Net+ 4.1 Lesson

Answer

• Delivery address 

• Return address 

• Method of shipment (overnight, standard, etc.) 

• Content type (battery, fragile, perishable, etc.)

Shipping and Datagram

• Just as a package label includes the delivery address, return address, and other details to ensure it reaches the correct destination safely, the IPv4 Datagram Header contains specific information to ensure data travels correctly over the Internet. It's divided into several fields, each playing a crucial role. 

• The "Version" field tells us about the IP protocol version, like knowing whether you're sending a standard package or an overnight one. 

Drag and Drop

Just as a package label includes ​

Placeholder

, and other details to ensure it reaches the correct destination safely, the ​

Placeholder

contains specific information to ensure data travels correctly over the Internet. It's divided into several fields, each playing a crucial role. The "​

Placeholder

" field tells us about the IP protocol version, like knowing whether you're sending a standard package or an overnight one. 

Drag these tiles and drop them in the correct blank above

the delivery address, return address

IPv4 Datagram Header

Version

Shipping and Datagram

• The "Source IP Address" and "Destination IP Address" are akin to the sender's and receiver’s addresses on a package, ensuring the data is sent from the right starting point to the correct destination. 

• Just as knowing whether a package contains perishable goods might dictate how it's handled, the "Protocol" field ensures data packets are processed correctly, based on the requirements of the specified protocol.

Dropdown

The "Source IP Address" and "Destination IP Address" are akin to the ​

Select answer

, ensuring the data is sent from the right starting point to the correct destination. 



Just as knowing whether a package contains perishable goods might dictate how it's handled, the "​

Select answer

" field ensures data packets are processed correctly, based on the requirements of the specified protocol.

IP header

• Version – The IP protocol version (4 or 6)

• Header length – The number of 32-bit words in the header (minimum value of 5)

• Differentiated Services Code Point (DSCP) – The type of service for differentiated service

Dropdown

​

Select answer

– The IP protocol version (4 or 6)



​

Select answer

– The number of 32-bit words in the header (minimum value of 5)



​

Select answer

– The type of service for differentiated service

IP header

• Total length – Total size of the datagram including the header and the data segment 

• Checksum – Provides error detection for the header 

• Protocol – The type of data encapsulated in the payload

Dropdown

​

Select answer

– Total size of the datagram including the header and the data segment 



​

Select answer

– Provides error detection for the header 



​

Select answer

– The type of data encapsulated in the payload

L2 v L3

Forwarding at layer 3 is referred to as routing, while forwarding at layer 2 is described as switching.

Routing and Switching

• How routing and switching work together on a typical network

  • Network is connected to the Internet through WAN interface on router 

  • Router’s other interfaces divide the network into 3 logical subnets that are mapped to layer 2 segments, each implemented with a switch. 

  • Nodes within each subnet can address one another directly because they are in the same broadcast domain

  • Nodes within the subnet can only communicate with nodes in other subnets through the router

Multiple Choice

Typically, what device will connect to the WAN?

• Router
• Modem
• Switch
• Access Point

Multiple Choice

Typically, a device that uses L2 mostly and connects nodes together is known as

• router
• hub
• bridge
• switch

Multiple Choice

A L3 device that can help segmented networks communicate is known as

• switch
• hub
• bridge
• router

Multiple Choice

In some cases, a switching device can perform L3 roles.

• No, switching devices cannot perform L3 roles.
• Yes, some switching devices can perform L3 roles.
• Only routers can perform L3 roles, not switches.
• Switching devices only operate at Layer 1.

ARP

• Similar to how the Address Resolution Protocol (ARP) functions within a network, envision someone attempting to deliver flowers to an individual’s workplace. 

  • The sender knows who they are delivering to (IP address) but not their exact location within the large office building (the MAC address). 

  • The reception desk acts like ARP in this scenario. 

  • The delivery person approaches with a name, asking, “Can you tell me where I can find this person?” 

  • The receptionist, having access to the internal “directory” of where everyone is located (similar to how ARP knows the physical MAC addresses associated with IP addresses), provides the specific desk location (the MAC address). 

Multiple Choice

The role of ARP within a network is to

• convert MAC addresses to IP addresses
• filter network traffic
• encrypt data packets
• map IP addresses to MAC addresses

ARP

• When both sending and receiving hosts are within the same broadcast domain, or subnet, local address resolution takes place using ARP requests and replies.

• If the destination address is on another subnet or a remote network, the local host uses ARP to determine the MAC address of the default gateway and forwards the packet.

Multiple Choice

When ARP is used to communicate with a host on a different subnet, the MAC address of what device will reply.

• The MAC address of the switch will reply.
• The MAC address of the default gateway (router) will reply.
• The MAC address of the DNS server will reply.
• The MAC address of the destination host will reply.

Multiple Choice

On the local subnet, an ARP request from one host will return what?

• The broadcast address of the local subnet.
• The hostname of the requested IP address.
• The MAC address of the host that owns the requested IP address.
• The IP address of the host that owns the requested MAC address.

Unicast/Broadcast

• Unicast can be remembered as a "one-to-one" form of communication, similar to sending a letter directly to a friend; it's designated for a single, specific recipient.

Unicast/Broadcast

• Broadcast communication functions akin to shouting in a crowded room; anyone within earshot can hear the message. It is the digital equivalent of sending out a public announcement over a loudspeaker, targeting everyone in a specific area or network subnet, regardless of whether they need the information. This method ensures that all connected devices are simultaneously informed, suitable for network management tasks like searching for servers or updating multiple systems at once.

Multiple Choice

When one host communicates directly with another host, what addressing is this considered?

• Unicast addressing

• Multicast addressing
• Indirect addressing
• Broadcast addressing

Multiple Choice

When one host sends a message to all hosts regardless of who actually needs the message, this is known as what kind of addressing?

• Anycast
• Multicast
• Unicast
• Broadcasting

Multicast / Anycast

Multicast is like a seminar where only registered attendees are privy to the information being disseminated. It targets a select group of interested parties, efficiently distributing data to multiple recipients without cluttering the network. This approach is perfect for applications requiring simultaneous data delivery like live video streaming or financial stock update broadcasts, ensuring that only interested or relevant recipients receive the message.

Multicast / Anycast

Anycast can be likened to a chain of retail stores, where despite the presence of multiple locations, a customer only visits the one nearest to them for convenience. In network terms, anycast addresses data requests to the closest or most accessible server among a group of potential servers, prioritizing speed and efficiency. This method is particularly effective in distributed networks for enhancing user experience by reducing latency, improving load distribution, and providing redundancy.

Multiple Choice

Which type of addressing targets a specific group of hosts predetermined by the network administrator; this ensures only those in the group get the data.

• Broadcast addressing
• Multicast addressing
• Anycast addressing
• Unicast addressing

Multiple Choice

This type of addressing reduces latency and improves network efficiency by allowing hosts to communicate with the closest servers.

• Broadcast
• Unicast
• Multicast
• Anycast

Let's Review

Multiple Choice

When one host communicates directly with another host, what addressing is this considered?

• Unicast addressing

• Multicast addressing
• Indirect addressing
• Broadcast addressing

Drag and Drop

Just as a package label includes ​

Placeholder

, and other details to ensure it reaches the correct destination safely, the ​

Placeholder

contains specific information to ensure data travels correctly over the Internet. It's divided into several fields, each playing a crucial role. The "​

Placeholder

" field tells us about the IP protocol version, like knowing whether you're sending a standard package or an overnight one. 

Drag these tiles and drop them in the correct blank above

the delivery address, return address

IPv4 Datagram Header

Version

Multiple Choice

Typically, what device will connect to the WAN?

• Router
• Modem
• Switch
• Access Point

Multiple Choice

A L3 device that can help segmented networks communicate is known as

• switch
• hub
• bridge
• router

Multiple Choice

The role of ARP within a network is to

• convert MAC addresses to IP addresses
• filter network traffic
• encrypt data packets
• map IP addresses to MAC addresses