Chapter 15 Networks Part 2 ARPANet in 1969 1 Hofstra University - - PowerPoint PPT Presentation

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Chapter 15 Networks Part 2 ARPANet in 1969 1 Hofstra University - - PowerPoint PPT Presentation

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Chapter 15 Networks Part 2 ARPANet in 1969 1 Hofstra University - CSC005 11/29/06 Internet Standards and RFCs Internet Architecture Board (IAB) - overall architecture Internet Engineering Task Force (IETF) - engineering and development

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Chapter 15

Networks – Part 2

ARPANet in 1969

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Internet Standards and RFCs

Internet Architecture Board (IAB)

  • overall architecture

Internet Engineering Task Force (IETF)

  • engineering and development

Internet Engineering Steering Group (IESG)

  • manages the IETF and standards process
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Request For Comments (RFC)

RFCs are the working notes of the Internet research and development community

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Standardization Process

Stable and well understood Technically competent Substantial operational experience Significant public support Useful in some or all parts of Internet

Key difference from ISO: operational experience

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RFC Publication Process

Internet draft Experimental Informational Proposed standard Draft standard Internet standard Historic IETF IESG < 6 months > 6 months > 4 months two independent implementations

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How To Find RFCs

http://www.rfc-editor.org/rfcsearch.html

  • Search for RFCs

Some Popular Ones:

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Modern Life In Cyberspace...

http://www.aclu.org/pizza/images/screen.

...All I Wanted Was A Pizza!

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Introduction to

Network Security

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Security Attacks

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Security Services

Confidentiality – protection from passive attacks Authentication – you are who you say you are Integrity – received as sent, no modifications, insertions, shuffling or replays

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Security Services

Nonrepudiation – can’t deny a message was sent or received Access Control – ability to limit and control access to host systems and apps Availability – attacks affecting loss or reduction on availability

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Network Security Model

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Network Security Model

Design algorithm Generate secret information to be used Develop methods to distribute and share info Specify a protocol to be used by the two principals Four basic tasks in designing a security service:

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Protocols – Simple To Complex

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Protocols in a Simplified Architecture

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Protocol Data Units in TCP/IP

TCP Header User Data IP Header User Data Network Header User Data User Data Application Byte Stream TCP Segment IP Datagram Network-level Packet

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Operation of a Protocol Architecture

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TCP and UDP Headers

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IP Headers

128-bit field 32-bit field QoS max # allowable hops

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TP/IP Concepts

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Some TCP/IP Protocols

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Assigned Port Numbers

Sun NFS 2049 kerberos 88 radiusauth 1812 http 80 rip2 520 DNS 53 isakmp 500 rip 39 https 443 smtp 25 ldap 389 telnet 23 ntp 123 ftp 21 nntp 119 ftp-data 20 pop3 110 echo 7 Service Port Service Port

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Configuration of TCP/IP

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Alternate Routing Diagram

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Ethereal

Ethereal is a free network protocol analyzer for Unix and Windows Packet Sniffer - data can be captured "off the wire" from a live network connection www.ethereal.com - Everything you ever wanted to know about ethereal wiki.ethereal.com - This is the “User's Manual;” also has has a nice “References” section

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cookie is captured getting a quote business.nytimes.com dns query ACK

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Ethereal Etiquette

Be careful when and where you use this tool It makes people nervous Use prudence with the information you collect When in doubt, seek permission!

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Network Access Security Model

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Information Security

Physical Administrative “Lockup the file cabinet”

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Private Networks

Isolated to individual organizations Emergence of computer security Sharing a system Protecting data

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Networking

Networks start talking to each other Gateways Arpanet TCP/IP Everywhere Vinton Cerf, “IP On Everything!”

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Maturing of the Internet

Telephones used by 50% of worlds population Internet attains similar level of growth by 2010 – max growth Connecting computers and programmable devices More devices than people

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Early Hacking

Cap’n Crunch cereal prize Giveaway whistle produces 2600 MHz tone Blow into receiver – free phone calls “Phreaking” encouraged by Abbie Hoffman Doesn’t hurt anybody

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Captain Crunch

John Draper `71: Bluebox built by many Jobs and Wozniak were early implementers Developed “EasyWriter” for first IBM PC High-tech hobo White-hat hacker

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The Eighties

1983 – “War Games” movie Federal Computer Fraud and Abuse Act - 1986 Robert Morris – Internet worm -1988 Brings over 6000 computers to a halt $10,000 fine His Dad worked for the NSA!!!

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It Got Worse

1995 – Kevin Mitnick arrested for the 2nd time Stole 20,000 credit card numbers First hacker on FBI’s Most Wanted poster Tools: password sniffers, spoofing http://www.2600.com

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Tracking Attacks

http://www.cert.org

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Just because you’re paranoid, doesn’t mean they’re not out to get you!

  • Anonymous
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Firewalls

Figure 15.8 A firewall protecting a LAN

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Firewalls Make It To The Movies

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Why Firewalls?

Internet connectivity is no longer an

  • ption for most corporations

The Internet allows you access to worldwide resources, but… …the Internet also allows the world to try and access your resources This is a grave risk to most

  • rganizations
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Why Firewalls?

A firewall is inserted between the premises network and the Internet Establishes a perimeter Provides a choke point where security and audits can be imposed Single computer system or a set of systems can perform the firewall function

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Good Fences Make Good Neighbors – Robert Frost, “Mending Wall”

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Design Goals

All traffic, from inside to outside and vice versa, must pass through the firewall Only authorized traffic (defined by the security policy) is allowed to flow Firewall is immune to penetration – uses a trusted system

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Other Types Of Firewalls

Personal Firewalls Appliances – personal firewall appliances are designed to protect small networks such as networks that might be found in home

  • ffices

Provide: print server, shared broadband use, firewall, DHCP server and NAT

(NB: This is not an endorsement of any product)

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Viruses

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Viruses

A virus is a submicroscopic parasitic particle that infects cells in biological

  • rganisms.

Viruses are non-living particles that can only replicate when an

  • rganism reproduces the

viral RNA or DNA. Viruses are considered non-living by the majority

  • f virologists

www.virology.net

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Viruses

Viruses: code embedded within a program that causes a copy of itself to be inserted in other programs and performs some unwanted function Infects other programs Code is the DNA of the virus

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Worms

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Worms

Worms: program that can replicate itself and send copies to computers across the network and performs some unwanted function Uses network connections to spread from system to system

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Useful Websites

http://www.rfc-editor.org/rfcsearch.html Search RFCs http://www.cert.org Center for Internet security http://www.counterpane.com/alerts.html Some recent alerts

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Assignment #3

Research these two RFCs: RFC1129 and

  • RFC968. Given a brief - paragraph, not a

single sentence – description based on the abstract, introduction, or basic content Pick google.com and one other site. Using whois and ARIN, get as much information as possible about the IP addressing, the DNS and the site (location, owner, etc.) Due next Wednesday, December 6 – or you can email it earlier

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Homework

Read Chapter Fifthteen – and review slides ...Next Class We'll Cover Artificial Intelligence...

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...Have A Nice Weekend

“The City” At 1200 Feet In December