network+ exam

What to know:

1. Multiple choice practice questions are good, do as many as you can. 
2. THERE ARE SIMULATIONS ON THE EXAM. 
• These simulations describe a scenario that you need to fix, what they don't do is give you operating instructions for the simulations themselves. 

Concepts to Study

• OSI Model, there are very few TCP/IP model questions 
• psychical network configuration 
• know cable ratings, their color, and their properties, their usage 
• Know important protocols & port numbers and their functions 
• Be Able To:
• compare the layers of the OSI and TCP/IP models
• Know all of the layers, the order they go in, and their fuctions 
• Classify how applications, devices, and protocols relate to the OSI model layers
• i.e. switches, routers, servers, etc. 
• Explain the purpose and properties of routing and switching
• identify common TCP and UDP default ports 
• explain the function of common networking protocols 
• 
  
• given a scenario, implement the following network troubleshooting methodology 
• idenfify virtual network components 
• in a digital model, identify  the router, switch, etc.
• Given a scenario, install and configure routers and switches
• given a scenario, install and configure a wireless network
• given a scenario, troubleshoot common wireless problems given a scenario, troubleshot common router and switch problems 
• given a scenario and a set of requirements, plan and implement a basic SOHO network 
• categorize and contrast different wireless standards 
• categorize WAN technology types and properties 
• given a scenario, troubleshoot common physical connectivity problems
• identify components of wiring distribution
• explain the purpose and features of various network applicances
• given a scenario use appropriate hardware tools to troubleshoot connectivity issues 
• given a scenario use appropriate software tools to troubleshoot connectivity issues 
• given a scenario use the appropriate network monitoring resource to anaylze traffic
• explain different methods and rationales for network performance
• given a scenario, implement appropriate wireless security measures
• explain the methods of network access security 
• explain methods of user authentication
• explain common threats vulnerabilities and mitigation techniques 
• given a scenario install and configure a basic firewall
• categorize different types of network secuiryt appliances and methods 

Exam Tomorrow!!

Network Topologies 

1. Bus
• simplest topology 
• nodes of the network are individually linked up to two successive other nodes or another node and a terminating node (terminator)  
• considered archaic 
• difficult to troubleshoot network issues
• redundancy issues 
• need for terminators 
• amount of traffic created 
• nodes linked in this topology are called "daisy-chained"
2. Ring 
• similar to bus network in that nodes are linked to each other 
• ends of a ring network are not terminated because there are no ends
• a "circular" network in which each and every node is linked to two other nodes 
• shares many of the same weaknesses as the bus topology 
• troubleshooting difficult
• redundancy 
• traffic 
• difficulty of adding a node to a token ring network
3. Star
• most typical and practical network setup 
• each node maintains an individual connection to the switch 
• traffic between each node only goes through the switch and not through other nodes 
• increases redundancy of the network 
• increases data privacy 
• reliant on the switch 
• extensive wiring necessary
4. Mesh/Ad-Hoc
• rarely occurring configuation in which every node is connected to every other node 
• usually only occurs in wireless networks in "ad hoc" mode 
• each wireless card maintains a connection to ech other wireless node it wish to connect with 
• is inefficient and requires a large amount of overhead and is difficult to manage
5. Combined/Hybrid 
• a topology referring to the case where more than one topology is utilized 

Types of networks(Access Models)

1. Decentralized
• often referred to as "peer to peer" network 
• does not contain any distinctions between client and server 
• every node acts as a client and/or server depending on the task at hand
• difficult to maintain (each node must be manually configured, updated, maintained individually)
2. Client-Server Access
• nodes can either act as "clients' or as "servers" 
• management is easy
• network can offer services that decentralized networks cannot 
3. Centralized
• a modified client-server network in which clients have no individual control 
• all maintenance and setup occurs at the server level 

Network+ Review

1. What type of fiber commonly uses lasers as a transmission source?
• Single-Mode Fiber  is used for laser trasmission
• Multi-Mode Fiber is used for LED most commonly 
• large-core fiber is another name to multi-mode fiber 
2. Is distance the only advantage in using single-mode over multi-mode fiber-optic cable?
• Multi-Mode Fiber
• short range communication (up to 2 km) 
• does not use lasers, most commonly uses LED 
• inexpensive light source 
• uses an orange color cable 
• called multi-mode because light can take more than one path through the cable 
• single-mode fiber
• small core 
• light only takes one path 
• up to 100km without processing
• most commonly uses laser light 
• normally a yellow cable color
• Short Answer, YES.
3. What is the difference between a logical and a physical network topologies?

• Completely different forms of documenting a network
• physical network layout
• 
• shows routers, servers, other connections 
• main issue is determining what subnet things are on 
• devices in a physical map can be on completely different networks 
• used for troubleshooting physical issues (i.e. cabling and conections)
• Logical network diagram 
• 
• you can see the routing paths 
• used for troubleshooting data connections
• given subnets 
• identifies location routers 

Media Converters

Media Converters 

• used to convert from one form of media to another
• most typical is to convert between copper cabling and fiber optic cabling 

CSU/DSU

• Channel Service Unit/Data Service Unit 
• a hardware device which converts data frames used on a LAN into data frames uesd on a WAN
• typically used to connect a T1 line to a local network

Network+

Load Balancer

• Load balancers are used when there are more than one line of communication available
• help to divide communication evenly between the different communication lines
• a form of clustering
• where you have more than one server servicing clients 

Bandwidth Shaper 

• used to help make communication more efficient
• provide a much higer level of control over what data gets sent where and when 
• can limit what data gets sent at what time 
• also known as bandwidth throttling 

Understanding IPv6 routing

Understanding Why IPv6 was Created 

• Limitations of IPv4
• IPv4 has been in use since 1981
• introduced and detailed in RFC 791 
• no substantial updates/improvements
• Exhaustion of IPv4 Address Space
• Explosive growth of the commercial internet
• proliferation of IP-enables devices (smartphones, tablets, etc)
• short-term solutions
• CIDR Classless Interdomain Routing
• NAT Network Address Translation 
• Private Addressing
• Integrated Security
• Original IPv4 specification did not indentify any security mechanisms
• IPsec was a later addition to IP 
• Scalability
• even with CIDR a typical BGP routing table is enormous 
• AT&T route server lists around 373,800 prefixes
• governments are mandating IPv6 adoption
• Benefits of IPv6 Improvements
• Vast Address Space
• 128 bit addressing (as opposed to 32 bit)
• addressing space is about 340 trillion addresses
• Address Assignment
• ability of a device to detect/create its own address
• advanced DHCP and auto-configuration features 
• Global Address Aggregation
• Hierarchical structure

Troubleshooting OSPF: Show Commands and Debug Commands

Relevant Debug and Show Commands 

1. OSPF Show Commands
2. OSPF Debug Commands 

OSPF Show Commands

• Show IP Protocols 
• Data Displayed by the command:
• OSPF Status and process-id
• area types configured
• protocols being redistributed
• networks being advertised
• neighbors/gateways
• helpful in troubleshooting:
• neighbor relationships
• missing routes
• summarization issues 
• filtering problems 
• Show IP route OSPF
• Data Displayed by the Command;
• OSPF routes from neigbors
• administrative distance
• cumulative cost metric
• route source/interface
• helpful in troubleshooting:
• missing routes 
• summarization issues 
• filtering problems
• general troubleshooting 
• Show IP OSPF Interfaces
• Data Displayed:
• Interfaces participating in OSPF
• Network Type(s)
• Neighbor count
• Authentication Type
• Timer Values
• Helpful in troubleshooting:
• neighbor relationships
• local congiuration issues
• routing problems
• Show IP OSPF Neighbors
• data displayed:
• Active fully adjacent neighbors
• router ID of neighbors
• IP address/interface of neighbors
• dead time of neighbors
• neighbor state/DR state (designated router state)
• Helpful for;
• Neighbor relationships
• local configuration issues
• Show IP OSPF Database
• Data Displayed:
• LSA types Per area
• Advertising router
• Link ID(Subnet)
• age
• Helpful For:
• Missing Routes
• Filtering Problems
• General troubleshooting 

How to Configure an IP Address: Windows

1. Start
1. Control Center
2. Network & Internet 
3. Network Connections
2. Local Area Connection 
1. right click properties
2. ipv4 properties (this is where you configure without DHCP)

General: 

1. Give it an IP (Either automatically or manually)
1. Give it a subnet Mask
2. give it a default gateway
2. establish a DNS server addresses (either automatically or manually)
1. give it a preferred DNS server
2. give it an alternate DNS server

Alternate Configuration: 

1. Click APIPA (Automatic Private IP address)
2. OR User Configured (Static) as a backup
1. configure for critical machines 
1. allows the ability to troubleshoot if there are network issues 

Net+ Exam

I have successfully registered for the network+ certification exam. I chose the date June 4th at 10am.

:D

Net+ Registration

Everything was working fine and then....


The voucher didn't work. 

Chapter 11: TCP/IP Security Pg 382

TACAS+ 

• Terminal Access Controller Access Control System Plus 
• a proprietary protocol developed by Cisco to support AAA in a network with many routers and switches
• uses TCP port 49 by default 
• separates authorization, authentication, and accountin into different parts 
• uses PAP, CHAP, md5 hashes, and Kerberos to authenticate 

Kerberos 

• an authentication protocol that has no connection to PPP 
• use for TCP/IP networks with many clients all connected to a single authenticating server 
• Key Distribution Center (KDC) 
• Authentication Server (AS)
• Ticket Granting Service (TGS)
• installed on the domain controller
• the client sends a request that includes a hash of the user name and password to the AS 
• the AS compares the results 

Net+ Practice Exam 7

Test Taken

Score: 76%

What to Remember:

1. The preamble of an Ethernet frame is 7 bytes.

Sources:
Registered Ports
OSI Model
Ethernet Frame
File Transfer Protocol
Network Topologies
Challenge Handshake Authentication Protocol
Digital Signatures
Virtual Private Network
Message Digest Algorithm
Remote Copy
Remote Shell
Cyclic Redundancy Check  

Net+ Practice Exam

Test Taken 
Score: 52%

Things To Remember:

1. SSH file Transfer protocol and Secure Copy allow for secure file transfer. 
2. In routing, the route with the lowest metric is the preferred route.
3. Smartjack provides an ISP with a troubleshooting tool for testing connection at the customer site without the need of sending a technician to that site. 
4. Transmission Control Protocol (TCP) features three-way handshake and re-transmission of lost packets.
5. User Datagram Protocol (UDP) is commonly used for streaming audio and video and offers fasters transfer speed than TCP.
6. Firewall reconfiguration is an example of an active response by an IPS.
7. An IDS can send alerts and log events.

List of Assigned Ports

Net+ Practice Exam

Test Taken
Score: 36%

Things To Remember:

1. Interference between two pairs in a cable measured at the same end of the cable as the signal source is called NEXT
2. Interference between two pairs of cables measured at the other end of the cable from the signal source is called FEXT
3. An IP address consists of a network ID and a host ID
4. A MAC address consists of an OUI and a device ID 
5. Trivial File Transfer Protocol (TFTP) uses UDP port 69
6. Simple Mail Transfer Protocol (SMTP) is used for relaying e-mail messages between mail servers  and runs on TCP port 25. Ports 110 and 143 need to be open in order to retrieve an e-mail from SMTP server. 
7. Reverse Address Resolution Protocol (RARP) does MAC to IP resolution 
8. Port numbers are divided into 3 ranges. 
9. HTTPS runs on TCP port 443

Network+ Practice Exam

Test Taken

Score: 28%

Things To Remember;

1. 802.11i is the IEEE standard that specifies security mechanisms for wireless networks.
2. WPA2 uses AES encryption, is known as a Robust Security Network(RSN) and uses block encryption cipher. 
3. MAC address filtering and RADIUS can be used to enhance wireless network security.
4. DSSS, OFDM, AND FHSS are wireless broadcasting methods. 
5. SHA-1 and MD5 are cryptographic has functions. 
6. nbstat -n lists local NetBIOS names.
7. TTL describes the maximum time an IP packet can exist in a network. Every device process an IP packet must decrease the TTL value by at least 1. If the TTL field value reaches 0 while an IP packet is still on the way to its destination, the IP packet is considered deliverable and must be discarded. 

Network+ Practice Test

Test Taken

Score: 44%

What To Remember;

1. The TCP port used by Point-to-Point Tunneling Protocol is 1723
2. Asynchronous Transfer Mode (ATM) encodes data into cells 
3. DOCSIS is a cable modem standard
4. Public Switched Telephone Network (PSTN) is also commonly referred to as POTS
5. Faults in fiber-optic cabling can be located with the use of OTDR. 
6. netstat -o displays the process ID for each connection
7. E1 lines run at a speed of 2.048 Mbps
8. A packet sniffer can be used to analyze network traffic
9. 802.1Q is a VLAN standard
10. E3 lines run at the speed of 34.368 Mbps
11. Wireless broadband solution defined in the IEEE 802.16 standard is also referred to as WiMAX
12. An Ethernet cable terminated on both ends according to the TI/EIA-568-A standard or the TIA/EIA-568-B is a patch cable.

Practice Exam - Network+

Test Taken

Score 36%

What to Remember;

1. Address Resolution Protocol (ARP) provides IP to MAC resolution.
2. /24 subnet mask has 24 leading 1s in binary.
3. IP address from the 169.254/16 range may indicated problems with DHCP
4. To get a new DHCP release on Windows type the commands: ipconfig /release and ipconfig/renew
5. UDP port 67 is used by DHCP and bootstrap protocol
6. VLAN based on ports can be called a static VLAN
7. VLAN based on MAC addresses could be called a dynamic VLAN
8. Modems convert analog signals to digitals and vice versa.
9. DS0 signal rate has a value of 64 kbits
10. The DNS record AAAA is an IPv6 record
11. RC4 is used  to provide encryption in WEP 

Chapter 11: Security TCP/IP Pg 375 - 382

Authorization

• Access Control List (ACL): a clearly defined list of permissions that specify what an authenticated user may perform on a shared resource
• ACL Access Models;
• mandatory
• discretionary
• role based
• Mandatory Access Control (MAC): every resource is assigned a label that defines its secuiryt level
• used to define what privileges programs have to other programs stored in RAM
• oldest and least common of the three ACL access models
• Discretionary Access Control(DAC): based on the idea that a resource has an owner who may at his or her discretion assign access to that resource 
• Role-based Access Control (RBAC): defines a user's access to a resource based on the roles that the user plays in the network environment
• creates groups 

PPP

• Point-to-Point Protocol (PPP): enables two point-to-point devices to connect, authenticate with a user name and password, and negotiate the network protocol the two devices will use
• is not Ethernet but still can support TCP/IP
• Five distinct phases to a PPP connection:
• Link Dead: Means that the modem is turned off. Link control Protocol(LCP) will start the connection.
• Link Establishment: LCP will establish a connection 
• Authentication
• Network layer Protocol: LCP uses network control Protocol (NCP) to make the proper connections for the protocol.
• Termination: LCP will timeout and terminate
• Initiator: the side asking for the connection
• Authenticator: the side with the list of user names and passwords
• PPP came with two ways to authenticate a user name and password:
• Password Authentication Protocol (PAP): transmits the user name and password over the connection in plaintext
• anyone who can tap the connection can learn the user name and password
• Challenge Handshake Authentication Protocol (CHAP): relies on hashes based on a shared secret, usually a password both ends know
• periodically repats the entire authentication process 
• prevents man-in-the-middle attacks 

AAA

• Authentication, Authorization, and Accounting (AAA): designed for port authentication 

Radius

• Radius Authentication Dial-In User Service (RADIUS): was created to support ISPs with to connect modems to computers to a single central database 
• Consists of three devices:
• the server that has access to a database of user names and passwords 
• Network Access Servers (NASs)
• a group of systems that dial into the network 
• a single server can support multiple NASs and provide a complete PPP connection from the requesting system 

Chapter 11: Securing TCP/IP Pg 368 - 375

Encryption and the OSI Model 

• Layer 1: No common encryption done at this layer
• Layer 2: A common Place for encryption use proprietary encryption devices. These boxes scramble all of the data in an Ethernet frame except the MAC address information. Devices or programs encode and decode the information on-the-fly at each end. 
• Layer 3: Only one common protocol encrypts at lyaer 3: IPsec. IP sec is typically done via software that takes the IP packet and encrypts everything insdie the packet, leaving only the IP addresses and a few other fields unencrypted. 
• Layer 4: Neither TCP nor UDP offers any encryption methods 
• Layers 6 and 6: Not common layers for encryption
• Layer 7: many  applications use their own encryption, placing them squarely in layer 7. 

Nonrepudiation 

• simple means that the receiver of information is confident the sender is authentic 

Hash 

• Cyrptographic Hash Function: a mathematical function that you run on a string of binary digits of any length that results in a value of some fixed length 
• Also known as a hash
• output is known as a checksum or a digest
• it is a one-way function which means it is irreversible
• should not be able to re-create the data 
• should have a unique checksum for any two different input streams 
• used most commonly to encrypt files 
• Message-Digest Algorithm version 5 (MD5) 
• Challenge-Response Authentication Mechanism-Message Digest 5(CRAM-MD5)
• a tool for server authentication 

Digital Signatures 

• Digital Signature: a string of ones and zeroes that can only be generated by the sender 

PKI

• certifcate: a standardized type of digital signature that includes the digital signature of a third party 
• public-key certificate: an electronic document that uses a digital signature to bind a public key with an identity

Chapter 11: Securing TCP/IP Pg 359 - 368

Making TCP/IP Secure

• Four Areas:
• Encryption
• to scramble, mix up, or change the data in such a way that makes certain people unable to read it
• Nonrepudiation
• the process that guarantees that the data is the same as orginally sent and that it came from the source you think it should have come from 
• authentication
• to verify that whoever accesses the data is the person you want accessing that data 
• authorization 
• defines what a person accessing the data can do with that data 

Encryption

• plaintext: data is in an easily read or viewed industry-wide standard form 
• also referred to as cleartext 
• cipher: a series of complex and hard to reverse mathematics you run on a string of ones and zeroes to make an new set of seeming meaningless ones and zeros 
• complete algorithm: the method used to implement a cipher
• symmetric-key algorithm: any encryption that uses the same key for both encryption and decryption 

Symmetric-Key Algorithm Standards

• most algorithms are called block ciphers because they encrypt data in single chunks
• work well when data comes in clearly discrete chunks
• stream cipher: takes a single bit at a time and encrypts quickly
• Data Encryption Standard(DES)
• used a 64-bit block and a 56-bit block key 
• Rivest Cipher 4(RC4): 
• Advanced Encryption Standard (AES)
• a block cipher 
• uses 128-bit block size
• uses 128-, 192-, and 256-bit key size

Asymmetric-Key Algorithm Standards

• Public-Key Crytography:
• allowed keys to be exchanged securely
• Ribest shamir Adleman(RSA)
• fully functional algorithm that enabled secure digital signatures

Chapter 10: Network Naming Pg 349 - End

WINS

• LMHOSTS: 
• contains a list of the NetBIOS names and corresponding IP addresses of the hos systems on the network 
• work exactly the same as the DNS HOSTS file
• WINS: Windows Internet Name Service
• let NetBIOS hosts register their names with just the one server
• eliminates the need for broadcasting and thereby reducing NetBIOS overhead substantially
• enables NetBIOS name resolution across routers
• enables NetBIOS to function in a routed network 
• WINS Proxy Agent: 
• forwards WINS broadcasts to a WINS server on the other side of the router

Configuring WINS Clients

• configure the IP address of a WINS server in its WINS settings under Network Properties
• windows system will look for a WINS server to register its NetBIOS name 
• if it finds a WINS server, it will register its NetBIOS name to the WINS server
• if it doesn't it will automatically start broadcasting its NetBIOS name 
• you can add WINS information to DHCP if necessary

Troubleshooting WINS

• most WINS problems are NetBIOS problems
• most common problem is having two systems share the same name
• can use nbstat to help deal with NetBIOS problems 
• -c switch tells nbstat to check the current NetBIOS name cache 

Diagnosing TCP/IP Networks

• most TCP/IP problems come from improper configuartion 
• use the same steps no matter what the error 
• check the network connetions and protocols
• Steps:
• Diagnose the NIC: use ping with the loopback address to determine if the system can send an receive packets
• type ping 127.0.0.1 or ping localhost 
• if you get an error, check the NICs driver and replace it if necessary
• Diagnose Locally: ping a few neighboring systems by both IP address and DNS name
• use the net view command to see if the other local systems are visible 
• if you can't ping by DNS, check the DNS settings
• if you can't see the network using net view you may have a problem with your NetBIOS settings 
• Check IP address and subnet mask: ensure you have the right IP address and subnet mask. If using DHCP, renew the lease. 
• Run netstat: run netstat with no options at all and with the -s option. Running netstat with no options shows all the current connections to the sytem. 
• Run netstat -s: Displays several statistics that can help diagnose problems. If the display shows you are sending but not receiving, it is likely that there is a broken network cable.
• Diagnose to the Gateway: Ping the local interface and then the one to the internet. If you can't ping the router, it is either down or there is no connection to it. 
• Diagnose to the Internet: Ping an address on the internet, try several if the first one does not work. run tracert to mark out the entire route the ping packet traveled between you and whatever you were trying to ping. 

Things to Remember:

1. netBIOS uses a flat name space whereas DNS servers use a hierarchial name space.
2. the DNS root directory is represented by a dot (.)
3. To see the DNS cache on a Windows system, run the command ipconfig /displaydns at the command prompt. 
4. The HOSTS file is checked first when trying to resolve to FQDN to IP address.
5. The MX record is used by mail servers to determine where to send e-mail
6. the command ipconfig /flushdns eliminates the DNS cache.
7. the tool to use for querying DNS server functions is nslookup.
8. A DNS server stores the IP addresses and FQDNs for the computers within a domain in the forward lookup zone.  

Chapter 10: Network Naming Pg 346 - 349

DNS Security Extensions

• querying a DNS server gives you a list of every computer name and IP address that it serves
• DNS Security Extensions (DNSSEC) - a set of authentication and authorization specifications designed to prevent impersonations of DNS servers 
• implemented through extension mechanism for DNS (EDNS)
• a specifcation that expands several parameter sizes 

Troubleshooting DNS

• most DNS problems result from a problem with the client systems
• run ipconfig /flushdns on windows to eliminate any DNS caches on the local system
• ping
• run ping with the name of a well-known website
• if you get a "server not found error" run ping using just the IP address
• if ping works with the IP address but not with the web site name, you have a DNS problem
• once a problem with DNS is discovered, check to make sure the system has the correct DNS server entry
• run ipconfig /all to see if those DNS settings are the same as the ones in the server 
• if they aren't, refresh the DHCP settings 
• if the correct DNS settings for the DNS server and the DNS settings in ipconfig /all math those settings, the problem is with the DNS server itself
• nslookup (Name Server Lookup) enables DNS server queries
• allows the query of all types of information from a DNS server and change the system uses DNS
• running nslookup outputs an IP address and the name of the default DNS server
• 
  

Chapter 10: Network Naming Pg 341 - 346

CIFS

• a computer uses a CIFS broadcast to get the name of another computer
• organizes computers on a network into groups
• workgroup: a name that organizes a group of computers
• all computers within a domain authenticate to the domain controller when they log in 
• Active Directory: an organization of related computers that shares one ore more windows domains
• has no single domain controller

Chapter 10: Network Naming pg 326 - 340

Name Servers

• DNS Server: a computer running DNS sever software
• zone: a container for a single domain that gets filled with records
• record: a line in the line zone data that maps an FQDN to an IP address 
• systems running DNS server software store the DNS information
• when a system needs to know the IP address for a specifc FQDN, it queries the DNS server listed in the TCP/IP configuration
• Authoritative DNS server: a simple network usually has one DNS server for the entire network
• job is to make sure that all the other name servers are updated for changes
• a DNS server has a signle zone that lists all the host names on the domain and their corresponding IP addresses
• a single DNS domain may have a single authoritative DNS server but a number of other DNS servers 

Name Resolution

• a web browser must resolve the name to the web server's IP address to make a connection to that web server
• can be resolved in three ways
• broadcasting
• consulting the locally stored HOSTS text file
• contacting a DNS server
• to broadcast, the host sends a message to all the machines on the network 
• works for small networks 
• limited because it cannot provide name resolution across routers
• routers do not forward broadcast messages to other networks
• a HOSTS file lists the names and addresses of machines on a network 

Network + Practice Exam

Test Taken
Score Given: 6/25

Things To Remember:

1. nslooup is used for querying DNS servers to obtain domain name or IP address mapping
2. HTTPS uses SSL/TLS on TCP port 443
3. In transport mode, IPsec offers encryption.
4. TCP port 20 is used for FTP data transfer.
5. Coaxial cabling is used with BNC connectors.
6. IPv6 addresses consist of 128 bits.
7. Layer 2 tunneling Protocol offers no encryptions used with IPsecruns over UDP port 1701
8. Network Time Protocol uses UDP port 123
9. Smurf attack is an example of a Distributed Denial of Service attack.
10. CSMA/CA is the name of an access method used in wireless networks.
11. Fake logon screen on a system will most probably be a result of downloading and installing a trojan horse.
12. Internet Group Management Protocol is used for establishing multicast group memberships used on IPv4 networks.
13. IMAP4 runs on TCP 143 and is used for retrieving e-mail messages from e-mail servers.
14. MAC address's consist of 48 bits and is also known as a physical address.
15. CSMA/CD is used as an access method used in ethernet networks.
16. 802.3ae defines 10 Gigabit Ethernet

Chapter 10: Network Naming pg 317 - 322

How DNS Works 
- DNS servers use UDP port 53 and sometimes TCP port 53
- the DNS root for the entire internet consists of 13 powerful DNS server clusters all over the world
        -> has the complete definitive name resolution table
- Internet Corporation for Assigned Names and Numbers (ICANN): creates new TLDs 

Name Spaces 
- Hierarchical Name Space (used by DNS): an imaginary tree structure for possible names that can be used within a single system
       -> enables administrators to give networked systems longer names
- Flat Name Space (used by HOSTS): an undivided list containing all names
       -> all names must be absolutely unique

Chapter 9: TCP/IP Applications Pg 301 - End

Rlogin, RSH, and RCP
- Remote Login (Rlogin): you can connect and run commands by running the program with the host name of the server
       -> can configure it to log in automatically without needing to enter a username and password
       -> only connects using UNIX hosts
- Remote Shell (RSH): enables you to send single commands to the remote server
        -> runs over TCP port 514 by default
- Remote Copy Protocol (RCP): provides the capability to copy files to and from the remote server without needing FTP or NFS 

SMTP, POP3, AND IMAP4
- Simple Mail Transfer Protocol (SMTP): used to send e-mail
- Post Office Protocol 3 (POP3): receives e-mail from SMPT using TCP port 110
- Internet Message Access Protocol 4 (IMAP4): retrieves e-mail from an e-mail server
         -> enables you to search through your messages on the mail server to find specific keywords
         -> supports the concept of folders
       
File Transfer Protocol (FTP)
- original protocol used on the internet for transferring files
- can transfer while keeping security and data integrity
- uses TCP ports 21 and 20 by default

Things To Remember: 

1. Secure Sockets Layer (SSL) is a protocol developed by Netscape for transmitting private documents over the internet. SSL works by using a public key to encrypt sensitive data.
2. URLs that use an SSL connection start with HTTPS 
3. SSH encrypts data and is more secure than Telnet. SSH uses port 22.
4. Telnet is used to issue commands to a remote server

Chapter 9: TCP/IP Applications pg 286 - 300

Connection Status 
- open port: a socket that is prepared to respond to any IP Packets destined for that socket's port number
           -> every application has an open port
           -> to see all listening ports time netstat -an into a command prompt

Rules for Determining Good vs. Bad Communications

1. Memorize known ports for common TCP/IP applications 
2. Learn netstat such as -an, -n, -o, and -b
3. get rid of bad or unnecessary processes 

The World Wide Web

- composed of servers that s tore specially formatted documents using Hypertext Markup Language (HTML)

        -> many pages now are written using HTML5

- Extensible Markup Language (XML): provides the basic format or language for everything from application programming interfaces to word documents

HTTP

- Hypertext Transfer Protocol (HTTP): underlying protocol used by the web 

           -> relays commands executed by users without reference to any commands previously executed

Web Servers and Web Clients

- web server: a computer that delivers web pages

           -> listen on port 80 

- Internet Information Services (IIS): enables you to set a maximum connection limit on your web server based on available bandwidth and memory 

- uniform resource locator (URL): complete name of a web server

Secure Sockets layer and HTTPS
- Secure Sockets Layer(SSL): a protocol for transmitting private documents over the internet 

- Hypertext Transfer Protocol over SSL (HTTPS)

- Transport Layer Security (TLS)

Chapter 9: TCP/IP Applications pg 275 - 286

TCP
- Transmission control Protocol (TCP): enables connection-oriented communication in networks that use the TCP/IP protocol suite
- TCP three-way handshake
- most TCP/IP applications use TCP because connection-oriented sessions are designed to check for errors

DHCP
- Dynamic Host configuration Protocol
- can't assume another computer is ready on either side of the session
- uses port 67 for sending data the the DHCP server

NTP/SNTP
- Network Time Protocol (NTP)
- Simple Network Time Protocol (SNTP)
- synchronize the clocks of devices on the network

TFTP
- Trivial File Transfer Protocol (TFTP): enables you to transfer files from one machine to another
- has no data protection so it is not used for communication between computers across the internet

ICMP
- works at layer 3 to deliver connectionless packets
- handles disconnect messages

IGMP
- Internet Group Management Protocol (IGMP): enables routers to communicate with hosts to determine a "group" membership

Registered Ports
- ports numbers from 1024 to 49151 are called registered ports
- anyone can use these port numbers for their servers
- 0 to 1023: well-known ports
- 1024 to 4951: Registered ports
- 49152 to 65535: dynamic or private ports
- socket: connection data stored on a single computer
- socket pairs: the connection data stored on two computers
- connection: the whole interconnection

Chapter 8: Routing Pg 259 - End

IS-IS
- Intermediate system to Intermediate System (IS-IS): allows you to use a link state dynamic protocol without using OSPF
- uses the concept of areas and send-only updates to routing tables

EIGRP - The Lone Hybrid 
- Enhanced Interior Gateway Routing Protocol (EIGRP)
- replaced Interior Gateway Routing Protocol (IGRP)

Set Up of the WAN
- need to know the network IDs for each side of the router
- WAN invariably connects to an ISP

Set Up the LAN
- need to choose a netowrk ID
- need to assign the correct IP information to the LAN-side NIC

Configure A Dynamic Protocol
- dynamic protocols are tied to indiviudal NICs
- make sure the two NICs are configured to use the same dynamic routing protocol

Things To Remember:

1. A router is a peice of hardware that forwards packets based on IP address
2. A router can interconnect different layer 2 technologies
3. Port Address Translation enables you to share a single public IP address with many computers
4. distance vector routing protocols use hop count to determine the best route.
5. OSPF bases routes on speed and sends only route changes to minimize traffic.
6. Area 0 is known as the backbone.
7. Yost cable was invented to standardize the serial console interface.

Chapter 8: Routing Pg 252 - 258

BGP
- autonomous system (AS): one or more networks that are governed by a single dynamic routing protocol within that system
        -> do not use IP addresses
        -> they use a globally unique Autonomous System Number (ASN)
        -> originally 16-bit but are now 32-bit broken into two separate 16-bit numbers broken by a dot (.)
        -> AS's communicate using Exterior Gateway Protocol (EGP)
        -> networks with an AS communicate using Interior Gateway Protocols (IGP)
- Border Gateway Protocol (BGP - 4): connects all of the Autonomous Systems on the internet
        -> BGP routers are manually configured
        -> supports policies for limiting which and how other routers may access an ISP
       
Link State
- link state dynamic routing protocol 
        -> OSPF
        -> IS-IS

OSPF
- Open Shortest Path First (OSPF)
        -> used on internal networks
        -> converges faster and more efficiently than RIP 
        -> not often found on home routers
- link state advertisements (LSAs) are sent out by OSPF capable routers
        -> forwarded to every OSPF router in the network
- every router in the network is assigned an area ID 
- designated router (DR): relays information to all of the other routers in the area
- backdup desginated router (BDR): used in the event the DR is not available
        -> the DR and BDR compete to become the DR during the inital LSA packet exchange
- flooding when a new router initially starts and sends out a plethora of LSAs
- cost of an OSPF is based off of 100,000,000/bandwidth in bps
         -> the faster the bandwidth the lower the cost
- scales to large networks and is supported by nearly all routers
- OSPF corrects link failures and creates convergence almost immediately

Chapter 8: Routing Pg 236 - 252

Network Address Translation 
- Network Address Transnation (NAT): hide the IP addresses of computers on the LAN but still enable those computers to communicate with the broader network

The Setup
- requires a block of unique IP addresses
- basic NAT: router replaces the source IP with its outside interface address on outgoing packets
- dynamic NAT: many computers can share a pool of routable IP addresses

Port Address Translation
- Port Address Translation (PAT): uses port numbers to map traffic from specific machines in the network
- when the receiving system sends the packet back it reverses the IP addresses and ports

Port Forwarding
- Static NAT: maps a single routable IP address to a single machine
- port forwarding: can designate a specific local address for various network services
     -> computers outside the network can request a service using the public IP address and the port number for the service
     -> can be used to hide a service hosted inside a network by changing the default port number

Configuring NAT
- by default, routers are set to Gateway which means NAT is turned on

Dynamic Routing
- routers have static routes 
- most routers have the capability to update their routes dynamically 

Routing Metrics
- metric: a relative value that routers use when they have more than one route to get to another network
- a router will choose the route with the lowest value IP address
- there is no single rule to set the metric value in a routing table
- Maximum Transmission Unit:
        -> determines the largest frame a particular technology can handle

Distance Vector
- Distance Router:
        -> calculate the total cost to get to a particular network ID and compare that cost to the total cost of all the other routes
- each distance vector routing protocol has a maximum number of hops that a router will send its routing table to keep traffic down
- convergence (steady state):  the updating of the routing tables for all the routers has completed

RIPv1
- Routing Information Protocol(RIP): has a maximum hop count of 15
- variable-length subnet masking (VLSM): networks connected through the router using different subnet masks

RIPv2
- current version of RIP
- VLSM has been added and authentication is built into the protocol
- obsolete for small private WANs that consist of a few routers

Chapter 8: Routing pg 228 - 234

How Routers Work
- router: any piece of hardware that forwards packets based on their destination IP address
- routers work at the Network Layer of the OSI model and the Internet level of the TCP/IP model
- routers are dedicated boxes that contain at least two connections
- router reads the IP addresses of the packets to determine where to send the packets
- routers examine packets and send the packets to the proper destination

Routing Tables
- router inspects each packet's destination IP address and then sends the IP packet out the correct port

- routing table: tells the router exactly where to send the packets
       -> each row in a routing table defines a single route
       -> each column identifies a specific criteria
       -> Destination LAN IP: a defined network ID. Every directly connected network ID is listed here
       -> Subnet  Mask: needed to define a network ID
            - router uses the combination of the destination LAN IP and subnet mask to see if a packet matches the   route
       -> Gateway: the IP address for the next hop router (where the packet will go next)
       -> interface: indicates to the router which port to use
- router compares the destination LAN IP address on each packet toe very listing in the routing table before sending the packet out
- default route tells the router exactly what to do with every incoming packet
- multihomed computers: computers with more than one NIC
- to view routing table type the command: netstat -r

Chapter 7: TCP/IP Basics pg 216 - End

Dynamic IP Addressing 
- Dynamic Host Configuration Protocol (DCHP)
      -> automatically assigns an IP whenever a computer connects to the network

How DHCP Works( Uses ports 67 and 68)
- DHCP Client
- automatically sens out a special DHCP discover packet using the broadcast address
- discover message searches for DHCP servers
- one system on the LAN must be running DHCP server software
- designed to respond to DHCP discover requests
- DHCP server is configured to pass out IP addresses from an IP range (scope)
- DHCP servers can be set up to reserve addresses for specific machines (reservations)
- DHCP client sends out a DHCP request
- DHCP server then sends  DHCP acknowledge and lists the MAC address and IP information
- DHCP lease: the acceptance from the DHCP client of the DHCP server's data
         -> set for a fixed amount of time (5-8 days)
         -> near the end of the lease time, the DHCP client simply makes another DHCP Discover message
- DHCP server looks at the MAC address information and gives the DHCP client the same IP info

Living with DHCP
- biggest issue: a DHCP client tries to get a DHCP address and fails
        -> indicated by the operating system posting some form of error and the DHCP client has a strange  IP address
- Automatic Private IP Addressing (APIPA) : generates the "special" IP address
        -> all DHCP servers generate an APIPA address automatically if they do not recieve a response to  a DHCP Discover message
        -> DHCP client only generates the last two octets of an APIPA address
        -> APIPA cannot issue a default gateway which prevents internet access
        -> systems that use static IP addressing can never have DHCP problems

What to Remeber:

1. An IPv4 address consists of 32 bits.
2. The network ID is the first three octets when using the specified subnet
3. A subnet is all 1s followed by 0s

Chapter 7: TCP/IP Basics Pg 200 - 216

Class IDs
- Internet Assigned Numbers Authortiy (IANA)
       -> formed to track and distribute IP addresses to those who need them
- American Registry for Internet Numbers (ARIN)
       -> American region of the IANA

 - multicast licenses are used fro one-to-many communciation
- broadcast: every computer on the LAN hears the message
- unicast: one computer on the LAN hears the message
- multicast: multiple computers on the LAN hear the message

CIDR Subnetting
- subnetting: taking a single class of IP addresses and chopping it up into multiple smaller groups

Subnetting
- enables more efficient use of IP addresses
- allows separation of a network for security
- can extend the subnet mask by adding more ones
- never subnet without converting to binary
- has two goals
        -> efficiency and making multiple network IDs

Calculating Hosts
-  2^x - 2 = number of hosts
        -> x = number of zeros in the subnet mask

Calculating Subnets
- start with a beginning subnet mask and extend the subnet extension as far as you need
- 2^y where y = number of bits you add to the subnet mask

Manual Dotted Decimal to Binary Conversion
- best way to convert is with a calculator
- start with 128 and divide the number in half all the way to 1
- the place the binary numbers under the values from dividing 
- then add the decimal values that have a one underneath
-  128  64  32  16  8  4  2  1
   1      0    0     1   0  1  1  0
   128 + 16 + 4 + 2 = 150











  

 

Chapter 7: TCP/IP Basics Pg 184 - 198

IP Addresses
- most common IP addresses have a 32-bit value (IPv4)
- 32 binary digits broken into four groups of eight digits
- each 8bit value is converted into a decimal number between 0 and 255

Network IDs
- each computer on a LAN has a very similar IP address
- i.e. only the last number of the IP being unique to each system

Interconnecting
- must have a router to connect to other networks

Network+ Chapter 7: TCP/IP Basics pg 177 - 183

The TCP/IP Protocol Suite
- TCP/IP Model: Link, Internet, Transport, and Application layers

Internet Layer Protocols
- takes data chunks from the transport layer, adds an address, and creates the final IP packet
- IP then hands the IP packet to layer 2 for encapsulation into a frame
- ICMP: Internet Control Message Protocol
- full IP packet has 14 different fields

• Version (Ver): defines the type of IP address
• Header Length: total size of the IP portion of the packet in words
• Differentiated Services code Point (DSCP): contains data used by bandwidth sensitive applications 
• Time to Live (TTL): prevents an IP packet from indefinitely spinning through the internet 
• Protocol: Either TCP or UDP 

Transport Layer Protocols
- Transmission Control Protocol (TCP)
- User Datagram Protocol (UDP)

TCP
- 95% of all TCP/IP applications use TCP
- requires both the sending and the receiving machines to acknowledge the other's presence and readiness to send and receive data
- ACK/NACK or just ACK
- chops up data into segments, gives the segments a sequencing number, and verifies that all segments were received
- each application is designed a specific port number
- web servers use port 80 (HTTP)
- e-mail uses port 110 (POP3)
- TCP Headers

• Sequence Number: used to assemble/disassemble data
• ACK Number: tracks the readiness of the two communicating systems 
• Flags: give sending an receiving ends detailed information on state of connection
• Checksum: checks the TCP header for errors
• Source Port
• Destination Port 

 - UDP works best when transferring large amounts of data
 

Chapter 6: Installing a Physical Network pg 170 - End

Cable Testing
- need a midrange tester with TDR
- include the patch cables

Problems in the Telecommunications Room
- keep your diagnostics process documented and organized
- all racks should run off of an interruptible power supply
- all rooms should have temperature monitors
- all rooms should have environmental monitors

Things To Remember From Chapter:

1. Coax cable should not be used in structured cabling networks.
2. Bonding, or link aggregation, is the process of using multiple NICs as a single connection, thus increasing speed.
3. The CAT 5e rating requires four pairs of wires.
4. The patch panel organizes and protects the horizontal cabling in the telecommunications room. 
5. Patch cables are used to connect the hub to the patch panel and the PCs to the outlet boxes.
6. 10BaseT and 100BaseT use UTP cabling in a star topology. 10Base2 is an older, dying technology that doesn't use UTP in a star. Fiber-optic networking uses a star topology, but the name is a dead giveaway hat it doesn't use UTP. 
7. A tone generator and tone probe work together to enable you to pick a single cable out of a stack of cables.

The Beginnings of How the Internet Works

So I began the learning process first my replicating the demonstration in the presentation. The idea is to visualize and understand how one machine connects to another. I chose to see the connection between the machine here at the career center and python.org. I began by installing Scapy, and Graph Visualization Tools. I opened Scapy and use the traceroute command to see a list of all the IPs that my machine connects to in order to connect to python.org. I then used a command that would create an visual graph of all the hops the request took to reach python.org

Net+ Chapter 6: Installing a Physical Network pg 133 - 169

Patch Panels and Cables
- patch panel
        - a bow with a row of female connectors in front and permanent connections in the back
- 110 Block
        - UTP cables connect using a punch down tool
- 66 Block
        - used more commonly for telephone services but still common to find 66-blocks in a telecommunications room
- patch panels prevent horizontal cabling from being moved
- patch panels are also used to organize cables
- patch panels are available in:
        - UTP
        - STP
        - Fiber Optic
        - a mix of the three standards
- UTP patch panels come with ratings
- patch cables:
        - short (2-5 foot) UTP cables
        - stranded core

Demarc
- physical location of the connection and marks the dividing line of responsibility for the functioning of the network
- NIU:
          -> DSL or cable modem supplied by your ISP

Installing Structured Cabling 
- get a floor plan
- map the runs of the cables
- find an appropriate room for telecommunications
         - short distances from work areas
         - has a lot of power sockets
         - low humidity
         - temperature controls
         - not easily accessed

4th Quarter

1. During the 4th quarter, I will learn to properly set up and manage a school tool server for use in Senegal. In addition, I will complete a Python task that is essentially what this woman did.

2. During the 4th quarter, I will make a server for students in Senegal to use. I will also work together with Ben and John to complete a project on understanding how the internet works.

3. I hope to have tested and completed certification in Network+ by May 16th.

Chapter 6: Installing a Physical Network Pg 125 - 132

Understanding Structured Cabling:
- set of standards defined by TIA/EIA
- idea is to create a safe, reliable cabling infrastructure for all the devices that need interconnection

Structured Cable Network Components:
- requires a telecommunications room, horizontal cabling, work area

Horizontal Cabling
- cabling that goes horizontally from telecommunications to work room
- a CAT5e or better UTP
- should always be solid core

Solid Core vs. Stranded Core
- solid core UTP uses a single solid wire
- stranded core is a bundle of tiny wire strands

Number of Pairs:
- should use four-pair UTP
- larger bundled UTP in higher-end telephone setups

Choosing Your Horizontal Cabling:
- lower CAT level cable will work on most networks

Network+ Chapter 5: Modern Ethernet Page 120 - end

Backbones:
- Each flor has its own switch that connects to every node on the floor
- each of these switches has a separate high-speed connection to a main switch
- you need switches with separate, dedicated, high-speed ports
- add-on ports on the switches run straight to the backbone

Current Week

As of now, I am currently awaiting preparation for the server to be complete. John has missed several days this week for reasons unknown. In the meantime, I am continuing to study for Network+.

Chapter 5 Modern Ethernet Pg 115-119

Implementing Multiple Types of Gigabit Ethernet

10 Gigabit Ethernet
         - shows up in high-level LANs
         - fiber and copper standards
      
Fiber-based 1- GbE
         -  standardized by type of fiber used, wavelength of the lasers, and physical
layer signaling type
         - also define maximum signal distance
         - standards have names that start with "10GBase" and end in xy
         - x stands for type of fiber used
         - y code is always R ( for LAN-based signaling devices) and W for (SONET/WAN)
         - when x = S, S means short or 850nm over multimode fiber
              -> max fiber length being 300 Meters
         - when x - L, L means long or 1310 nm over single mode fiber
              -> max fiber length being 10 Kilometers
         - 10BaseLR connects LANS
         - 10BaseLW connects SONET
         - when x=E, E means Extra Long or 1550nm
                -> max fiber length of 40 Kilometers
      
The Other 10 Gigabit Ethernet Fiber Standards
         - 10BaseL4
               -> uses four lasers
               -> 1300nm wavelength
               -> legacy fiber
               -> 300 Meter max length
               -> multimode cable
          - 10BaseLRM
               -> long wavelength
               -> over legacy fiber
               -> max range of 220 meters
           - 10BaseZR
               -> not part of the IEEE standards
               -> uses 1550 nm wavelength
               -> max range of 80 Km

Copper-based 10GbE
           -running on twisted-pair cabling
           - called 10GBaseT
           - maximum cable length of only 55 meters with CAT6
           - maximum cable length of 100 meters with CAT6a
         

Chapter 5: Modern Ethernet Pg107-114

Must be able to:
         - Categorize standard media types and associated propertiees: media converters, distance limitations
         - Categorize standard connector types based on network media: fiber
         - compare and contrast different LAN technologies
         - Describe the varieties of 100-megabit ethernet
         - discuss coper and fiber based gigabit ethernet
         - compare the competing varieties of 10 gigabit ethernet

Upgrading from 10BaseT to 100 BaseT
         - First: Use CAT5 cable or better
         - Must replace all old 10BaseT NICs with 100BaseT NICs
       
 100BaseFX
         - 100 Megabit Ethernet fiber-optic cable
         - also known as 100BaseF
         - Speed: 100 Mbps
           Signal Type: Baseband
           Distance: 2Km between the hub and node
           Node Limit: 1024 per node
           Topology: Star-bus topology, physical star, logical bus
           Cable Type: multimode fiber-optic cabling with ST or SC connectors

Full-Duplex Ethernet
          - Can send and receive data at the same time
          - doesn't increase network speed, but doubles bandwidth
        

Gigabit Ethernet
          - 1000BaseT
          - 1000BaseX

1000BaseCX
         - uses twinaxial cable (or twinax)
         - 150-Ohm cables with length limit of 25 meters

1000BaseSX
         - multimode fiber-optic cables
         - max cable length of 220-500 meters
         - uses 850 nm wavelength LED
       
1000BaseLX
        - single-mode (laser) cables
        - max length of 5-70 Km

First XOs have arrived!

First step: Open the box...

much more difficult than it sounds as it was apparently found necessary to put multiple layers of varying types of tape on the box

Second step: Ensure they are in fact fully updated.

Now the important part: BUBBLE WRAP.

Sure enough they are fully updated and are running properly.

Next step: establish a server for the OLPCs to run on.

Chapter 4: Ethernet Basics pg 98-end

Crossover Cables:
- way in which hubs can connect to each other
- reverses the sending and receiving pairs on one end of the cale
- connects to a regular port on each hub
- never connect two hubs by their uplink ports with a straight-through cable

Bridges:
- acts like a repeater or hub to connect two ethernet segments
- filters and forwards traffic between those segments based on the MAC addresses of  the computers on those segments
- initially behaves exactly like a repeater
- however it monitors and records the network traffic
- mainly used in wireless networks

Switched Ethernet:

Trouble With Hubs:
- can only have one message on the wire at any time

Switches to the Rescue:
- create point-to-point connections between two computers
- copies the source MAC addresses and quickly creates a table of MAC addresses of each connected computer (Source Address Table)
- switch acts like a telephone operator
- can buffer incoming crames
- also known as a broadcast domain

Spanning Tree Protocol:
- switching loops: redundant connections in a network
- created to determine things like the distances between them

Troubleshooting Hubs and Switches:
- problems fall into three categories
           - Obvious physical damage
           - Dead ports
           - general flakiness

Network+ Chapter 4: Ethernet Basics Pg 93-97

10BaseT Limits and Specifications:
- cable connecting hub and computer cannot exceed 100 meters in length
- cannot connect more than 1024 computers
- Speed: 10 Mbps
  Signal Type: baseband
  Distance: 100 meters between the hub and the node
  Node Limit: No more than 1024 nodes per hub
  Topology: star-bus topology; physical star, logical bus
  Cable type: CAT 3 or better UTP cabling with RJ-45 connectors

10BaseFL Summary:
- Speed: 10Mbps
  Signal Type: Baseband
  Distance: 2000 Meters between the hub and the node
  Node Limit: No more than 1024 nodes per hub
  Topology: star-bus topology: physical star, logical bus
  Cable Type: Multimode fiber-optic cabling with ST or SC connectors

- Can use a media converter to interconnect different Ethernet types

Extending and Enhancing Ethernet Networks

Connecting Ethernet Segments 

You can connect hubs in two ways:
      - uplink port or a crossover cable
    

Uplink Ports 

- Enable you to connect two hubs using a straight-through cable
- you cannot use a single central hub and connect multiple hubs to that hub
- When connecting hubs:
         - only daisy-chain hubs
         - take time to figure out the uplink ports
        

Network+ Chapter 4: Ethernet Basics Page 85-92

Node (NIC): A member of a network or a point where one or more functional units interconnect transmission lines

            - Must have a unique identifying address
            - Identified using 48-bit binary addresses known as Mac Addresses

Mac Address: Unique 48-bit address assigned to each network card. IEEE assigns blocks of possible addresses to various NIC manufacturers to help ensure that each address is unique. The Data Link layer of the OSI seven-layer model uses MAC addresses for locating machines.

           - give each NIC a unique address
           - computers on the network listen to the wire to see if it contains their MAC address
           - if a machine sees it's address it opens the frame to process data

Sniffers: Diagnostic program that can order a NIC to run in a promiscuous mode.
           - Ethernet provides no protection against sniffers
Promiscuous Mode: A mode for a NIC in which the NIC processes all frames that it sees on the cable.

Frame: A defined series of binary data that is the basic container for container for a discrete amount of data moving across a network. Frames are created at Layer 2 of the OSI model.
           - computers can determine what type of data (IPv4 or IPv6)
           - type field does not tell you if the fram carries an email or web page

Data:
           - contains whatever payload the frame carries
         
Pad:
           - minimum Ethernet frame is 64 bytes (but not all has to be data)
           - if fewer than 64 bytes in size, the sending relay will automatically add extra data

Frame Check Sequence:
           - Ethernet's term for the cyclic redundancy check
           - Enables Ethernet nodes to recognize when bad things happen to good data
           - machines must be able to detect when data has been damaged
       
CSMA/CD:
           - Carrier sense multiple access/collision detection
           - determines which computer should use a shared cable
           - means that each node using the network examines the cable before sending data
           - network access method that maps to the IEEE 802.3 standard for Ethernet networks
           - multiple access means that all machines have equal access to the wire
           - collision domain is a group of nodes that have the capability of sending frames at the same time as each other
         

10BaseT:
            - created in 1990
            - 10 Mbps
            - signaling type: baseband
            - the cable only carries one type of signal
            - uses twisted pair cable
            - RJ-45 connector
            - enables devices to put voltage on the individual wires within the cable
            - designates some of these numbered wires for specific

Ubuntu Install on Student Laptop

Today I began installing Ubuntu on a students laptop.

The language was set to English(US).

The user-name was set by default by the system. The password was set as directed. The home directory was NOT encrypted.

Ubuntu is currently installing and will hopefully finish by the end of the class period.

The second laptop has no contact information on it and it is unknown exactly what should be done with it so nothing will be done to it until further information is discovered.

In addition today, the battery was changed out on the Dell tower for the elderly woman is now fully functional. It is ready for pickup.

Student Laptop Repair

The first set of projects began with replacing the LCD screen on a Dell laptop. The video that I watched made the project seem a lot easier than it actually is however, disconnecting the inverter is a lot less self explanatory than it may sound. The screen came out eventually and has been replaced.

I will now begin installing Ubuntu on the last two student laptops and create user accounts for them.

In addition, the woman's computer that was asked of us to repair has been repaired and it ready to return to her for use. 

Windows XP 2002 Continued

So I was able to get in contact with the customer. I discovered that her main problem was not being able to use her web browser due to excessive amounts of advertisements that would pop up on her screen. I diagnosed a virus and sure enough there was one. It has since been removed.

The next line of action is to ensure that the operating system is fully updated. Once this has been done, I will defragment her hard drive and run a disk cleaner to ensure that all unnecessary files are removed an no longer using her valuable usage space. In addition I will see what services run on her computer automatically and turn off any services that are unnecessary, also to ensure her computer runs a little bit faster.

Windows XP 2002 Repair

Yesterday we received a machine from a woman who needs our assistance fixing her computer. She has a Dell Dimension 8200 with Windows XP 2002. She has complained that it is just not running as efficiently as she thinks it should. The solution to this issue that we have come up with is to retrieve all of her data from the machine and then reinstall the operating system.

As I began trying to figure out how much data she had, I discovered that she has two hard drives. One of her hard drives is her main hard drive that she appears to be using. It has approximately 3.5 GB of data. Her other hard drive has only 65MB of data on it. The plan is to move all of her data to the alternate hard drive and then to give her a call and find out exactly what it is that she needs done.

As Windows XP is no longer supported by Microsoft (meaning they no longer update it) it is a security risk for her to have Windows XP. My concern with upgrading her operating system is that she may not adapt well to the change. From what I saw, all of her programs and services she currently has are supported by Windows XP; however the settings and setup of a newer version of Windows may not be the best option for her. I will call her and find out.

Third Quarter

During the third quarter I will be studying for my Network+ certification.

What I hope to produce during this quarter is in fact that certification.

Network+

I recently began studying for my Network+ certification exam. I have begun to read the book and ask questions of my peers to further understand the material.

My study plan for this book is to do a quick read through of the book itself. While I am doing this I will take notes, and make flashcards of the review questions, as well as any new vocabulary terms that the author has provided.

So far I have read Chapter 1 ( An overview of the book), Chapter 2 ( an overview of Network Models), Chapter 3 ( various types of network cables and network topologies), and Chapter 4 ( the basics of understanding Ethernet).

Old Projects Are Done Projects

Yesterday, I completed updating the final set of OLPCs. Apparently, I been using the wrong set of instructions.

Today, the laptops for HILT were completed.

The next project to be completed is unknown at this point in time but hopefully over the weekend, I can think of one.

OLPC Update Cont'd

Rather than begin with installing the missing drivers on the HILT Laptops, I began by updating the OLPCs. I went with the install option from a USB drive rather than an online update. I found that the firmware on both OLPCs was out of date causing an issue with updating the Sugar image (it will not install). To fix this issue, I needed to update it using a USB drive; however, I found that these particular OLPCs were secured. What secured basically means is that the operating system includes a developer key. As I do not have the developer key, I needed to find an option to update without it. This required holding down the '✓' (check) game pad key until prompted to release it. At this point, the OLPC begins to update the firmware.


After updating the firmware, I attempted to update the Sugar image. Once again, it showed me a "boot failed" error message. I traced my steps once again and discovered I have the sugar image developed for the XO 1.5 rather than the image for XO 1.

Old Projects Are New Projects

Since returning from our holiday break, we have receieved news that our project from before the break would be extended. We encountered an issue that several of the drivers (i.e. wireless driver) were not included in the Windows XP for Students image we had previously installed on the laptops for the HILT students. As a result, we are now in the process of manually installing the drivers on 40+ laptops.

In addition, we gained new partners in organizing the lab. From this new addition we discovered two more OLPCs that need to be updated and sent to Africa. These XOs will be flashed to avoid encountering any login issues.