Ride the LightA guide to the internet, telephony and computertechnology 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 0s & 1s Base Number System 2 Binary The word “base” in math is 3 Ternary used to refer to a particular 4 Quaternary mathematical object that is 5 Quinary used as a building block. The 6 Senary most common uses are the 7 Septenary related concepts of the number 8 Octal system…. 9 Nonary0-9 followed by A-F 10 Decimal 11 Undenary 12 Duodecimal 16 Hexadecimal 20 Vigesimal 0-9 60 Sexagesimal
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 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 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 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
ARIN There 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 Total # of Total # of UseableCIDR Addresses 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
Today’s Latest Internet Threats Threats Solutions Spam Spam Filtering at ISP Viruses level or 3rd Party Software Trojans Anti Spyware Programs Phishing Pop Up Stoppers Spyware Anti Virus Programs DDOS Attacks Basic Computer Literacy Pop Ups
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 users 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 Interest Tech Websites Name AddressDSL Reports http://www.dslreports.comChurch of the Swimming Elephant http://www.cotse.comModem Help http://www.modemhelp.orgModem Help http://www.modemhelp.netSlashdot http://www.slashdot.orgTech TV http://www.g4tv.com http://IP Subnet Calculator www.sonicusers.com/tools/ipcalculSymantec Security Response http://www.sarc.com/