bandwidth fluctuates according to number of subscribers connected to the head-end using the system at the same time Speed also affected by type of data downloaded and overall distance from Cable service provider
Digital Subscriber Line (DSL) • High-speed internet access technology that uses the local loop • Distance between DSL modem and Local Central Office is 1,000 to 18,000 feet • Maximum distance depends on variation of DSL used and any special equipment on the telephone line, such as a loading coil • A device used to amplify voice signals.
Applied Networking A customer is deciding on whether to use DSL, Cable, or Satellite for Internet service. What might you tell the customer in regards to advantages and disadvantages of each that would help in their decision?
Synchronous Optical Network (SONET) Standard choice for connecting global-sized networks spanning the nation and oceans Uses fiber-optic cable and special termination equipment Uses a multiplexer to carry data, voice, and video on the same channel Designed as a dual-ring topology
Remote Access Configurations • Three common ways to set up remote dial-in access on a server are: • Allow dial-in to the remote access server only • Allow dial-out from the remote access server only • Allow full-service dial-in and dial-out on the remote access server
Remote Desktop Protocol (RDP) Allows user to access and use a remote computer Encrypts the contents of packets sent across the network
Serial Line Internet Protocol (SLIP)andPoint-to-Point Protocol (PPP) Enable PC to connect to remote network using serial line connection SLIP is asynchronous protocol that supports only TCP/IP PPP is asynchronous and synchronous protocol that supports TCP/IP, IPX, and AppleTalk protocols
Point-to-Point Tunneling Protocol (PPTP) Enhanced version of PPP Encapsulate the existing network protocol (IP, IPX, AppleTalk, etc.) Encrypts data Supports remote access service and network access authentication
Point-to-Point over Ethernet (PPPoE) Enables one or more Ethernet hosts on a network to establish individual PPP connections with an ISP
Multilink Point-to-Point Protocol (MLPPP) Access server and client must have MLPPP enabled Can use Bandwidth Allocation Protocol (BAP) to allow the number of lines used to change on demand Controlling number of lines used based on demand is cost effective
Layer 2 Forwarding (L2F) Makes use of a VPN when using the public Internet Can work directly with ATM and Frame Relay Supports more than one connection Requires special equipment on the host side to support data transfers and a Microsoft server class of operating system
Layer 2 Tunneling Protocol (L2TP) Combines the L2F and PPTP protocols Industry standard tunneling protocol that uses IPSec to encrypt the contents of the encapsulated PPP protocol
Multi-Protocol Label Switching (MPLS) • Provides a faster means of distributing packets from edge router to edge router • Eliminates the need for a router to determine best route • Two main applications for MPLS are: • Traffic shaping • VPN
Virtual Private Network (VPN) Creates a private connection over the Internet or Intranet VPN software and firewalls provide security Four most common protocols used in a VPN are PPTP, L2F, L2TP, and IPSec
In class lab Roberts Labs 69,70,71 Next Class Labsim Homework 10.2.1-10.2.3