||Discussion: Chapter 5 Tour
Video: Professor Messer: Ethernet Standards (7:45)
Activity: Join My Social Circle
Activity: Subnet Problem #4
Assignment: Binary to Hexidecimal Worksheet
Video: YouTube: 100-GIG Fiber Network Media Coverage
- Ethernet operates at layers 1 & 2 of OSI
- There are two ethernet standards
- Two sublayers:
- LLC & MAC (know their role!)
- MAC sublayer has two primary responsibilities (know these!)
- Frame can be broken down into 3 basic categories
- Frame delimiting, Addressing, Error Detection
- Historical progression of Ethernet
- Frame can be further broken down into six fields
Discussion: 188.8.131.52 Ethernet Frame Fields
- Memorize the min-max size of a frame
- Be prepared to describe each of the frame fields
Activities: 184.108.40.206 - 220.127.116.11 Do both activities until you can get them all correct
Lab: 18.104.22.168 Using Wireshark to Examine Ethernet Frames
Assignment: Study Guide 1-14
If you have any extra time, use it to prepare for BPA contests. Contests list is on the CNA shared drive in BPA folder.
Discussion: 22.214.171.124 MAC Address and Hexidecimal
- MAC address is 48 bits long in hexidecimal
- Hexidecimal character represents four bits
- Hexidecimal represented by: Ox, H, or h
- Hexidecimal used for IPv6 (128 bits)
- Know how to covert to/from hexidecimal
Discussion: -126.96.36.199 MAC Address: Ethernet Identity
- OUI - Organizational Unique Identifier
- First three bytes
- MAC addresses MUST be unique in every LAN
Discussion: 188.8.131.52 Frame Processing
- BIA - Burned in Address (ROM chip)
- Can assign MAC in modern devices
- Devices will only receive frames with its MAC, Multicast MAC, Broadcast MAC
Discussion: 184.108.40.206 MAC Address Representation
- MAC address can be represented:
- Using dashes
- Using colons
- Using period
- Use command: ipconfig /all to view MAC address on Windows
- Use command: ifconfig to view MAC on MAC or Linux
Discussion: 220.127.116.11 Unicast MAC Address
Discussion 18.104.22.168 Broacast MAC Address
- 48 ones in binary
Discussion: 22.214.171.124 Multicast MAC Address
- IP (class D) 126.96.36.199 tp 188.8.131.52
- MAC starts with 01-00-5E (OUI portion of address)
(Run through following lab in Packet Tracer first - then send to lab)
Lab: 184.108.40.206 Viewing Network Device MAC Addresses
Assignment: Study Guide 15-24
Homework Assignment: Study for Section 1 Quiz
Quiz: Chapter 5, Section 1
Start Chapter 4: Preventive Maintenance
Discussion: 220.127.116.11 (q. 1)
Discussion: 18.104.22.168 Benefits of Preventive Maintenance (q. 2-4)
- Preventive mainenance decisions based on:
- Computer location or environment
- Computer use
- Preventive maintenance:
- Improves data protection
- Extends the life of the components
- Improves equipment stability
- Reduces the number of equipment failures
Discussion: 22.214.171.124 Preventive Maintenance Tasks (q. 5-7)
- Address tasks for Hardware:
- Remove dust from the power supply.
- Remove dust from the components inside the computer and peripheral equipment, such as printers.
- Clean the mouse, keyboard, and display.
- Check for and secure any loose cables.
- Address tasks for Software:
- Review and install the appropriate security updates.
- Review and install the appropriate software updates.
- Review and install the appropriate driver updates.
- Update the virus definition files.
- Scan for viruses and spyware.
- Remove unwanted or unused programs.
- Scan hard drives for errors.
- Optimize (defragment) hard drives
Discussion: 126.96.36.199 Clean the Case and Internal Components (q. 8-11)
- Heat sink and fan assembly
- Adapter cards
- Power supply
- Internal drives
Discussion: 188.8.131.52 Inspect the Internal Components (q. 12-13)
Discussion: 184.108.40.206 Environmetal Concerns (q. 14-15)
- Allow devices to warm/cool before operating them
Assignment: Chapter 4 Study Guide 1-15
- Don't leave in auto outside
- Condensation can short circuits
Study for Chapter 4, Section 1 Quiz
Quiz: Chapter 4, Section 1
Section 2: Intro to Troubleshooting
Video: Professor Messer: Troubleshooting Common Hardware Problems (15:19)
Discussion: 220.127.116.11 Intro to Troubleshooting Process (q. 16-23)
- Many companies require computer owner to sign liability waiver or pay for backup
- Can be sued for great sums of money
Discussion 18.104.22.168 Step 1: Identify the Problem (q. 24-34)
- Conversation Etiquette
- Open/Closed type questions
- Documenting responses
- Beep Codes
- BIOS Information
- Event Viewer
- Device Manager
- Task Manager
- Diagnostic Tools
Activity: 22.214.171.124 Identify the Problem (make sure you can use open/closed ?'s with ease!)
Discussion: 126.96.36.199 Step 2: Establish a Theory of Probable Cause (q. 35-37)
Discussion 188.8.131.52 Step 3: Test the Theory to Determine Cause (q. 38-39)
Discussion 184.108.40.206 Step 4: Establish a Plan to Implement the Solution (q. 40)
Discussion: 220.127.116.11 Step 5: Verify Full System Functionality (q. 41-42)
Discussion 18.104.22.168 Step 6: Document the Findings (q. 43-46)
Discussion 22.214.171.124 Common PC Problems and Solutions (q. 47-52)
Discussion 126.96.36.199 Summary (q. 53)
Assignment: Chapter 4 Study Guide 16-53 Finish
Homework: Study for Chapter 4 Test
Discussion: 188.8.131.52 Switch Fundamentals (q. 25)
- Switch and bridges are layer 2 devices
- Uses MAC address table to make forwarding decisions
- MAC address table is empty when switch first turned on
- Must learn mac addresses of attached devices
- MAC address table is sometimes called CAM table or switching table.
Discussion: 184.108.40.206 Learning MAC Addresses (q. 26)
- MAC address table is empty at switch start-up
- MAC address table is filled in by inspection of SOURCE MAC ADDRESS of frame
- If address is already there, the timer is refreshed. by default 5 minutes.
- If destination MAC address is unknown, switch floods frame out of all ports except one received on.
- If destination is broadcast or multicast, is also sent out all ports except incoming port.
Discussion: 220.127.116.11 Filtering Frames
- As MAC table becomes populated with MAC addresses, switch can direct frames to specific interfaces by matching destination MAC addresses with table entries.
- This allows multiple connections at the same time.
- Conserves bandwidth for other uses/connections.
Video 18.104.22.168 MAC Address Tables (3:09)
Video 22.214.171.124 Sending a Frame to the Default Gateway (3:01) (q. 27)
Activity 126.96.36.199 Switch It! PRACTICE UNTIL YOU ARE AN EXPERT AT THIS!!!!
- This is the best learning tool in the entire academy
- Slight learning curve to use it
- Make sure you can predict switch operations with ease!!
- Keep practicing until you have done all the problems - about 20 of them
||Turn in study guide
Test: Chapter 4
Lab: 188.8.131.52 Viewing the Switch MAC Address Table
Discussion: 184.108.40.206 Frame Forwarding Methods on Cisco Switches (q. 28)
- Two forms of switching can be used:
- Store-and-forward switching
- Cut-through switching
- Store-and-forward uses CRC (is value of algorithim of bit 1's in the frame)
- Store-and-forward is required for QOS communication
- If lots of errors, switches can dynamically set themselves for Store-and-Forward
Discussion 220.127.116.11 Cut-Through Switching (q. 29)
- Cut-through uses one of two methods:
- Fast-forward switching
- Sends as soon as destination MAC learned
- Fragment-free switching
- Sends as soon as destibation MAC learned, and
- That the frame is at least 64 bytes long
Discussion 18.104.22.168 Memory Buffering on Switches (q. 30)
- Switches can buffer frames when there is end device congestion
- Such as NIC speed is slower than switch port speed
- Two types of switch buffering:
- Port-based Memory Buffering
- Shared Memory Buffering
Activity 22.214.171.124 (1 & 2) Frame Forwarding Methods
Discussion: 126.96.36.199 Duplex and Speed Settings (q. 32-35)
- Two common settings each port:
- Usually set to dynamically learn on own
- Error condition can be a Duplex Mismatch. User experiences slow connection.
Discussion: 188.8.131.52 Auto-MDIX (q. 36)
- Do not rely on Auto-MDIX
- Networkers MUST know and use correct cables.
Assignment: Study Guide 25-41
Homework: Study for Section 2 Quiz
Quiz: Section 2
Discussion: 184.108.40.206 Destination on Same Network
- Hosts use combo of IP address & subnet mask to determine destination local or remote
- All frames contain source & destination MAC and IP address.
- Local destination is on same network
Discussion: 220.127.116.11 Destination Remote Network
- Remote destination is when the IP/subnet mask combo are on another network
- Packets are sent to the default gatreway of the router
PT: 18.104.22.168 Identify MAC and IP Addresses (30 min)
Discussion 22.214.171.124 Introduction to ARP
- ARP - Address Resolution Protocol
- Destination IP are generally known (by virtue of DNS). Not so for MAC addresses.
- ARP discovers what destination MAC is associated with destination IP address.
- ARP maintains table of IP to MAC address mappings.
Discussion 126.96.36.199 ARP Functions
- When destination MAC isn't already known, ARP discovers with an ARP request packet
- Only host recognizing own IP address responds to ARP request
- Sends its MAC address back to sending host.
- If destination is on another network, the default gateway sends its MAC address instead.
- The ARP table remembers (caches) these learned MAC/IP combo addresses for a time.
Video 188.8.131.52 ARP Request (2:55)
- ARP requests don't have a destination MAC address because MAC address isn't known at this point. Destination MAC address field is empty.
- ARP requests are broadcast and use destination MAC address of all F's.
- ARP frames have a TYPE field value of Ox806 (can see it in Wireshark)
- Routers DO NOT send out broadcasts.
Video 184.108.40.206 ARP Reply (1:57)
- Only the device recognizing own IP address responds to ARP request.
- Sends back its MAC address using unicast.
- If no response, frame is dropped.
- Similar process in IPv6 environment.
Video 220.127.116.11 ARP Role in Remote Communication (3:02)
- In remote communications, the default gateway sends back MAC to sending host.
Discussion 18.104.22.168 Removing Entries from an ARP Table
- You can clear ARP table entries manually.
- ARP entries are normally only saved for two minutes and then flushed.
Discussion 22.214.171.124 ARP Tables
- To view ARP table in Windows, use arp -a command.
- To view ARP table in a router, use show ip arp command.
Assignment: Study Guide 44 (Turn in today)
Review Video: CBTNugg 100-101 #09 Welcome to the World of Switching (33:55)
PT: 126.96.36.199 Examine ARP Table
Discussion 188.8.131.52 ARP Broadcasts
- ARP broadcasts add to early morning network congestion
Discussion 184.108.40.206 ARP Spoofing
- ARP creates a security vulnerability called ARP Spoofing/ARP Poisoning
- Attacker responds to ARP requests with own MAC address to capture frames
- This is one of the dangers of rogue routers on networks
- Can also be used in DOS attack
Video: YouTube: How Switches Learn MAC Addresses
Activity: 220.127.116.11 MAC and Choose. (Disregard collecting three old pictures.View them, but don't print them out please)
Discussion 18.104.22.168 Summary
Resource: Fields of a Frame
Video: Cisco Netacad Routing and Switching v6.0 - Chapter 5 (20:10)
Activity: Distribute Chapter 5 Test Study
Assignment: Finish Chapt 5 Study Guide
Homework Assignment: Study for Chapter 5 Test
||2nd Grading Period Binder Due
Discussion: 22.214.171.124 Summary
Test Chapter 5
||Start Chapter 7
Hand out Chapter 7 Study Guides
Assignment: Chapter 7 Study Guide 1-27
Chapt 1-5 Midterm Exam
Make up & BPA Prep
||Turn in binders
Chapt 1-4 Midterm Exam
||Turn in binders
Make up & BPA Prep
CCNA Chapter 5 Review PowerPoint
A+ Chapter 4 Review PowerPoint
IP Addressing and Subnetting for New Users
What is APIPA?