Fath [ 幸福 ]

1. Explain the following wireless device and discuss how to properly choose each device.

Wireless Router

The purpose of a wireless router is to transfer data wirelessly from one location to another. The router is used to secure networks and to connect different devices to the Internet. Wireless routers connect to a LAN, or local area network, without the need of Ethernet cords.

Wireless AP

A wireless access point (WAP) is a hardware device or configured node on a local area network (LAN) that allows wireless capable devices and wired networks to connect through a wireless standard, including Wi-Fi or Bluetooth.

Wireless Print Servers

Wireless Print Server enables a single USB printer to be shared on a wireless network.  Wireless print servers are small devices (they look like mini routers) that have a USB port. All need to do to connect the printer to this wireless print server using a regular USB cable and the printer will then become available to all other computers in the wireless network.

Wireless Range Extender

A Wi-Fi range extender, sometimes called a range expander, is a type of wireless repeater used to expand the reach of a wireless LAN. The range extender connects wirelessly to the router or access point, picks up the signal and retransmits it. 

2. To create a good network the basic plan is

Decide what kind of WLAN is needed

Purchase the best equipment the budget allows for

Install the equipment

Test the installation

Identify where to effectively set-up access point?

The best place to set-up access point is as close as possible to the centre of the area that want to cover. Avoid surrounding it with metal objects, or Concrete or brick walls since it will distract the signals. 

How to secure wireless network?

Set up password for the router, and Encryption and limit access for the wireless network.

3. Identify the steps on troubleshoot network for the following problems

Workstation issues

Logging in problem - check and making sure the hardware and network infrastructure is all okay. Enter the username and password correctly. 

Ip Address problem -  each computer on a network is given a numerical address in the format xxx.xxx.xxx.xxx, make sure when enter at the command prompt the correct Ip Address. 

Network Cards-  check that all network cards are installed properly.

 Peer-to-Peer Networks -If cannot see shared resources on a peer-to-peer network, ensure the workgroup name is the same on all the PCs in the workgroup.

Access point issues

Check WAN and LAN connections - Check all wireless access point (AP) or wireless router ports to ensure that Ethernet cables are inserted tightly and link status LEDs are green at both ends.

Verify wireless adapter -  Ensure the client's Wi-Fi adapter used for network troubleshooting is enabled and ready to connect.

Verify AP and router settings - Use your wireless access point or router's administrative GUI to verify network settings for the wireless network service set identifier (SSID) to which your Wi-Fi client is trying to connect.

Verify TCP/IP settings

Verify network connection with Ping - Once the wireless client has a valid IP address, use ping to verify network connectivity.

Check wireless-specific issues - If the wireless client still cannot connect, get a valid IP address or ping theAP or router, then it's time to consider wireless-specific problems.

Look for a security mismatch - If a matched wireless client and AP or router can "hear" each other but still can't connect or exchange traffic, look for a security mismatch.

Ensure RADIUS is working - WPA and WPA2-Enterprise log the client into the network and deliver encryption keys using an 802.1X-capable RADIUS server.

Check 802.1X EAP and user login - If RADIUS is working but the client's access requests are rejected, look for an 802.1X Extensible Authentication Protocol (EAP) or user login problem.

Check intermittent network connectivity issues - Encounters intermittent network connectivity problems which lead to poor signal strength, RF interference, or disconnection caused by AP roaming.

Server/infrastructure issues.

Having an agreement with a network contractor with engineers trained in the operating system and hardware that are used.

It is essential to check that backups are actually running and then make sure the server can restore data properly.

Let the user get notified to save some files to local hard drives to work on while the server is unavailable or get crashed, and get maintenance.

If the users start complaining that the network is slow perhaps the server's hard drive is starting to fill up or it has become fragmented. Check the properties of the disk to see how much free space there are, and the server need to upgrade or add another disk.

Regular check the Uninterruptible Power Supply (UPS) in case it reach to a point where they can't hold a charge any longer and need replacing.

Reference

Reference. (2017). What is the purpose of a wireless router?. [online] Available at: https://www.reference.com/technology/purpose-wireless-router-1342bf64ebeb3b30 [Accessed 9 Jun. 2017].

Techopedia.com. (2017). What is a Wireless Access Point (WAP)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/13538/wireless-access-point-wap [Accessed 9 Jun. 2017].

What is Wi-Fi range extender (range expander)? - Definition from WhatIs.com. (2017). SearchMobileComputing. Retrieved 10 June 2017, from http://searchmobilecomputing.techtarget.com/definition/Wi-Fi-range-extender

How to Install a Wireless LAN. (2017). PCMAG. Retrieved 10 June 2017, from http://www.pcmag.com/article2/0,2817,1540976,00.asp

Securing Your Wireless Network | Consumer Information. (2017). Consumer.ftc.gov. Retrieved 10 June 2017, from https://www.consumer.ftc.gov/articles/0013-securing-your-wireless-network

Network Troubleshooting for Workstations. (2017). Techsoup.org. Retrieved 10 June 2017, from http://www.techsoup.org/support/articles-and-how-tos/network-troubleshooting-for-workstations

10 steps to troubleshoot wireless connection problems. (2017). SearchNetworking. Retrieved 10 June 2017, from http://searchnetworking.techtarget.com/tip/Wireless-network-troubleshooting-Connectivity

Research routing protocols and write a brief report that explains the difference between Interior Gateway Protocols and Exterior Gateway Protocols. Describe the protocols used.  

Routing protocols purpose to estimates the network date transfer by the use of software and routing algorithms, and the communication paths between network nodes along with the understanding of network topology.

 The difference between Interior Gateway Protocols and Exterior Gateway Protocols are.

Interior Gateway Protocol (IGP handles the  exchanging routing information between gateways within an Autonomous System while as the Exterior Gateway Protocol (EGP) handles routing information between two neighbor gateways house which is outside an Autonomous System.  

The protocols used for Interior Gateway protocols:

Distance Vector Protocols

Link State Protocols

Hybrid Protocols

The protocols used for Exterior Gateway protocols:

Border Gateway Protocol

List all the different types of specialist server you can think of or find via the Internet and books (e.g. mail server). Briefly describe each one.

Application Servers - An application server is a program that handles all application operations between users. It is a server program in a computer in a distributed network that provides the business logic for an application program.

Communication Server – It is a dedicated system that provides communication services for users on a network who need to transfer files or access information on systems or networks at remote locations over telecommunication links.

Domain Controllers/Directory Servers – It is a server that responds to security authentication requests within a Windows Server domain. 

Fax Servers – It is a system installed in a local area network (LAN) server that allows computer users who are attached to the LAN to send and receive fax messages. 

File Servers – It is a computer responsible for the central storage and management of data files so that other computers on the same network can access the files.

Print Servers – It is a software application, network device or computer that manages print requests and makes printer queue status information available to end users and network administrators.

Mail Servers – It is an application that receives incoming e-mail from local users (people within the same domain) and remote senders and forwards outgoing e-mail for delivery.

Web Servers – It is a program that uses HTTP (Hypertext Transfer Protocol) to serve the files that form Web pages to users, in response to their requests, which are forwarded by their computers' HTTP clients.

References

Webopedia.com. (2017). What is Application Server? Webopedia Definition. [online] Available at: http://www.webopedia.com/TERM/A/application_server.html [Accessed 23 May 2017].

Linktionary.com. (2017). Communication Server (Linktionary term) . [online] Available at: http://www.linktionary.com/c/comm_server.html [Accessed 23 May 2017].

Techopedia.com. (2017). What is a Domain Controller? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/4193/domain-controller [Accessed 23 May 2017].

WhatIs.com. (2017). What is fax server? - Definition from WhatIs.com. [online] Available at: http://whatis.techtarget.com/definition/fax-server [Accessed 23 May 2017].

SearchNetworking. (2017). What is file server? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/file-server [Accessed 23 May 2017].

WhatIs.com. (2017). What is print server? - Definition from WhatIs.com. [online] Available at: http://whatis.techtarget.com/definition/print-server [Accessed 23 May 2017].

SearchMicroservices. (2017). What is mail server (mail transfer/transport agent, MTA, mail router, Internet mailer)? - Definition from WhatIs.com. [online] Available at: http://searchmicroservices.techtarget.com/definition/mail-server-mail-transfer-transport-agent-MTA-mail-router-Internet-mailer [Accessed 23 May 2017].

Pair with @zahirahhm

Exercise 1

Research Category 5, 5e and 6 Ethernet cables and write a report giving a brief outline of each category including the frequencies used.

Category 5 cables:   Network cabling that consists of four twisted pair which is cooper wire that is terminated by an RJ-45 connector. Not only that CAT5 has maximum length of 100m without the help of bridge or network devices that can cause network problem. The maximum frequencies for the CAT5 is 100 MHz (megahertz)

Category 5e cables:  Cat-5e network cabling is used as a cabling infrastructure for 10BASE-T (Ethernet), full duplex 100BASE-TX (Fast Ethernet) and 1000BASE-T (Gigabit Ethernet, or GbE) networks. The Cat 5e used frequencies up to 100 MHz and can be used up to a maximum length of 100 meters and speed is 1000Mbps.

Category 6 Ethernet cables:  The cable uses thicker-gauge wires that can increase the shielding, which pair twists per inch in order to decrease the signal noise and interference. The maximum frequencies for 6 Ethernet cables are 250 MHz and the maximum data transfer rate is 55 meter.

 Exercise 2

1.       Examine the network in your college computer lab. State the type of network and physical topology used. Examine all network media and connectors in the lab. Write a brief report that gives the following detail:

a)  States the network type and physical topology (no diagram required)

The network type used in the college computer lab is Local Area Network (LAN) and the physical topology is the Extended Star Topology.

b)  Describes each connection (e.g. computers to face plate – do not report for each computer connected in this way) in the network including:

  Device at each end of the connection

 27 computers connected to the switches.

 1 printer connected to only one lecturer.

( Cable used (or wireless)

 Wireless LAN.

Ethernet.

(Cat 6 - identify by the label and the twisted length. )

 Connector used at each end

  RJ-45 connectors.

 c)  Describes connection to any external network. For example, connection to the telecommunications closet and vertical cabling and/or connection to the Internet.

 The physical topology is Extended Star Topology; the administration had two switches that connected through every lab. Each lab had switch that connected to the one of the administration’s switch. The switch in every lab then connected to all pc individually by its own face plate.

d)  If possible, get your teacher or network administrator to show you the data transfer rates on the network and include these in your report.

Identify the advantages of wireless network

Wireless Networking is relatively cheaper than wired Networks since they require no cables between the computers as well as lower long term costs due to less maintenance since there is less equipment. 

Wireless network equipment is plug-and-play, which helps reduce the total cost such as vendor installation and eliminates redundancy is case of a system crash. 

Wireless Networking is also very mobile and versatile; it is adaptable to most situations and requirements. 

Wireless networks can easily be set up and dissembled, which is perfect for many people who are on temporary worksites/homes or leased space. 

Wireless networks provide networking in places where regular wire cannot reach such as the backyard in a home situation. 

Access points can be used to boost the wireless signal range if required. Since portable workstations such as laptops have become popular, wireless networks can provide quick and easy access to the internet and workspaces for students and teachers in universities etc. 

It is also extremely easy to add other components onto this type of network such as easy installation of VoIP and printers etc without the need to configure ones computer. 

List all of the wireless devices in your home and college. Briefly explain the purpose of the each device

Phone - To be able to make and receive telephone calls.

Laptop -  Designed for portability and enable people to work on their projects from virtually anywhere.

Printer -  Device that accepts text and graphic output from a computer and transfers the information to paper, usually to standard size sheets of paper.

PC -  Perform calculations, store information, retrieve data and process information.

Research the IEEE 802.11g and 802.11n standards. Explain the key points of each standard including the data rates & make comparison between the two standards.

The 802.11g specification is a standard for wireless local area networks (WLANs) that offers transmission over relatively short distances at up to 54 megabits per second (Mbps), compared with the 11 Mbps theoretical maximum with the earlier 802.11b standard.

802.11g attempts to combine the best of both 802.11a and 802.11b.

802.11g supports bandwidth up to 54 Mbps, and it uses the 2.4 GHz frequency for greater range. 802.11g is backward compatible with 802.11b, meaning that 802.11g access points will work with 802.11b wireless network adapters and vice versa.

Pros of 802.11g - Fast maximum speed; signal range is good and not easily obstructed.

Cons of 802.11g - Costs more than 802.11b; appliances may interfere on the unregulated signal frequency.

802.11n is a specification for wireless LAN (WLAN) communications. 802.11n, an addition to the 802.11 family of standards, will increase wireless local area network(WLAN) speed, improve reliability and extend the range of wireless transmissions.

802.11n (also sometimes known as "Wireless N") was designed to improve on 802.11g in the amount of bandwidth supported by utilizing multiple wireless signals and antennas (called MIMO technology) instead of one.802.11n also offers somewhat better range over earlier Wi-Fi standards due to its increased signal intensity, and it is backward-compatible with 802.11b/g gear.

Pros of 802.11n - Fastest maximum speed and best signal range; more resistant to signal interference from outside sources.

Cons of 802.11n - Standard is not yet finalized; costs more than 802.11g; the use of multiple signals may greatly interfere with nearby 802.11b/g based networks.

Explain the different wireless network security risks and give the possible solution in order to avoid these risks. 

1. Rogue Access Points -  A method that is often used by attackers targeting wireless LANS is to setup a rogue access point that is within the range of the existing wireless. These are solutions to prevent the risk:

Build a policy prohibiting introducing network equipment into the network which is not owned by or approved by the company IT department.

Enforce port security so that unknown mac addresses cannot connect to your network.

Set up a separate wireless network. These access points should be secured with PEAP.

Regular security scans using tools like netstumbler to detect and track rogue access points in your network.

Perform IPsec over your network so that in case someone does set up a rogue AP, the exposed "waves" will not be plain readable in case of someone sniffing the wireless network.

2. Denial of Service -  This can be done by simply sending a large amount of traffic at a specific target.These are solutions to prevent the risk: 

Easy installation on Apache and IIS server.

Strong security against known and emerging hacking attacks

Best-of-breed predefined security rules for instant protection

Interface and API for managing multiple servers with ease

Requires no additional hardware, and easily scales with your business

3. Passive Capturing - Passive capturing is performed by simply getting within range of a target wireless LAN and then listening and capturing data.To avoid this is by implement high security standards using complex parameters.

List at least FOUR (4) wireless networking protocols and explain each protocols. 

1. 3G & 4G 

3G was the first “high speed” cellular network, and is a name that refers to a number of technologies that meet IMT-2000 standards. 4G is the generation of cellular standards that followed 3G, and is what most people use today for mobile cellular data. It needs a constant power source or must be able to be recharged regularly.

2. NFC 

Near Field Communication (NFC) is a short-range wireless connectivity standard (Ecma-340, ISO/IEC 18092) that uses magnetic field induction to enable communication between devices when they're touched together, or brought within a few centimeters of each other.

3.  LoRaWAN

A media access control (MAC) protocol for wide area networks. It is designed to allow low-powered devices to communicate with Internet-connected applications over long range wireless connections. LoRaWAN can be mapped to the second and third layer of the OSI model.

4. EnOcean

EnOcean is a protocol designed specifically for energy harvesting applications that are extremely low power. Thus, its applications are centered around building automation, smart homes, and wireless lighting control.

.

Reference

UKEssays. (2015). Wireless Network Advantages and Disadvantages. [online] Available at: https://www.ukessays.com/essays/information-technology/wireless-network.php [Accessed 3 May 2017]. 

SearchMobileComputing. (2017). What is 802.11g? - Definition from WhatIs.com. [online] Available at: http://searchmobilecomputing.techtarget.com/definition/80211g [Accessed 3 May 2017]. 

SearchMobileComputing. (2017). What is 802.11n? - Definition from WhatIs.com. [online] Available at: http://searchmobilecomputing.techtarget.com/definition/80211n [Accessed 3 May 2017]. 

Lifewire. (2017). What's 802.11? What These Wireless Standards Mean. [online] Available at: https://www.lifewire.com/wireless-standards-802-11a-802-11b-g-n-and-802-11ac-816553 [Accessed 3 May 2017]. 

M.eet.com. (2017). [online] Available at: http://m.eet.com/media/1056129/11n-fig1.jpg [Accessed 3 May 2017].

network?, H. (2017). How do you prevent rogue wireless access points on a network?. Networkengineering.stackexchange.com. Retrieved 5 May 2017, from https://networkengineering.stackexchange.com/questions/123/how-do-you-prevent-rogue-wireless-access-points-on-a-network  

Prevent Denial of Service (DoS) Attacks. (2017). Applicure.com. Retrieved 5 May 2017, from http://www.applicure.com/solutions/prevent-denial-of-service-attacks

Wireless Security Considerations: Common Security Threats to Wireless Networks. (2017). Pluralsight.com. Retrieved 5 May 2017, from https://www.pluralsight.com/blog/it-ops/wireless-lan-security-threats

What is Near Field Communication (NFC)? - Definition from WhatIs.com. (2017). SearchMobileComputing. Retrieved 5 May 2017, from http://searchmobilecomputing.techtarget.com/definition/Near-Field-Communication

Home - The Things Network Wiki. (2017). Thethingsnetwork.org. Retrieved 5 May 2017, from https://www.thethingsnetwork.org/wiki/LoRaWAN/Home

Topic Title: IP SUBNETTING 

IP Address 

 - It is a logical numerical address that uniquely identified a devices that is part of a TCP/IP  on IP network such as a single computer.  - Made up of 32 bits.  - Can be divisible into a network portion and host portion with the help of as subnet mask

- two IP addressing operates: OSI model (network layer) & TCP/IP (internet layer)  - BINARY OCTETS CONVERT TO DECIMAL (below)  -> The octets are broken down to provide an addressing scheme that can accommodate large and small networks.

IP Address Classes 

Class A: 

The first octet is the network portion

Major network address of 1.0.0.0 − 127.255.255.255

Octets 2, 3, and 4 (the next 24 bits) are for the networkmanager to divide into subnets and hosts as he/she sees fit

Used for networks that have more than 65,536 hosts

Class B: 

The first two octets are the network portion

Major network address of 128.0.0.0 − 191.255.255.255

 Octets 3 and 4 (16 bits) are for local subnets and hosts

Used for networks that have between 256 and 65,534 hosts.

Class C: 

The first three octets are the network portion

Major network address of 192.0.0.0 − 233.255.255.255

Octet 4 (8 bits) is for local subnets and hosts − perfect for networks with less than 254 hosts.

Network Masks

Helps to know which portion of the address identifies the network and which portion of the  address identifies the host

Class A, B and C = default masks = natural masks. 

The mask helps you identify the network and node parts of the address, convert the address and mask to binary numbers.

Identifying the network ID and host ID is easier when have the address and the mask represented in binary.  

bits set to 1 represent the network ID.

bits set to 0 represent the host ID.

Subnetworks 

known as subnets

A logically visible subdivision of an IP network

The practice of dividing a network into two or more networks is called subnetting

A subnetwork is a network which covers only part of a project and is linked in relationships with other subnetworks in the same project.

Used the subnetworks to refine and detail the networks as planning progresses. The system treats subnetworks and networks the same, that is, can plan dates, capacities, costs, materials and production resource/tools also with a subnetwork.

Subnetting

It allows you to create multiple logical networks that exist within a single Class A, B, or C network

If you do not subnet, you are only able to use one network from your Class A, B, or C network

Each data link on a network must have a unique network ID

With every node on that link being a member of the same network

If you break a major network (Class A, B, or C) into smaller subnetworks, it allows you to create a network of interconnecting subnetworks

Each data link on this network would then have a unique network/subnetwork ID.

In order to subnet a network, extend the natural mask using some of the bits from the host ID portion of the address to create a subnetwork ID.

Router, subnetworks, IP address. 

Each of the router is attached to four subnetworks

One subnetwork is common to both routers

Each router has an IP address for each subnetwork to which it is attached

Each subnetwork could support up to 30 host addresses

The more host bits you use for a subnet mask, the more subnets you have available.

The more subnets available, the less host addresses available per subnet

Variable-Length Subnet Masking (VLSM)

VLSM is a process of dividing an IP network into the subnets of different sizes without wasting IP addresses. When we perform Subnetting, all subnets have the same number of hosts, this is known as FLSM (Fixed length subnet mask). In FLSM all subnets use same subnet mask, this lead to inefficiencies.

Variable Length Subnet Mask (VLSM) extends classic Subnetting. VLSM is a process of breaking down subnets into the smaller subnets, according to the need of individual networks.

Steps for VLSM Subnetting

Find the largest segment. Segment which need largest number of hosts address. 

Do Subnetting to fulfill the requirement of largest segment.

Assign the appropriate subnet mask for the largest segment. 

For second largest segments, take one of these newly created subnets and apply a different, more appropriate, subnet mask to it. 

Assign the appropriate subnet mask for the second largest segment. 

Repeat this process until the last network.

1. Give the difference between a MAC and an IP address.

Media Access Control Address (MAC)  - It’s an identifier for the specific hardware and known as physical address or hardware address.  It had its own unique address and be easily identified the network that may use your device’s address.

Internet Protocol (IP) - It’s an identifier that’s labeled numerically to a particular device on the network that uses TCP/IP to interact, and the address that uses the network can not be identified outside the network.

2. Explain each section of the IP Address Header

VERs -  A 4-bit field that identifies the IP version being used. The current version is 4, and this version is referred to as IPv4.

HLEN - A 4-bit field containing the length of the IP header in 32-bit increments. The minimum length of an IP header is 20 bytes, or five 32-bit increments. The maximum length of an IP header is 24 bytes, or six 32-bit increments. Therefore, the header length field should contain either 5 or 6.

SERVICE TYPE -  The 8-bit ToS uses 3 bits for IP Precedence, 4 bits for ToS with the last bit not being used. The 4-bit ToS field, although defined, has never been used.

TOTAL LENGTH -  Specifies the length of the IP packet that includes the IP header and the user data. The length field is 2 bytes, so the maximum size of an IP packet is 216 – 1 or 65,535 bytes.

INDETIFICATION, DF, MF and FRAGMENT OFFSET -  As an IP packet moves through the Internet, it might need to cross a route that cannot handle the size of the packet. The packet will be divided, or fragmented, into smaller packets and reassembled later. These fields are used to fragment and reassemble packets.

TIME TO LIVE -  It is possible for an IP packet to roam aimlessly around the Internet. If there is a routing problem or a routing loop, then you don't want packets to be forwarded forever. A routing loop is when a packet is continually routed through the same routers over and over. The TTL field is initially set to a number and decremented by every router that is passed through. When TTL reaches 0 the packet is discarded.

PROTOCOL -  In the layered protocol model, the layer that determines which application the data is from or which application the data is for is indicated using the Protocol field. This field does not identify the application, but identifies a protocol that sits above the IP layer that is used for application identification.

HEADER CHECKSUM -  A value calculated based on the contents of the IP header. Used to determine if any errors have been introduced during transmission.

SOURCE ADDRESS -  32-bit IP address of the sender.

DESTINATION ADDRESS -  32-bit IP address of the intended recipient.

IP OPTIONS and DATA  -  A field that varies in length from 0 to a multiple of 32-bits. If the option values are not a multiple of 32-bits, 0s are added or padded to ensure this field contains a multiple of 32 bits.

List the different IP Address classes within its corresponding details

Class A, 1.0.0.1 to 126.255.255.254

Class B, 128.1.0.1 to 191.255.255.254

Class C, 192.0.1.1 to 223.255.254.254

Class D, 224.0.0.0 to 239.255.255.255

Class E, 240.0.0.0 to 254.255.255.254

3. Identify the IP version 4 public addresses and IP version 4 private addresses

IP version 4 public addresses:

Private Class A range 10.0.0.0 - 10.255.255.255

Private Class B range 172.16.0.0-172.31.255.255

Private Class C range 192.168.0.0-192.168.255.255

Loopback Addresses 127.0.0.0-127.255.255.255

IP version 4 private addresses:

1.0.0.0 - 9.255.255.255

11.x.x.x - 126.255.255.255

129.0.0.0 - 169.253.255.255

169.255.0.0 - 172.15.255.255

172.32.0.0 - 191.0.1.255

192.0.3.0 - 192.88.98.255

192.88.100.0 - 192.167.255.255

192.169.0.0 - 198.17.255.255

198.20.0.0 - 223.255.255.255

4. Identify the difference between IP version 4 and IP version 6 addresses

IPv4 addresses are 32 bit length. IPv6 addresses are 128 bit length.

IPv4 addresses are binary numbers represented in decimals. IPv6 addresses are binary numbers represented in hexadecimals.

No packet flow identification. Packet flow identification is available within the IPv6 header using the Flow Label field.

Checksum field is available in IPv4 header No checksum field in IPv6 header.

Options fields are available in IPv4 header. No option fields, but IPv6 Extension headers are available.

Address Resolution Protocol (ARP) is available to map IPv4 addresses to MAC addresses. Address Resolution Protocol (ARP) is replaced with a function of Neighbor Discovery Protocol (NDP).

Internet Group Management Protocol (IGMP) is used to manage multicast group membership. IGMP is replaced with Multicast Listener Discovery (MLD) messages.

Broadcast messages are available. Broadcast messages are not available. Instead a link-local scope "All nodes" multicast IPv6 address (FF02::1) is used for broadcast similar functionality.

Manual configuration (Static) of IPv4 addresses or DHCP (Dynamic configuration) is required to configure IPv4 addresses. Auto-configuration of addresses is available in IPv6.

5. Give the differences between TCP and UCP

TCP stands for “Transmission Control Protocol” while UDP stands for “User datagram Protocol”.

TCP is connection oriented protocol while UDP is connectionless protocol.

TCP is more reliable than UDP.

UDP is more faster for data sending than TCP.

UDP makes error checking but no reporting but TCP makes checks for errors and reporting.

TCP gives guarantee that the order of data at receiving end is same as on sending end while UDP has no such guarantee.

Header size of TCP is 20 bytes while that of UDP is 8 bytes.

TCP is heavy weight as it needs three packets to setup a connection while UDP is light weight.

TCP has acknowledgement segments but UDP has no acknowledgement.

TCP is used for application that require high reliability but less time critical whereas UDP is used for application that are time sensitive but require less reliability.

6. Explain what is a subnet and subnet addressing.

A subnet is an identifiably separate part of an organization's network. A portion of a network that shares a common address component. On TCP/IP networks, subnets are defined as all devices whose IP addresses have the same prefix.

Subnet addressing known as a subnet mask because it is used to identify network address of an IP address by performing a bitwise AND operation on the netmask. A Subnet mask is a 32-bit number that masks an IP address, and divides the IP address into network address and host address.

Explain VLSM and identify its purpose.

A Variable Length Subnet Mask (VLSM) is a numerical masking sequence, or IP address subset, based on overall network requirements. A VLSM allows a network administrator to use long masks for networks with few hosts and short masks for networks with multiple hosts. A VLSM is used with a VLSM router and must have routing protocol support.

Reference

Theydiffer.com. (2017). Mac Address vs IP Address - What's the difference?. [online] Available at: http://theydiffer.com/difference-between-a-mac-address-and-an-ip-address/ [Accessed 20 Apr. 2017].

Parkhurst, W. (2017). IP Header Format > Internet Addressing and Routing First Step. [online] Ciscopress.com. Available at: http://www.ciscopress.com/articles/article.asp?p=348253&seqNum=4 [Accessed 20 Apr. 2017].

Computerhope.com. (2017). What is IP (Internet Protocol)?. [online] Available at: http://www.computerhope.com/jargon/i/ip.htm [Accessed 23 Apr. 2017].

Inetdaemon.com. (2017). Private IPv4 Addresses - InetDaemon's IT Tutorials. [online] Available at: http://www.inetdaemon.com/tutorials/internet/ip/addresses/private_addresses.shtml [Accessed 23 Apr. 2017].

Inetdaemon.com. (2017). Public IP Addresses - InetDaemon's IT Tutorials. [online] Available at: http://www.inetdaemon.com/tutorials/internet/ip/addresses/public_addresses.shtml [Accessed 23 Apr. 2017].

Omnisecu.com. (2017). Differences Between IPv4 and IPv6. [online] Available at: http://www.omnisecu.com/tcpip/ipv6/differences-between-ipv4-and-ipv6.php [Accessed 23 Apr. 2017].

Difference Between. (2015). Difference between TCP and UDP. [online] Available at: http://www.differencebtw.com/difference-between-tcp-and-udp/ [Accessed 23 Apr. 2017].

SearchNetworking. (2017). What is subnet (subnetwork)? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/subnet [Accessed 23 Apr. 2017].

Iplocation.net. (2017). What is a Subnet Mask?. [online] Available at: https://www.iplocation.net/subnet-mask [Accessed 23 Apr. 2017].

Question 

Research all of the protocols mentioned in Topic 2, Lecture 2. Give a brief overview of each one. Identify in which layer of the OSI Model they belong.

Answers

Physical Layer protocols .

DataLink Layer protocols.

Ethernet -  Responsible on how networked devices can format data for transmission to other network devices on the same network segment.

Token Ring - Local area network (LAN) topology where nodes/stations are arranged in a ring topology. 

FDDI - Fiber Distributed Data Interface. Responsible for geographically large-scaled organizations that support thousands of end user. 

IEEE 802.11 -  Set of standards that define communication for wireless LANs (wireless local area networks, or WLANs).

ATM - Asynchronous Transfer Mode. A switching technique used by telecommunication networks that uses asynchronous time-division multiplexing to encode data into small, fixed-sized cells.

PPP - Point-to-Point Protocol. Provide a standard way to transport multi protocol data over point-to-point links.

HDLC - High-level Data Link Control. Transmitting data between network points.

Network Layer Protocols 

IP- Internet Protocols. Method of data is sent from one computer to another on the Internet.

OSPF- Open Shortest Path First. Used to find the best path for packets as they pass through a set of connected networks.

BGP - Border Gateway Protocol. Manages how packets are routed across the internet through the exchange of routing and reachability information between edge routers.

NetBEUI -  NetBIOS Extended User Interface.  Provides network/network layer support while optimizing small to medium-sized operating systems (OS)

DDP - Distributed Data Protocol. Uses to communicate between the client and the server.

Transport Layer protocol

TCP - Transmission Control Protocol. Establish and maintain a network conversation via which application programs can exchange data.

UDP - User Datagram Protocol.  Used to send short messages called datagrams. 

NetBEUI - NetBIOS Extended User Interface. Lets computers communicate within a local area network.

SPX - Sequenced Packet Exchange.  Handles the connections between systems. 

ATP- Autonomous transport protocol.  Maintain a reliable transport connection between two endpoints. 

Session Layer Protocols

ASP - Application service provider. Provides individual users – or an entire enterprise – with software applications over a network,

NetBIOS - Network Basic Input/Output System. Allows applications on different computers to communicate within a local area network (LAN).

Presentation Layer Protocols

AFP - Apple Filing Protocol.  Allows users to access outside system files.

SMB - Server Message Block.  Allows systems within the same network to share files.

NCP - Network Control Program. Allowed users to access and use computers and devices at remote locations and to transmit files between computers.

SSL - Secure Sockets Layer.  Establishing an encrypted link between a web server and a browser.

MIME -  Multi-Purpose Internet Mail Extensions. Exchange different kinds of data files on the Internet. 

Application Layer Protocols 

DHCP - Dynamic Host Configuration Protocol. Communications protocol that network administrators use to centrally manage and automate the network configuration of devices attaching to an Internet Protocol (IP) network.

HTTP :  HyperText Transfer Protocol. Protocol used read the html language.

FTP :  File Transfer Protocol.  Sharing files to another.

POP3 :  Post Office Protocol 3.  POP 3 responsible of receiving the mail.

SMTP : Simple Mail Transfer Protocol. SMTP responsible for sending the email.

IMAP : Internet Message Access Protocol. It is a protocol for accessing email on a remote server from a local client. It is a method of accessing e-mail messages on a server without having to download them to your local hard drive.

   ( SMTP -> POP3 -> IMAP )

References

SearchNetworking. (2017). What is Ethernet? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/Ethernet [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is a Token Ring Network? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/26095/token-ring-network [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is a Fiber Distributed Data Interface (FDDI)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/5588/fiber-distributed-data-interface-fddi [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is IEEE 802.11? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/24967/ieee-80211 [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is Asynchronous Transfer Mode (ATM)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/5339/asynchronous-transfer-mode-atm [Accessed 18 Apr. 2017].

SearchNetworking. (2017). What is PPP (Point-to-Point Protocol)? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/PPP [Accessed 17 Apr. 2017].

SearchNetworking. (2017). What is HDLC (High-level Data Link Control)? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/HDLC [Accessed 17 Apr. 2017].    

SearchUnifiedCommunications. (2017). What is Internet Protocol? - Definition from WhatIs.com. [online] Available at: http://searchunifiedcommunications.techtarget.com/definition/Internet-Protocol [Accessed 17 Apr. 2017]. 

SearchEnterpriseWAN. (2017). What is OSPF (Open Shortest Path First)? - Definition from WhatIs.com. [online] Available at: http://searchenterprisewan.techtarget.com/definition/OSPF [Accessed 17 Apr. 2017]. 

SearchTelecom. (2017). What is BGP (Border Gateway Protocol)? - Definition from WhatIs.com. [online] Available at: http://searchtelecom.techtarget.com/definition/BGP [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is NetBIOS Extended User Interface (NetBEUI)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/8529/netbios-extended-user-interface-netbeui [Accessed 17 Apr. 2017]. 

SearchWindowsServer. (2017). What is NetBEUI (NetBIOS Extended User Interface)? - Definition from WhatIs.com. [online] Available at: http://searchwindowsserver.techtarget.com/definition/NetBEUI-NetBIOS-Extended-User-Interface [Accessed 17 Apr. 2017]. 

SearchNetworking. (2017). What is HDLC (High-level Data Link Control)? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/HDLC [Accessed 17 Apr. 2017]. 

SearchNetworking. (2017). What is TCP (Transmission Control Protocol)? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/TCP [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is User Datagram Protocol (UDP)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/13460/user-datagram-protocol-udp [Accessed 17 Apr. 2017]. 

Techterms.com. (2017). SPX (Sequenced Packet Exchange) Definition. [online] Available at: https://techterms.com/definition/spx [Accessed 17 Apr. 2017]. 

Ieeexplore.ieee.org. (2017). ATP: autonomous transport protocol - IEEE Xplore Document. [online] Available at: http://ieeexplore.ieee.org/document/1562312/ [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is an Application Service Provider (ASP)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/2476/application-service-provider-asp [Accessed 17 Apr. 2017]. 

SearchNetworking. (2017). What is NetBIOS (Network Basic Input/Output System)? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/NetBIOS [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is AppleTalk Filing Protocol (AFP)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/25674/appletalk-filing-protocol-afp [Accessed 17 Apr. 2017]. 

Techterms.com. (2017). SMB (Server Message Block) Definition. [online] Available at: https://techterms.com/definition/smb [Accessed 17 Apr. 2017]. 

Techopedia.com. (2017). What is Network Control Protocol (NCP)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/27856/network-control-protocol-ncp [Accessed 17 Apr. 2017]. 

info.ssl.com (2017).  Q10241 - FAQ: What is SSL? . [online] Available at:  http://info.ssl.com/article.aspx?id=10241 [Accessed 17 Apr. 2017].

SearchMicroservices. (2017). What is MIME (Multi-Purpose Internet Mail Extensions)? - Definition from WhatIs.com. [online] Available at: http://searchmicroservices.techtarget.com/definition/MIME-Multi-Purpose-Internet-Mail-Extensions [Accessed 17 Apr. 2017]. 

Technet.microsoft.com. (2017). What Is DHCP?: Dynamic Host Configuration Protocol (DHCP). [online] Available at: https://technet.microsoft.com/en-us/library/cc781008(v=ws.10).aspx [Accessed 17 Apr. 2017]. 

SearchEnterpriseWAN. (2017). What is File Transfer Protocol (FTP)? - Definition from WhatIs.com. [online] Available at: http://searchenterprisewan.techtarget.com/definition/File-Transfer-Protocol [Accessed 17 Apr. 2017]. 

 Question 1;

IEEE 802 : Institute of Electrical and Electronic Engineering. 

Research the IEEE  802 working groups. List each group with a brief description and state whether it is active or not.

802.1 - Interconnection (Bridging). IEEE 802.1 handles the network management and security of LAN, MAN and WAN standardized by IEEE 802. IEEE 802.1 is active.  

802.2 - Logical Link. IEEE 802.2 concerned with issues of multiplexing, flow control, and detection and retransmission of dropped frames. IEEE 802.2 is inactive. ( serial connection DCE  and DTE ) 

802.3 - Ethernet.  IEEE 802.3 specifies the physical and networking characteristics of an Ethernet network, like how physical connections between nodes (routers/switches/hubs) are made through various wired media like copper coaxial or fiber cable.  IEEE 802.3 is active.

802.4 - Token Bus. IEEE 802.4 for a local area network (LAN) token passing protocol based on a physical bus topology, which is used in the MAP factory automation protocol.  IEEE 802.4 is disband because of lack of interest. .

802.5 - Token Ring. IEEE 802.5 for  a token ring local area network access method, which is widely implemented in Token Ring. IEEE 802.5 is inactive.

802.6 -  Metropolitan Area Networks (DQDB).  IEEE 802.6 is a standard for Metropolitan Area Networks (MANs).  IEEE 802.6 is disband.

802.7 - Broadband LAN. IEEE 802.7 is a standard for a broadband local area network (LAN) using coaxial cable. This standard was developed for cable Internet companies.  IEEE 802.7 is disband.

802.8 - Fiber Optic TAG. IEEE 802.8 was a working group concerned with designing a fiber optic LAN. This protocol was never adopted and IEEE 802.8 is disband.

802.9 - Isochronous LAN.  IEEE 802.9 is design for the integration of voice and data networks, both within the LAN domain and interfacing to publicly and privately administered networks running protocols. IEEE 802.9 is withdraw.

802.10 - Security.  IEEE 802.10 is standard for Interoperable LAN/MAN Security (SILS). IEEE 802.10 is withdraw in 2004.

802.11 - Wireless LAN. IEEE 802.11 is the protocol commonly used for wireless networking. Variants include 802.8g ("wireless-g") and 802.8n ("wireless-n"). IEEE 802.11 is active. 

802.12 - Demand Priority. IEEE 802.12 standard for 100+ Mbps LANs using demand priority access. The focus was on 100VG-AnyLAN, a standard that is considered obsolete. IEEE 802.12 is inactive.

802.14 - Cable Modem.  IEEE 802.14 for Broadband Cable Access Method and Physical Layer Specification in Local and Metropolitan Networks.  IEEE 802.14 is withdraw.

802.15 - Wireless Personal Aread Network (PAN).  IEEE 802.15 is a protocol defined for personal area network (usually meaning a network between only two devices). 802.15.1 is commonly known as Bluetooth. IEEE 802.15 is active.

802.16 - Broadband Wireless.  IEEE 802.16 is a group of broadband wireless communications standards for metropolitan area networks (MANs) developed by a working group of the Institute of Electrical and Electronics Engineers (IEEE). IEEE 802.16 is active.

802.17 - Resilient Packet Ring. IEEE 802.17 is part of the IEEE's local area network (LAN) and metropolitan area network (MAN) Committee and with the intention of creating a new Media Access Control layer for fiber optic rings.  IEEE 802.17 is active.

802.18 - Radio Regulatory Technical Advisory Group. IEEE 802.18 doesn’t create wireless standards but helps to create the correct regulatory environment. IEEE 802.18 is active. 

802.19 - Wireless Coexistence Technical Advisory Group. IEEE 802.19 specifies radio technology independent methods for network-based coexistence among dissimilar or independently operated networks of unlicensed devices and dissimilar unlicensed devices. IEEE 802.19 is active.

802.20 - Mobile Broadband Wireless. IEEE 802.20 provides an introduction to the activities with regard to this standard, including purpose and scope that the specification defines. IEEE 802.20 is active.

802.21 - Media Independent Handoff.    IEEE 802.21 enables the optimization of services including handover service when performed between heterogeneous IEEE 802 networks. It also facilitates these services when networking between IEEE 802 networks and Cellular networks. IEEE 802.21 is active.

802.22 - Wireless Regional Area Networks.  IEEE 802.22 standard for fixed wireless broadband access in rural and remote areas.  IEEE 802.22 is active.

Question 2;

Research the following standards and for each standard, briefly describe the devices to which it relates.

a) RS232 

RS-232 is a standard communication protocol for linking computer and its peripheral devices to allow serial data exchange. In simple terms RS232 defines the voltage for the path used for data exchange between the devices. It specifies common voltage and signal level, common pin wire configuration and minimum, amount of control signals.

An devices that relates are the interface between Data terminal equipment ( DTE )and Data communication equipment ( DCE ).  These two devices communicate with each other by handshaking. It allows a DTE and a DCE device system to acknowledge each other before sending the data.   

b) RS422

The RS422 Standard defines a serial communications standard. RS422 is a high speed and/or long distance data transmission.  Each signal is carried by a pair of wires and is thus a differential data transmission system.

The devices that relates are  the communication between DTE, data terminal equipment, and DCE, data communication equipment.  

Reference; 

SearchMobileComputing. (2017). IEEE 802 Wireless Standards: Fast Reference - Reference from WhatIs.com. [online] Available at: http://searchmobilecomputing.techtarget.com/definition/IEEE-802-Wireless-Standards-Fast-Reference [Accessed 12 Apr. 2017].

Protocols.netlab.uky.edu. (2017). [online] Available at: http://protocols.netlab.uky.edu/~calvert/classes/571/lectureslides/802overview.pdf [Accessed 12 Apr. 2017].

Techopedia.com. (2017). What is the IEEE 802.1 Working Group (IEEE 802.1)? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/19936/ieee-8021-working-group-ieee-8021 [Accessed 12 Apr. 2017].

Yourdictionary.com. (2017). 802.2 dictionary definition | 802.2 defined. [online] Available at: http://www.yourdictionary.com/802-2 [Accessed 12 Apr. 2017].

Techopedia.com. (2017). What is IEEE 802.3? - Definition from Techopedia. [online] Available at: https://www.techopedia.com/definition/19938/ieee-8023 [Accessed 12 Apr. 2017].

Yourdictionary.com. (2017). 802.4 dictionary definition | 802.4 defined. [online] Available at: http://www.yourdictionary.com/802-4 [Accessed 12 Apr. 2017].

Yourdictionary.com. (2017). 802.5 dictionary definition | 802.5 defined. [online] Available at: http://www.yourdictionary.com/802-5 [Accessed 12 Apr. 2017].

Yourdictionary.com. (2017). 802.7 dictionary definition | 802.7 defined. [online] Available at: http://www.yourdictionary.com/802-7 [Accessed 12 Apr. 2017].

Davis, C. and Davis, C. (2017). IEEE 802.8 Protocols | eHow. [online] eHow. Available at: http://www.ehow.com/list_7492144_ieee-8028-protocols.html [Accessed 12 Apr. 2017].

Yourdictionary.com. (2017). 802.9 dictionary definition | 802.9 defined. [online] Available at: http://www.yourdictionary.com/802-9 [Accessed 12 Apr. 2017].

Yourdictionary.com. (2017). 802.12 dictionary definition | 802.12 defined. [online] Available at: http://www.yourdictionary.com/802-12 [Accessed 12 Apr. 2017].

SearchMobileComputing. (2017). What is 802.16? - Definition from WhatIs.com. [online] Available at: http://searchmobilecomputing.techtarget.com/definition/80216 [Accessed 12 Apr. 2017].

SearchNetworking. (2017). What is Resilient Packet Ring (RPR)? - Definition from WhatIs.com. [online] Available at: http://searchnetworking.techtarget.com/definition/Resilient-Packet-Ring [Accessed 12 Apr. 2017].

Ieee802.org. (2017). [online] Available at: http://ieee802.org/misc-docs/GlobeCom2009/IEEE_802d18_and_d19_Kraemer.pdf [Accessed 12 Apr. 2017].

Ieee802.org. (2017). IEEE 802.19 Wireless Coexistence Working Group (WG). [online] Available at: http://www.ieee802.org/19/pub/TG1a.html [Accessed 12 Apr. 2017].

researchgate. (2017).https://www.researchgate.net/publication/3436161_IEEE_80220_Mobile_broadband_wireless_access [Accessed 12 Apr. 2017].

Ieee802.org. (2017). IEEE 802.21. [online] Available at: http://www.ieee802.org/21/ [Accessed 12 Apr. 2017].

Engineersgarage.com. (2017). What is RS232 Protocol: Basics, Implementation & Specification. [online] Available at: https://www.engineersgarage.com/articles/what-is-rs232 [Accessed 12 Apr. 2017].

Research the following protocols and for each protocol: 

State the full protocol name and briefly explain-how the protocol is used. 

HTTP :  HyperText Transfer Protocol. It is the protocol used to transfer data over the web. 

  ( Protocol used read the html language ) 

FTP :  File Transfer Protocol.  It is a protocol for transmitting files between computers on the Internet over IP connections.

  ( Sharing files to another ) 

IP :  Internet Protocol. It is a protocol by which data is sent from one computer to another on the Internet. 

  ( IP is network address. )

TCP : Transmission Control Protocol. A  network communication protocol designed to send data packets over the Internet.

  ( TCP  responsible data between IP and IP ) 

POP3 :  Post Office Protocol 3. It is protocol for delivering the e-mail messages.  A POP3 mail server receives e-mails and filters them into the appropriate user folders.

    ( POP 3 responsible of receiving the mail ) 

SMTP : Simple Mail Transfer Protocol. It is a protocol used in sending and receiving e-mail. It provides the ability to send and receive email messages.

   ( SMTP responsible for sending the email ) 

IMAP : Internet Message Access Protocol. It is a protocol for accessing email on a remote server from a local client. It is a method of accessing e-mail messages on a server without having to download them to your local hard drive. 

Briefly describe FIVE (5) main issues that must be addressed when designing computer networks.

Addressing – The message be specific where it will be send to . Such as by IP address.

Error control – Makes sure the message is send to the receiver.

Flow control – Matching the speed of the sender and receiver of the message so they have the same speed. 

Multiplexing – (Multi-sending) Dividing the messages from the senders so it can be received by receivers together and in the same time.

Routing – Using different paths but still have the same destination.

Briefly explain why networks are modeled as a stack of layers.

:  The networks are modeled as stack of layers because the process of the network work in layer from bottom layer to top layer, and it will process each on of the layer without any skip. Each layer had protocols (rules) and own well defined function.

Briefly describe the role of an interface when modeling a network as stack layers.

:  The role of an interface when modeling a network as stack layers is providing end-user meaning it’s user-friendly. 

Explain the role played by a session in a network connection.

: Role of session in network connection is to establishing process of communication between network hosts. (Multiplexing). Such as inter-host connection. 

State the SEVEN (7) layers of the OSI Reference Model in the correct order and briefly state the purpose of each layer.

Physical Layer - Transmitting bits (1s and Os) over communication channels. For example, 0110110110.

DataLink Layer - Establishing paths for data transfer through the network(routing). Such as logical Addressing.

Transport Layer - Delivering message between network hosts. 

Session Layer - Establishing process to process communication between the network hosts. 

Presentation Layer - Defining syntax which two network use to communication such as Operating System (OS)

Question 1:

Explain the OSI Model

The Open System Interconnection (OSI) Model is conceptual and logical layout of reference model on how network communication used by systems it implement protocols in seven layers.

Question 2:

Identify and explain the 7 layers of the OSI Model.

The purpose of the OSI reference model is to guide vendors and developers so the digital communication products and software programs they create will interoperate, and to facilitate clear comparisons among communications tools.

         Layer 1 – Physical Layer explain the electrical signals used for distribution of available communication resources. It is consolidate the hardware necessities of a network to facilitate the successful transmission rate to improve the flow of data between a sender and receiver.

p;Protocols of Physical Layer are CSMA (carrier sense multiple access), DSL (digital subscriber line) and RS-232.

          Layer 2 - Datalink Layer handles the moving of data in and out across a physical link in a network. The Data Link Layer divided into two sublayers, The Media Access Control (MAC) Sublayer and the Logical Link Control (LLC) Sublayer.

The protocols of Datalink Layer are Ethernet, Attached Resource Computer NETwork (ARCnet) and Cisco Discovery Protocol (CDP).

          Layer 3 - Network Layer is third level and bacbone of the Open Systems Interconnection Model (OSI Model). It selects and manages the best logical path for data transfer between nodes.

Protocols of Network Layer are Internet Protocol and Netware IPX/SPX.

          Layer 4 - Transport Layer provides for the transparent transfer of data for users, systems, and applications and reliable data transfer services to the upper levels. It ensures the reliable arrival of messages and provides error checking mechanisms and data flow controls.

Protocals of Transport Layer are Transmission Control Protocol (TCP) and User Datagram Protocol (UDP).

          Layer 5 - Session layer known as port layer manages the setting up and taking down of the association between two communicating end points that is called a connection. Protocols of Session Layer are X.225 or ISO 8327.

          Layer 6 - Presentation layer known as syntax layer. The presentation layer mainly translates data between the application layer and the network format. It is responsible for integrating all formats into a standard format for efficient and effective communication.

Protocol of Presentation Layer are XDR, TLS, SSL and MIME.

          Layer 7 - Application layer is the seventh layer of the OSI model and the only one that directly interacts with the end user. It defines how an application processes ensure the exchange data between programs running on the source and destination hosts.

Exercise 1

Research ONE social issue that that has arisen as the result of the implementation of computer networks. Explain what the issue is and describe how computer networks are the cause of the issue. Discuss the advantage and drawbacks of implementing such computer networks. Where possible use detail from newspaper or journal reports hat highlight relevant cases in the public. Spotlight.

Concerning for the social issues that was cause as the result of the implementation of computer networks. One of the social issues that highly need to be paid attention and should not be ignored is the privacy of information of the user. The increasing of the problem of identity theft and fraud have caused people to become more aware about how they will use their personal information, issues of privacy and lack of security for the computer network. This simply happen by the use of the computer network such as giving away private data of the user via chat, social media and etc. Not only by giving personal information but problem like cyber crime, computer network security and hacking can trouble the privacy. 

While computer network does not have any restrict uses, it does have advantage and disadvantage. One of advantages of computer network is file sharing. This provides people access to share their information, hence it significantly save time and effort. It increases the storage capacity with suitably to store all the data and files and it is inexpensive to set up. With increases storage capacity, it offers convenient resource sharing. Computer network offers the user flexibility without affecting its functionality in which enable the accessibility to the information. Lastly, main advantage of it is the easy communication efficiently using a network with people. And with existing of Computer network it enable the interaction by with sharing data, instant message, email and communication.

One of the major drawback of Computer network is the security difficulties that always occurs with large network. The cause of the security issues is mostly illegal activities and hacking. By using the computer network it causes people to dependent more to computer rather than doing their own effort. With large amount of people using computer network is not surprise for viruses spread to their devices and this usually happens storing a corrupted files into viruses. It can be prevent by installing anti-virus software in the computer.

Exercise 2

Research the international and national bodies that are responsible for developing and maintaining standards for telecommunication networks and the Internet. Name each body and briefly outline their responsibilities in your own word. 

International Organization for Standardization (ISO) responsible for the guidelines that ensure the products and services fit their requirement.

International Electrotechnical Commission (IEC) produce a standard for designing and manufacturing in various ways.

Pair with @zahirahhm

Examine the compute network in you laboratory:

a) List all items in the network

PC

Printer

Projector

Smartphone

CCTV

Tablet

Laptop

b) List all the communications between items in the network

Cables

Switches

Wireless

Bluetooth

Internet

IP Address

c) List the external network that the laboratory connects to

Switches

Cables and Connectors

Server

Protocol converter

Gateway

Firewall

Router

Monitors

d) Compare your list with the other groups

     compare with husnajs and wan group. 

e) Discuss the issues raised by networking these different devices and external networks

It can cause virus through the connection of network

Thus it slow down the performance of the interaction to allow the user  to access their devices and the network

The external networks products such as switches may be expensive to buy.

Introduction

I have been gone to varieties of website throughout my life. When it’s come to favorite website, I have to say I cannot choose any blog and what I normally do daily does not have anything that would really makes me wanted to state one particular website as favorite. 

1. sixpenceee.com

This website was run by a blogger who named was Sixpenceee. It has been surprisingly active for years. I got suggested this blog by my old friend when I’m still in high school. What I’d like about this website wasn’t the page layout of the website but the content of this blog. She was famous with posting and blogging creepiest, fact, history and science posts. It gave me thrilled every time I tried to visit this website. Honestly, I would love to recommend this blog to someone who’d loves things that wasn’t in this world. The link to the website will be here. 

2. IMVU

Not many people know about this, with hope that other people get expose to things that most unlikely been know such as an online metaverse and website . There are many ways on how this work. It can be played on browser or application by using any devices with the new updated. But I'd recommend to use the application, itself and installed it on laptop. Imvu is definitely similar with sims and yet the only thing is different are each account will have only one avatar, when needed certain product it can be obtain by coins with average of one product costing 1000 coins with that developing your own avatar, in imvu we can interact with other people all over the world, people can even have friendship, relationships, and even get married. I have been a user for almost a year and so far I'm still addicted to it. Below are pictures of IMVU using my avatar.

3. Kevin Richardson

Kevin Richardson was a man who known to be a lion whisper in South Africa. He inspired and teaches me that we should be respect the animals, prevents the extinction and learning more about wild animals especially the lions. He owned Kevin Richardson Wildlife Sanctuary relocated to Welgedacht Private Game Reserve near Pretoria. Richardson has worked with big cats and relies on intuition rather than static rules. He has slept next to, fed, and even lived with lions. Along with lions, he has worked with cheetahs, leopards, and hyenas. Though he prefers lions to any other big cat especially white lions. He has known all of the lions he works with since they were cubs and some were saved from captivity nor zoo. Thus overall he have my admiration and appreciation for saving the animals. In the future I'd love to donate him as much as I can to help the animals whether in term of medicine or even money. To check more about him click here.

3. Ava’s Demon