Ride the LightA guide to the internet, telephony and computer technology in the 21st century.

Presentation for MIS-110November 1, 2005Presenter: Michelle Davies

Agenda

Introduction Core Computing Values Telephony Internet Technology IP Addressing Internet Security/Abuse Conclusion

Working Model OSI(Troubleshooting from the Ground Up)

Base

The word “base” in math is used to refer to a particular mathematical object that is used as a building block. The most common uses are the related concepts of the number system….

Base Number System

2 Binary

3 Ternary

4 Quaternary

5 Quinary

6 Senary

7 Septenary

8 Octal

9 Nonary

10 Decimal

11 Undenary

12 Duodecimal

16 Hexadecimal

20 Vigesimal

60 Sexagesimal0-9

0-9 followed by A-F

0s & 1s

Call Routing

Phone Systems

Nortel Centrex-maintained by telco, more reliable, more expensive, no CPE purchase

Norstar KSU (Key Systems Unit)-customer maintained, cheaper than centrex, has limitations, CPE purchase is expensive

PBX (Private Branch Exchange)-also known as a small dms100 switch, performs complex call routing – Best Area Call Selection, Cheapest Rate Selection

Telco Terminology

POTS – Plain Old Telephone Service FX – Foreign Exchange (Hard & Soft) DSL – Digital Subscriber Line Telco – Telephone Company CPE – Customer Premise Equipment PBX – Private Branch Exchange KSU – Key Systems Unit OOS – Out of Standard / Out of Service NID – Network Interface Device, point of demarc.

Dial-up

Dial-up Info

4 Standards – k56flex, x2, v.90, v.92 Getting connected at 56Kbps is not impossible but usually unlikely. When

56k technology first came out, the signal strength required for a 56000 bps connection exceeded FCC regulations, so 53,333 bps was the absolute maximum. 54,666 bps and 56,000 bps connections are possible, but usually very unstable due to fluctuations in the local loop quality. Typically V.90 connections are in the 40s and are very sensitive to noise in shoddy phone lines or passing through several connections, like running the phone through a fax machine, an answering machine, a splitter, or even a surge protector. The best setup is to use a quality V.90 modem with updated firmware and/or drivers connected directly to the wall jack with one short phone cord no more than 10 feet in length. Then add devices (like the surge protector) until you find the culprit. If this set up still does not allow a V.90 connection, it likely has to do with the quality of the phone lines/local loop and needs to be taken up with the telephone company.

Source: modemhelp.net

DSL

DSL Info

Several types of DSL exist, ADSL, SDSL, XDSL (to name a few)

DSL vs. Cable, why DSL is better. -Advantages & Disadvantage

Loop Lengths Splitter is placed on phone line to divide

between voice frequency (lower frequencies) and data (higher frequencies)

T1 Technology

T1 Information

24 Channels each at 64k. Max speed = 1.544 Mbps

Sometimes sold as burstable or as fractional Customer’s network is connected to t1 via a

router and CSU/DSU, then there is a PTP circuit between customer and ISP, the circuit is terminated at the Telco CO via a CSU/DSU and a router

ARINThere are several routing registries around the world…

ARIN (American Registry for Internet Numbers) – Covers the U.S. and Canada AfriNIC - Responsible for providing vital resource allocation and registration services for the continent of Africa on

behalf of the Internet community. LACNIC - Latin American and Caribbean IP Address Regional Registry. It is responsible for providing vital resource

allocation and registration services to the Latin American and Caribbean region. RIPE NCC - performs activities primarily for the benefit of the membership in Europe, the Middle East, and parts of

Asia; mainly activities that its members need to organize as a group, even though they may compete in other areas. APNIC - serves the entire Asia Pacific region, comprising sixty-two economies in Asia and Oceania. Each “NIC” performs critical functions… Registration Services pertain to the technical coordination and management of Internet number resources. They

include: IP address space allocation, transfer, and record maintenance ASN allocation, transfer, and record maintenance Directories

Registration transaction information (WHOIS) DNS (Reverse) Every allocation provided to isp’s and end users greater than a /29 must be justified to ARIN by submitting the required

information to ARIN. Without tight controls on address space, we would soon run out as the address pool is finite.

RFCs

Located at http://www.rfc-editor.org RFCs are the protocol standards for the

internet, networking, routing, etc RFCs related to IP Addressing: 1918, 791 IPv6 vs. IPv4

Subnetting – Class C

CIDRTotal # of

AddressesTotal # of Useable

Addresses Subnet Mask

/24 256 254 255.255.255.0

/25 128 126 255.255.255.128

/26 64 62 255.255.255.192

/27 32 30 255.255.255.224

/28 16 14 255.255.255.240

/29 8 6 255.255.255.248

/30 4 2 255.255.255.252

Subnetting – Class B

bits Subnet Mask CIDR # Subnets # Hosts Nets * Hosts

2 255.255.192.0 /18 2 16382 32764

3 255.255.224.0 /19 6 8190 49140

4 255.255.240.0 /20 14 4094 57316

5 255.255.248.0 /21 30 2046 61380

6 255.255.252.0 /22 62 1022 63364

7 255.255.254.0 /23 126 510 64260

8 255.255.255.0 /24 254 254 64516

Subnetting – Class A

bits Subnet Mask CIDR # Subnets # Hosts Nets * Hosts

2 255.192.0.0 /10 2 4194302 8388604

3 255.224.0.0 /11 6 2097150 12582900

4 255.240.0.0 /12 14 1048574 14680036

5 255.248.0.0 /13 30 524286 15728580

6 255.252.0.0 /14 62 262142 16252804

7 255.254.0.0 /15 126 131070 16514820

8 255.255.0.0 /16 254 65534 16645636

Today’s Latest Internet Threats

Threats Spam Viruses Trojans Phishing Spyware DDOS Attacks Pop Ups

Solutions Spam Filtering at ISP

level or 3rd Party Software Anti Spyware Programs Pop Up Stoppers Anti Virus Programs Basic Computer Literacy

Security Threats (detail) Spam -- In general, spyware is any technology, such as tracking software, that aids in gathering information about a person or

organization without their knowledge.

Viruses -- A program or piece of code that is loaded onto your computer without your knowledge and runs against your wishes.

Trojans -- A destructive program that masquerades as a benign application. Unlike viruses, Trojan horses do not replicate themselves but they can be just as destructive.

Phishing – (fish´ing) (n.) The act of sending an e-mail to a user falsely claiming to be an established legitimate enterprise in an attempt to scam the user into surrendering private information that will be used for identity theft.

Spyware -- Any software that covertly gathers user information through the user's Internet connection without his or her knowledge, usually for advertising purposes.

DDOS Attacks -- Short for Distributed Denial of Service, it is an attack where multiple compromised systems (which are usually infected with a Trojan) are used to target a single system causing a Denial of Service (DoS) attack.

Pop Ups -- A type of window that appears on top of (over) the browser window of a Web site that a user has visited. In contrast to a pop-under ad, which appears behind (in back of) the browser window, a pop-up is more obtrusive as it covers other windows, particularly the window that the user is trying to read. Pop-ups ads are used extensively in advertising on the Web, though advertising is not the only application for pop-up windows.

Websites of InterestTech Websites

Name Address

DSL Reports http://www.dslreports.com

Church of the Swimming Elephant http://www.cotse.com

Modem Help http://www.modemhelp.org

Modem Help http://www.modemhelp.net

Slashdot http://www.slashdot.org

Tech TV http://www.g4tv.com

IP Subnet Calculatorhttp://

www.sonicusers.com/tools/ipcalculator/ipcalc.aspSymantec Security

Response http://www.sarc.com/

Websites of Interest (cont).

US CERT (Computer Emergency Awareness Team) http://www.us-cert.gov/

Wayback Machine http://www.waybackmachine.org

RFC Editor http://www.rfc-editor.org

Internet Traffic Reporthttp://www.internettrafficreport.com/main.htm

Traceroute.org http://www.traceroute.org

Open RBL http://openrbl.org

Mail Relay Testing http://www.abuse.net/relay.html

MAPS http://www.mail-abuse.com/

More Websites of InterestARIN http://arin.net/

CNET http://www.cnet.com

Google News http://news.google.com

Bullguard http://www.bullguard.com/news/

Apple http://www.apple.com

Microsoft http://www.microsoft.com

Microsoft Support http://support.microsoft.com

Webopedia http://www.webopedia.com

Home Network Help http://www.homenethelp.com

Practically Networked http://www.practicallynetworked.com

How Stuff Works http://www.howstuffworks.com

AVG Anti Virus http://www.grisoft.com/

Ad Aware http://www.lavasoftusa.com/software/adaware/

Spybot Search & Destroy http://www.safer-networking.org/en/download/

Google Pop-up Stopper http://toolbar.google.com

Urban Legends http://www.scambusters.org/legends.html