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PROVIDING TELEWORKER SERVICES Accessing the WAN – Chapter 6

Sandra Coleman, CCNA, CCAI

OBJECTIVES• Describe the enterprise requirements for providing

teleworker services

• Explain how broadband services extend Enterprise Networks including DSL, cable, and wireless

• Describe how VPN technology provides secure teleworker services in an Enterprise setting

ENTERPRISE REQUIREMENTS FOR PROVIDING

TELEWORKER(TELECOMMUTER) SERVICES

• Describe the benefits of teleworkers for business, society and the environment.

ENTERPRISE REQUIREMENTS FOR PROVIDING TELEWORKER SERVICES

• Traditional private WAN – Frame Relay, ATM, leased lines. Provide remote access solutions.

• IPsec VPNs – offer flexible and scalable connectivity

• Site-to-site connections – Most common – broadband, Secure VPN over public internet

ENTERPRISE REQUIREMENTS FOR PROVIDING TELEWORKER SERVICES

• At home: Computer, broadband access (DSL, etc), VPN router

• At the office: VPN-capable routers, security appliances, authentication and mgt devices.

HOW BROADBAND SERVICES EXTEND ENTERPRISE NETWORKS

• Dialup – inexpensive,56K speeds

• DSL – more expensive, faster connection< >=200K

• Cable modem – similar to DSL, shared service, so speed is affected by # users

• Satellite – Satellite modem, radio signals, <128K < 512K

HOW BROADBAND SERVICES EXTEND ENTERPRISE NETWORKS

• Headend – where signals are first received, processed and distributed downstream.

• Distribution network – Tree & branch system of cabling.

• Subscriber drop – connection of subscriber to the service.

HOW BROADBAND SERVICES EXTEND ENTERPRISE NETWORKS

• DSL-high speed connection over copper wires. Not all bandwidth of phone wires was being used, so ADSL took up the slack.

• Local loop (last mile) – NOT as shared medium, therefore each user has a direct connection to the DSLAM (DSL Access Multiplexer).

HOW BROADBAND SERVICES EXTEND ENTERPRISE NETWORKS

• Provides mobility –

• Municipal – gov’t working with ISP to deploy Wi-Fi

• WiMAX – (Worldwide Interoperability for Microwave Access) higher speeds, greater distances. Aimed at providing coverage to rural areas out of reach by DSL

• Satellite – available worldwide. Approx 500kbps.

Types of wireless

SECURITY FOR BROADBAND SERVICES EXTEND ENTERPRISE NETWORKS

• 802.11b – 11 Mbps

• 802.11g – 54 Mbps

• 802.11n - > 54 Mbps

• 802.16 – WiMAX 70 Mbps, with a range of 30 miles.

VPN TECHNOLOGY

What is a VPN? virtual WAN infrastructure that connects business partner sites to a corporate network.

Virtual – Private network over a public network

Private – data is encrypted

Each LAN is an IsLANd – Each inhabitant of the island gets their own submarine to connect to the mainland which is fast, at your disposal, can be invisible, and is very dependable.

• Cost savings – No more dedicated lines!

• Security – Advanced encryption and authentication protocols

• Scalability – Easy to add new users without adding significant infrastructure changes.

VPN TECHNOLOGY

TYPES OF VPN’S

• Site-to-Site – access between 2 physical sites.

• Remote-access – gives remote users acces to the corporate network over a shared infrastructure. Used by teleworkers and mobile users.

VPN COMPONENTS

• An existing network (clients/servers)

• Connection to the internet

• VPN gateways, such as routers, firewalls, etc, that act as endpoints to establish, maintain, and manage VPN connections

• Appropriate software to create and manage VPN tunnels

CHARACTERISTICS OF SECURE VPNS

• Data confidentiality – protect data from eavesdroppers! VPNs do this using mechanisms of encapsulation and encryption

• Data Integrity – guarantees that no tampering or alterations to the data occur while it travels from source to destination. Typicallly done using a hash feature.

• Authentication – ensures that a message comes from an authenticated source and goes to an authenticated destination. Uses passwords, digital certificates, smart cards, and even biometrics!

VPN TUNNELING

• Tunneling allows the use of public networks to carry data for users as though the users had access to a private network. See the figure on pg. 410 for an example

VPN ENCRYPTION

• Encryption – the act of coding a given message into a different format to alter the data’s appearance, making it incomprehensible tot hose who are not authorized to view it.

• Uses an algorithm (DES, 3DES, AES, RSA)

• Three basic components – • Key• Cipher• Message

• Hashes – MD5, SHA-1

IPSEC SECURITY PROTOCOLS

• IPsec - a protocol suite for securing IP communications that provides encryption, integrity, and authentication.

• 2 main framework protocols

• Authentication Header (AH) – used when confidentiality is not required. No encryption. Usually used with ESP

• Encapsulation Security Payload (ESP) – provides confidentiality and authentication

WHAT TO DO NOW?

• Online Test – On until Wednesday, April 3, midnight!

• Test grade for Ch. 6 will be the Packet Tracer Skills Integration Challenge on pg. 219. (LSG04-PTSkills6.pka)

• You will do this NOW!