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High Speed Internet Access for the Home Presented by: David F. Soll Vice President of Advanced Technology
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Agenda High Speed Service Options Connection Methodologies Network Address Translation Firewalls Questions
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High Speed Service Options Cable Modem Bus Topology Always Connected Asymmetric Send and Receive speeds Speeds up to 8 Megabits per second Advertising 1.5 MBPS receive Advertising 128 KBPS send Typical throughput of 500 Kilobits per second to 4 Megabits per second receive Utilizes a form of DHCP Uses machine name instead of MAC address All addresses are reserved You always get the same IP address Cost about $39 per month (in addition to basic cable) About 3.6 Million subscribers in the year 2000
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High Speed Service Options xDSL Digital Subscriber Lines ADSL – Asymmetric DSL SDSL – Symmetric DSL HDSL – High Data Rate DSL Star Topology Speed depends on the distance to a switch Maximum of 32 Megabits per second downstream Current equipment only capable of 6 MBPS Maximum of 1 Megabit per second upstream Typical speeds top out at 640 KBPS Many xDSL vendors use PPPoE This means dial-up rather than dedicated connections The same IP address is not guaranteed Cost typically about $49 per month About 2 million subscribers in the year 2000
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High Speed Service Options Satellite Yes!!! Two-way satellite is available and affordable High speed receive, lower speed send Long latency due to distance Largest Provider is Hughes Electronics which has merged: DirecPC (http:www.direcpc.com) EchoStar (http:www.dishnetwork.com) Typical Speeds From 300 KBPS to 2 MBPS receive From 64 KBPS to 256 KBPS send Typical installation cost of $500 to $1,000 Cost from $29 to $700
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Connection Methodologies Most services provide for a single PC Two ways to add more PC’s to the Internet connection: Pay for more connections Use a router with NAT (discussed later) Typically you pay per IP address NAT tricks the provider into thinking that there is only one machine connected
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Connection Methodologies Single PC
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Connection Methodologies Multiple PC’s with a Router PC
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Connection Methodologies Multiple PC’s with a Router
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Network Address Translation Translates an internal, non-Internet accessible IP address to one that can live on the Internet Local LAN utilizes Private Internet Address (PIA) Typically 192.168.x.x Also available 10.x.x.x and 172.16.x.x PIA’s are guaranteed not to be found anywhere on the Internet
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Network Address Translation Example Browser session going through NAT Browser starts and requests a page The request comes from a PIA and a randomly selected port number The NAT router receives this request and forwards it to the Internet, except with its IP address and a port number that it randomly selects The router keeps a table of translations for IP Address/Port Numbers A Web server responds to the router’s IP address and port The NAT router looks up the translation and forwards the packet to the original PIA address and port After a time-out period, the translation is removed from the table
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Firewalls NAT does a fairly good job of protection, but not perfect A hacker can “tail-gate” in, following a legitimate packet Firewalls are not always necessary, but do provide functionality that may prove to be valuable Many firewalls do protect against Viruses or Trojan Horse programs
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Firewalls What is a firewall? A firewall ABSOLUTELY ISOLATES your computer from the Internet using a “wall of code” that inspects each individual “packet” of data as it arrives at either side of the firewall — inbound to or outbound from your computer — to determine whether it should be allowed to pass or be blocked. Three types of blocking traffic: Stateless Stateless packets can be filtered on a Windows machine without any additional code State full Windows can not filter traffic based on state Firewalls provide state full traffic filtering Must be state full to detect viruses and trojan horses Proxy Application specific
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Firewalls Two major types of firewalls Centralized Provides protection for an entire network Protects multiple machines Personal Provides protection only for one machine Better able to handle virus and Trojan horse protection A combination of both firewall types can be the most secure
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Firewalls Port Monitors Software that monitors IP ports and attempts to protect them against malicious packets Many of them don’t work too well and can even invite hacking since they acknowledge existence of a listener on a port If you want to monitor port access attempts, find a high quality one that will monitor but won’t respond to ports that don’t have a listener STAY AWAY FROM PORT MONITORS!
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Firewalls You need a Personal Internet Firewall if: Your computer's files need to be accessed remotely across the Internet. You are operating any sort of Internet server such as Personal Web Server. You use any sort of Internet-based remote control or remote access program such as PC Anywhere, Laplink, or Wingate. You want to properly and safely monitor your Internet connection for intrusion attempts. You want to preemptively protect yourself from compromise by "inside the wall" Trojan horse programs like NetBus and Back Orifice.
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Firewalls BlackICE Defender - $40.00 Symantec/Norton Personal Firewall - $50.00 Zone Alarm - Free Zone Alarm Pro - $40.00 Tiny Personal Firewall – Free Sygate Personal Firewall – Free McAfee Firewall - $30.00 PC-Viper - $20.00 AtGuard – Discontinued Conseal Desktop eSafe Desktop PrivateFirewall Lockdown 2000 Sphinx - $50.00 CyberArmor Deerfield Personal Firewall – $30.00
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Firewalls Leak-Proof Firewalls (Based on GRC’s Leak Test) McAfee Firewall - v 2.15+ Sygate Personal FW - v 4.0+ (FREE for personal use) Symantec/Norton - v 2.55+ Tiny Personal FW - v 2.0.7+ (FREE for personal use) ZoneAlarm – Never Leaked (FREE) ZoneAlarm Pro – Never Leaked Leak-Proof but Strange Firewalls (Based on GRC) PC-Viper – Doesn’t leak but seems unfinished
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Firewalls Leaky (unsafe) Personal Firewalls (Based on GRC) Masquerade Vulnerable AtGuard Conseal Desktop eSafe Desktop Private Firewall 2.0 Doesn’t Block Unknown Trojans or Viruses BlackICE Defender No Provision to block Trojans, Viruses, or Spyware Conseal PC Freeware Lockdown 2000
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Firewalls Sources for more information: Gibson Research Corporation – Best source of firewall information grc.com – Great Web Site Includes free and commercial software Has a Firewall testing program Checkout Shields Up!
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Questions ?
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High Speed Internet Access for the Home Presented by: David F. Soll Vice President of Advanced Technology
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