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NYC College of Technology CST3607: Interconnectivity (Fall 2017) Contents: Announcements Assignment Requirements Required Texts
Class Notes & Assignments : September, October, November, December Recommended Web Sites and Books
Log into Blackboard Cisco IOS and Router Command Reference Bit Patterns of Often Used Subnet Mask Values (pdf) OSI Reference Model (pdf) IP Address Conversions : Decimal to Base-256 / Base-256 to Decimal
Announcements Final Exam: Tuesday: Dec. 19, 2017 Assignment #6: Due Thurs. 12/14/2017
Assignment #5: Due Tues. 12/12/2017
Exam #3: Thursday Nov. 30, 2017
Quiz #2: Due Sun. 10/29/2017 before 12pm (noon)
Exam #2: Thursday, Oct. 26, 2017
Quiz #2: Due Sun. 10/8/2017 before 5pm
Exam #1: Thurs. 10/5/2017
Quiz #1: Subnetting: Tues. 10/3/2017
Assignment #3: Due Tues. 10/3/2017
Assignment #2: Due Thurs. 9/28/2017
Assignment #1: Due Tues. 9/26/2017
Important note about sending E-Mail to Me Only use the e-mail address I gave you in class to communicate with me. Do not use my cuny.edu address and do not e-mail me via Blackboard. [ Top ] [ Home ]
Required for all Assignments Make sure that your full name is neatly written on your assignment. Submit a typed hardcopy at the beginning of class. If you use the RTF or DocX template I supply, type your answers in the table below each question. If you do not use the template I supply, make sure your answers stand out from the text of the question. i.e. bold or underlined, not both. Do not double space. Do not type your answers in all uppercase. Print out your assignments before you come to class. Do not rely on the printer or network in our classroom to be available or functional. Make sure that the correct assignment number and chapter are on your paper. Be mindful that the assignment number is not always the same as the chapter number. E-mail your assignment only if you are going to be absent, and at least 2 hours before class starts, on the day that the assignment is due. This should ensure that I receive your assignment before the start of class.
No late assignments will be accepted.
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Required Text CCNA Routing and Switching Complete Study Guide: Exam 100-105, Exam 200-105, Exam 200-125, 2nd Edition Author(s): Todd Lammle (Lammle.com) ISBN: 978-1-119-28828-2 Publish date: September 2016 Publisher: Sybex Also on Amazon.com eBook: VitalSource.com Use the LammleSim IOS "IOS CCNA R/S SIM" to practice the hands-on labs.
Reference Texts Connecting to the Internet: A Practical Guide About LAN-Internet Connectivity Author(s): Andrew F. Ward Publisher: Addison-Wesley, 1999. ISBN: 0-201-37956-2 Used copies are available through Amazon.com [ Top ] [ Home ]
Class Notes & Assignments Tuesday: Aug. 29, 2017
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News & Tools The Final Exam will be on Tuesday: December 19, 2017 The Privacy Paradox Challenge: A week of challenges with thousands of other "Note to Self" podcast listeners Feb 6-10. Government Secrets Worth Leaking... or Keeping? Note to Self (Valut-7 & Stingray) Surveillance Self-Defense is Electronic Frontier Foundation (EFF)'s00 guide to defending yourself and your friends from surveillance by using secure technology and developing careful practices. security.txt: "When security risks in web services are discovered by independent security researchers who understand the severity of the risk, they often lack the channels to properly disclose them. As a result, security issues may be left unreported. Security.txt defines a standard to help organizations define the process for security researchers to securely disclose security vulnerabilities." Microsoft Windows and Office ISO Download Tool: This tool allows an easy way to download genuine Windows 7, Windows 8.1 and Windows 10 disk images (ISO) directly from Microsoft's servers, as well as Office 2007, Office 2010, Office 2013, Office 2016, and Office for Mac.
In Class The Class Web page is located at ConsciousVibes.com (No www. prefix!) All assignments, reading and written, will be posted only on the class Web page Assignments will not be posted on Blackboard. Make sure that you can log into Blackboard and access our class section as soon as possible. Exams and quizzes will be administered via Blackboard Free classes are available from the Office of Adult & Continuing Education
Principle of Least Privilege Why You Should Not Run as an Administrator or Root User How to Change Your Account to a Standard User 1. Create a new local account that’s an administrator, with a strong password. 2. Log in under the new local administrator account to verify that it’s working properly 3. Change the account type of your original account to a Standard user 4. Log in under your original account, that's now a Standad user. The times that you need elevated rights, UAC will prompt you for your administrator account.
How and Why AutoPlay / AutoRun in Windows Should be Disabled The simple way to mitigate over 90% of Critical Microsoft Vulnerabilities Avecto's Analysis of Patch Tuesday vulnerabilities show that, of the 147 vulnerabilities reported by Microsoft in 2013 with a Critical severity rating: 92% were concluded to be mitigated by removing administrator rights 96% of Critical vulnerabilities affecting Windows Operating Systems could be mitigated by removing admin rights 100% of all vulnerabilities affecting Internet Explorer could be mitigated by removing admin rights 91% of vulnerabilities affecting Microsoft Office could be mitigated by removing admin rights. 100% of Critical Remote Code Execution vulnerabilities and 80% of Critical Information Disclosure vulnerabilities could be mitigated by removing admin rights. Malware (short for malicious software. e.g. Virus, Trojan Horse, Worm, Adware, etc.) The key to solving the malware problem is avoidance, not detection and removal.
Rootkit : You can never be sure you've removed all traces of a rootkit. The only way to be certain that your system is clean of malware is to: 1. Backup only your data. (Do not backup any .exe's, .com's as they may have been compromised.) 2. Erase/format the hard drive 3. Do a clean install of the operating system from known safe media. (Do not use the recovery partition, as it may have been compromised too.)
Live AntiVirus and Recovery Discs KNOPPIX Live Disc Download via the "Get Knoppix" menu
Stay Informed! News Sources Krebs on Security Ars Technica Smashing Security Netcast/Podcast with Graham Cluley and Carole Theriault Bleeping Computer: Security News InfoSec Industry The Hacker News SecurityNow! Netcast/Podcast by Steve Gibson and Leo Laporte (Twit.tv) Windows Weekly Netcast/Podcast Hosted by: Leo Laporte, Mary Jo Foley, Paul Thurrott (Twit.tv) Tech News Today Netcast/Podcast (Twit.tv) privacytools.io Router Security The State of Security by Tripwire.com Get Trending Threat Insights Delivered to Your Inbox With Our Free Cyber Daily (RecordedFuture.com)
Studying & Learning Tips Cisco Exam Preparation - Studying for Results How to Study Effectively: 8 Advanced Tips - College Info Geek Strategies For Remembering Everything You Learn Science-Backed Study Tips to Ace a Test How to Ace Calculus: The Art of Doing Well in Technical Courses Deep Work: How to Focus and Resist Distractions (Ep. 100) | College Info Geek Cram.com Flashcards (Search: CCNA) BetterExplained: Learn Right, Not Rote Quizlet.com Flash Cards: CCNA How to Learn Anything... Fast - Josh Kaufman Cisco Learning Network Skills You Need - Helping You Develop Life Skills
Memorize these Bit Patterns of Often Used Subnet Mask Values (pdf) Bit(s) Binary
Decimal
1
10000000 =
128
2
11000000 =
192
3
11100000 =
224
4
11110000 =
240
5
11111000 =
248
6
11111100 =
252
7
11111110 =
254
8
11111111 =
255
Password Managers LastPass is a password manager. It helps you be more secure by making it easy to use a different password for every Web site. LastPass uses: AES-256 bit encryption with PBKDF2 SHA-256 and salted hashes to ensure complete security in the cloud. User data is encrypted and decrypted locally at the device level. Data stored in the vault is kept secret, even from LastPass. The user’s master password, and the keys used to locally encrypt and decrypt user data, are never sent to LastPass’ servers, and are never accessible by LastPass. LastPast Configuration On the Login screen: Uncheck "Remember Email" On the Login screen: Uncheck "Show My LastPass Vault After Login" Under: Preferences > General: enable "Automatically Logoff when all browsers are closed for (mins)" and set the time to 1 min Make sure to: 1. Export your encrypted data: Tools > Export To > LastPass Encrypted File 2. Download and keep a copy of the LastPast executable. This will allow you access your exported data, if LastPass.com is not available or you don't have Internet access. SecurityNow! Episode #256: In-depth review and evaluation of LastPass (00:52:28 - 01:53:00). [Show Notes] Review: LastPass password manager (thetechherald.com) LastPass Review & Rating (PCMag.com) Video: Why use LastPass? Wikipedia Article on LastPass Password Haystacks by Steve Gibson Am I An Idiot for Still Using a Password Manager? Five Best Password Managers Busting Password Myths, Paul Ducklin and Chester Wisniewski take a look at the thorny issue of password rules and regulations. How to choose a strong password - simple tips for better security Random Word Generator Using passphrases of 3 or more random words have proven to be more secure than random characters, as long as they're long enough.
Backing Up: 3-2-1 Rule 3: Have three copies of your files. The original, plus 2 copies 2: On different storage mediums. e.g. separate hard drives, optical (CD/DVD), tape 1: Have a current backup that is offsite and/or online : Mega (encrypted), Carbonite.com, Gmail Sync, Microsoft OneDrive. Note: Any files that may have sensitive information, should be encrypted locally, before they're uploaded/synchronized to the cloud.
Optical Media for Long Term Archives Regular writable optical media, CDs & DVDs, etc., are not reliable for long term storage. The die used with optical media degrade with exposure to light, temperature extremes, etc. Because of this, the data on the media will start to degrade within 1 to 5 years. M-DISC (Millennial Disc) is a write once optical disc technology available in DVD and Blu-ray forms. Millenniata claims that properly stored M-DISC DVD recordings will last 1,000 years, and are readable in conventional optical drives Drives with M-DISC support and M-DISC Media LG Electronics 8X USB 2.0 GP65NG60 Millenniata 4.7GB M-Disc, 10 Pack
Live AntiVirus and Recovery Discs Troubleshoot/Test hardware or recover data KNOPPIX Live Disc, Kali Linux
Troubleshooting Client Network Connectivity Reasons why a client workstation did not get an IP address from the DHCP server within the correct IP address scope of your network, while other client workstations do. Keep it simple. Check the obvious things first. Are both ends of the network cable plugged in? Do you have a link status light? IPConfig /all ping 127.0.0.1 (the loop back, to verify that the IP protocol stack is okay.) Can the problem be reproduced? (Re-boot the computer) Are other workstations getting an IP address in the correct range? Can you ping the DHCP server, from a working system? Have you checked that the IP addresses in the DHCP scope have not been used up? Automatic Private IP Addressing (APIPA) IPv4 Link-Local address assignment (IPV4LL) The Internet Assigned Numbers Authority (IANA) has reserved 169.254.0.0-169.254.255.255 (169.254.0.0/16) for Automatic Private IP Addressing. As a result, APIPA provides an address that is guaranteed not to conflict with routable addresses. How to use automatic TCP/IP addressing without a DHCP server
Read / Watch CST3607 Class Outline / Syllabus CCNA Routing and Switching Study Guide 2nd Edition: Chapter 1: Internetworking OSI Reference Model TCP/IP and the OSI Model Explained The OSI Model Demystified [Eli the Computer Guy] Understanding the OSI Reference Model: Cisco Router Training 101 [soundtraining.net]
Do CCNA Routing and Switching Study Guide: Assessment Test p. lvii Chapter 1: Review Questions Note: The answers for the Review Quesions are in Appendix B.
Send me an e-mail, from the e-mail address you check regularly, that I will use to communicate with you for the rest of this semester. Subject: CST3607 Contact Info In the Body of the e-mail: Include your first and last names and your mobile phone number. Note: I will not share your phone number and e-mail address with anyone.
Study the OSI Reference Model Thursday: Aug. 31, 2017
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News Inside the Massive 711 Million Record Onliner Spambot Dump Have i been pwned? It’s About To Get Even Easier to Hide on the Dark Web Worried About Your #Privacy Now? Here's How to Protect It via @Wired
PortaPow Fast Charge + Data Block USB Adaptor Blocks data transfer - your device will not go into 'data transfer' mode if connected to a computer, so you can use a computer just like a mains charger. This also prevents data hacking and any risk of viruses being loaded onto your device when charging from an unknown/public USB socket. Puts your device into fast charge mode - allows you to charge at high speed (upto 2.4A) from a computer USB socket or other USB charger even if it was not originally designed for your device. Most Android and Apple products will charge at double the speed of normal computer USB charging. Available from Amazon.com
Identity Theft is a big problem. Malware is one of the many ways that identity theives can get your personal information. Educatate yourself and your people. IdentityTheft.gov is the federal government’s one-stop resource for identity theft victims. The site provides streamlined checklists and sample letters to guide you through the recovery process. A Life or Death Case of Identity Theft? — Krebs on Security
Protocol Review: DNS (Domain Name System) (or Service or Server) DHCP (Dynamic Host Configuration Protocol) NAT (Network Address Translation) Network Address Translation is an Internet Engineering Task Force (IETF) standard used to allow multiple PCs or devices on a local area network to share a single, globally routable IP address. NAT is also used to avoid address renumbering in a LAN when topology outside the private network changes. ARP (Address Resolution Protocol)
Cisco IOS and Router Command Reference
Unicast, Broadcast, Multicast The Internet Protocol and other network addressing systems recognize three main addressing methodologies: Unicast addressing uses a one-to-one association between the destination address and the network endpoint: each destination address uniquely identifies a single receiver endpoint. Broadcast addressing uses a one-to-many association, datagrams are routed from a single sender to all endpoints, in the broadcast domain, simultaneously in a single transmission. The network automatically replicates datagrams as needed for all network segments (links) that contain an eligible receiver. Multicast addressing is the sending of the same message simultaneously to to multiple endpoints simultaneously in a single transmission, but not to all. The network automatically replicates datagrams as needed for all network segments (links) that contain an eligible receiver.
Collision and Broadcast Domains Collision Domain Broadcast Domain Routers are used to separate broadcast domains How a Broadcast Address Works
Microsoft OneNote OneNote gives users an easily organized, tabbed workspace on which they can type notes, draw, grab links, and insert a variety of media. When connected to a Microsoft account, OneNote data will be synchronized between all your devices. You may already have OneNote is you have Windows 8 or Microsoft Office. Get OneNote for free on all your devices. (Windows, Android, Apple iOS, BlackBerry, Windows Phone, Macintosh OSX) OneNote: No Limits (YouTube) Microsoft OneNote Tutorial (YouTube) OneNote is Office 2010's killer app in education Microsoft OneNote - The best software you'll ever use (YouTube) Cisco Learning Network Free learning resources Cisco certification exam topics CCNA, CCNP study groups Sample CCENT, CCNA, CCNP study questions Career resources IT learning games Community manager support Social learning with IT experts Cisco Exam Preparation - Studying for Results
Wireless Network Security WEP (Wired Equivalent Privacy) : Due to known security issues with WEP encryption, it is recommended that you do not use WEP. WEP can easily be cracked in a few minutes. Wi-Fi Protected Access (WPA and WPA2) When using WPA2, use AES encryption only, instead of TKIP+AES SecurityNow! Episode 170 discusses the TKIP (Temporal Key Integrity Protocol) hack A flaw in a feature added to Wi-Fi, called Wi-Fi Protected Setup, allows WPA and WPA2 security to be bypassed and effectively broken in many situations. WPA and WPA2 security implemented without using the Wi-Fi Protected Setup feature are unaffected by the security vulnerability. Using Wi-Fi Protected Access (WPA) encryption offers individual user isolation, preventing the attacker from decrypting any cookies sent over the network even if they have logged into the network using the same passphrase. Widget Jacking (session hijacking (sidejacking/widgetjacking) attacks) Disconnect.me Privacy-Protecting Add-On Disconnect Now Keeps Your Browsing Safe from Hijacking Easily protect yourself from widget jacking Security Now 386 (Widget Jacking: 1:02:35)
Virtual Private Network (VPN) A virtual private network (VPN) enables users to send and receive data while remaining anonymous and secure online. In the simplest terms, a VPN is used to create a secure, encrypted connection between your computer and a server operated by the VPN service. How to Choose the Best VPN Service for Your Needs (HowToGeek.com) That One Privacy Guy's ? Guide to Choosing the Best VPN (for you) (ThatOnePrivacySite.net) The Best VPN services of 2017 (CNET.com) The Best VPN Services of 2017 (PCMag.com) Which VPN Services Keep You Anonymous in 2017?
Read CCNA R&S Study Guide 2nd Edition: Chapter 2: Ethernet Networking and Data Encapsulation OSI Reference Model {r...} TCP/IP and the OSI Model Explained The OSI Model Demystified [Eli the Computer Guy] Understanding the OSI Reference Model: Cisco Router Training 101 [soundtraining.net] Subnetting and Supernetting IP Addressing and Subnetting for New Users [Cisco.com] Understanding IP Addressing: Everything You Ever Wanted To Know - By 3Com / Chuck Semeria Search Build Your Skills: Subnetting and supernetting IP networks by Jim McIntyre (March 22, 2001) Note: This article excludes subnet zero and the broadcast subnet for the whole address block, but we always include both in our calculations How a Broadcast Address Works
Do CCNA R&S Study Guide 2nd Edition: Chapter 2: Written Labs & Review Questions Until further notice, bring in a stand-alone calculator, (not one on your phone, or computer), to every class. Preferably one that has an Exponent function (^key) ( xy ) If you don't already have a stand-alone calculator, you can pick-up any of the following, or similar, from Staples or Office Depot for $10. Casio FX-260 Solar Scientific Calculator (Staples) Casio FX-260 Solar Scientific Calculator (Office Depot) Texas Instruments TI-30Xa Scientific Calculator (Staples) Sign up for a free Cisco Learning Network account. [A paid membership is not necessary to access a lot of the material]
September Tuesday: Sept. 5, 2017
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News More than 150,000 Internet-facing printers were scanned, located, and used if your router has UPnP enabled, your printers, (or anything else on your network), may have punched a hole through your border router's stateful NAT firewall to make itself "available" to anyone on the public Internet in the world.
QuickTime should be uninstalled from all Microsoft Windows systems Apple will no longer be issuing security updates to QuickTime for the product on the Windows Platform and recommend users uninstall it. Zero Day Initiative has released two advisories ZDI-16-241 and ZDI-16-242 detailing two, critical vulnerabilities affecting QuickTime for Windows. These vulnerabilities will not be patched by Apple. See: US-CERT: Alert (TA16-105A): Apple Ends Support for QuickTime for Windows; New Vulnerabilities Announced Urgent Call to Action: Uninstall QuickTime for Windows Today QuickTime 7 for Windows is no longer supported by Apple. New versions of Windows since 2009 have included support for the key media formats, such as H.264 and AAC, that QuickTime 7 enabled. VLC Media Player will handle any media formats that Windows can't.
2 Factor Authentication Is Your Mobile Carrier Your Weakest Link? : Tips to ensure your mobile device (or, more specifically, your mobile carrier) isn't the weakest link in your security chain. The Value of a Hacked Email Account Two Factor Auth (2FA): List of websites and whether or not they support 2FA. Google Authenticator is a software token that implements two-step verification services using the Time-based One-time Password Algorithm (TOTP) and HMAC-based One-time Password Algorithm (HOTP), for authenticating users.
Panopticlick The Electronic Frontier Foundation (EFF) has online tracker-testing in its Panopticlick, helping you analyze the privacy protections in your Web browser.
Web Browser Plugins NoScript Since so many sites depend on JavaScript, you may want to disable NoScript, but when prompted, leave the other NoScript protections enabled. uBlock Origin Telemetry is an automated communications process by which measurements and other data are collected at remote or inaccessible points and transmitted to receiving equipment for monitoring. When it comes to Windows 10 privacy, don't trust amateur analysts by Ed Bott via ZDNet "Faulty" Windows 10 telemetry network traffic analysis by CheesusCrust "What I have done for this analysis: 4. I have configured the DD-WRT router to drop and log all connection attempts via iptables through the DD-WRT router by Windows 10 Enterprise." When a router drops all connection attempts from a host, what will that host do? Is Windows 10 telemetry a threat to your personal privacy? Windows 10 and telemetry: Time for a simple network analysis [By Simon Bisson | February 15, 2016]
How would you know that a network has been compromised? Network Analyzer/Packet Sniffer Wireshark: Network Analyzer/Packet Sniffer HakTip 64 – How to Capture Packets with Wireshark – Getting Started Introduction to Wireshark Wireshark Display Filters (PacketLife.net) How to Use Wireshark to Capture, Filter and Inspect Packets 5 Killer Tricks to Get the Most Out of Wireshark
Universal Plug-and-Play (UPnP) Disable Universal Plug-and-Play (UPnP) on your router UPnP-enabled routers allow attacks on LANs Report by rapid7.com: SecurityFlawsUPnP.pdf 81 million routers found to have UPnP enabled on their public interfaces. Security Flaws in Universal Plug and Play: Unplug, Don't Play More than 150,000 Internet-facing printers were scanned, located, and used if your router has UPnP enabled, your printers, (or anything else on your network), may have punched a hole through your border router's stateful NAT firewall to make itself "available" to anyone on the public Internet in the world. Check if your router has UPnP, or any other ports/protocols, exposed to the Internet: Go to GRC.com > Services Menu > ShieldsUP! Run GRC's Instant UPnP Exposure Test Run the "All Service Ports" test
Types of Ethernet cabling Straight-through cables are used to connect unlike devices. e.g. Host to Switch, Router to Switch On a host: Pins 1 & 2 are transmit, and 3 & 6 are receive. Crossover cables are used to connect like devices. e.g. Switch to switch, Router to host, Router to Router It is possible to connect switches using a straight-through cable because many switchs have auto configuring ports. Usually referred to as Auto-MDIX. a.k.a. Auto Uplink. Roll-over cables are used to connect a hosts' RS-232 / EIA-TIA-232 serial interface to a routers console port. The default COM port settings for Cisco routers & switches are: Bits per Second: 9600, Data bits: 8, Parity: None, Stop Bits: 1, Flow Control: None
Autonomous System (AS) A group of networks and routers under a common administrative control. Routing inside and autonomous system is referred to as intradomain routing. Routing between autonomous systems is referred to as interdomain routing.
Read CCNA R&S Study Guide 2nd Edition: Chapter 3: Introduction to TCP/IP
Do CCNA R&S Study Guide 2nd Edition: Chapter 3: Written Labs & Review Questions Check if your router has UPnP, or any other ports/protocols, exposed to the Internet: Go to GRC.com > Services Menu > ShieldsUP! Run GRC's Instant UPnP Exposure Test Run GRC's "All Service Ports Test" Report your results at our next class
Thursday: Sept. 7, 2017
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News University attacked by its own vending machines, smart light bulbs & 5,000 IoT devices Verizon published a 4-page PDF describing their incident response in what they term their "Data Breach Digest" Ubiquiti Networks EdgeRouter X: Use a router like this to segment your LAN. e.g. Guest network, Private network, IoT (Internet of Things) network. Each port is a separate network segment. Make sure to immediately update the firmware/EdgeOS Home-Network Implementation: Using the Ubiquiti EdgeRouter X and Ubiquiti AP-AC-LR Access Point by Mike Potts Available from Amazon.com https://www.grc.com/sn/sn-569-notes.pdf About 143m customers affected by massive Equifax cyber incident FTC (Federal Trade Commission) The Equifax Data Breach: What to Do FTC Credit Freeze FAQs Equifax's Instructions Are Confusing. Here's What to Do Now Cybersecurity Incident & Important Consumer Information Freeze your credit files: Equifax, Experian, TransUnion, and Innovis. Request fraud alert for the longest possible time on offer: Equifax, Experian and TransUnion. Check one of your credit reports for free every four months at AnnualCreditReport.com. Instagram hack: Celebrity contact details revealed
Spanning Tree Protocol (STP) Loop avoidance Convergence (on switches) For Layer 2 switches, convergence occurs once the Spanning Tree Protocol (STP) process has completed: i.e. a Root Switch is elected, Root Ports and Designated Ports have been chosen, the Root Ports and Designated Ports have been placed in a forwarding state, and all other ports have been placed in a blocking state. See: Spanning Tree Protocol (STP) Convergence, What is Layer 2 Network Convergence
Cisco's Three-Layer Hierarchical Model Core layer or Backbone Distribution layer Access layer
Dynamic Host Configuration Protocol (DHCP) The process a host uses to get an IP address lease from the DHCP server RFC2131 In addition to an IP address, what additional parameters, if any, does a host need to get from the DHCP server? Subnet Mask Default Gateway DNS Server's IP address Phase
Transmission Method
Discover
Description
broadcast -->
Client requests an IP address. The client broadcasts a DHCPDISCOVER message on the physical subnet to find available servers. The client creates a UDP packet with the broadcast destination of 255.255.255.255 or the subnet broadcast address.
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