ist201 test 3 study guide

stateful

A ________ protocol is a protocol that keeps track of the state of the communication session.

socket

A __________ is a combination of the source IP address and source port or the destination IP address and the destination port number.

gateway

A computer that connects to any network outside its own broadcast domain needs a default _______ in order to deliver packets.

broadcast, multicast, unicast

A host can communicate in an IPv4 network three ways A directed ___[a]___ is a message sent to all hosts on a specific network. It is useful for sending a message to all hosts on a nonlocal network. A ___[b]___ message is a message sent to a selected group of hosts that are part of a subscribing group. A limited broadcast is used for a communication that is limited to the hosts on the local network. A ___[c]___ message is a message sent from one host to another.

onversation

A socket pair identifies the specific _______________ between the two hosts.

two, mask

An IPv4 address is divided into ___[a]___ parts: network portion - to identify the specific network on which a host resides host portion - to identify specific hosts on a network. A subnet ___[b]___ is used to identify the length of each portion

ipv6 unicast-routing

An router becomes a member the All-routers multicast group when it is enabled as an IPv6 router with the ______________ global configuration command.

True

Applications using UDP must implement their own reliability, if needed.

sessions, Because UDP is connectionless, sessions are not established before communication takes place as they are with TCP. UDP is said to be transaction-based; that is, when an application has data to send, it simply sends the data.

Because UDP is connectionless, _________ are not established before communication takes place as they are with TCP.

Destination IP address-

Contains a 32-bit binary value that represents the destination IP address of the packet

Source IP Address-

Contains a 32-bit binary value that represents the source IP address of the packet

Version-

Contains a 4-bit binary value identifying the IP packet version. For IPv4 packets, this field is always set to 0100

Time-to-Live(TTL)

Contains an 8-bit binary value that is used to limit the life-time of a packet. It is specified in seconds but is commonly referred to as hop count. The packet sender sets the initial time-to-live value and is decreased by 1 each time the packet is processed by a router, or hop.

nodes

FF02::1 is the all-__________ multicast group within the scope of the local link.

routing table, Hosts must maintain their own local routing table to ensure that network layer packets are directed to the correct destination network. This local table typically contains a route to the loopback interface, a route to the network that the host is connected to, and a local default route, which represents the route that packets must take to reach all remote network addresses.

Hosts must maintain their own local ___________ to ensure that network layer packets are directed to the correct destination network.

hexadecimal

IPv6 addresses are represented by __________ numbers and are 128 bits in length.

No. NAT is not needed because of the large number of public IPv6 addresses. Customer sites, from the largest enterprises to single households, can get a public IPv6 network address.. This avoids some of the NAT-induced application problems experienced by applications requiring end-to-end connectivity.

IS NAT needed for IPV6?

Destination port (16 bits)

Identifies the Receiving Port.

Source port (16 bits)

Identifies the Sending Computer's TCP Port.

TFTP, ROM

If the IOS image is not located in flash, then the router may look for it using a [a] server. If a full IOS image cannot be located, a scaled-down version of the IOS is copied from [b] into RAM. This version of IOS is used to help diagnose any problems and can be used to load a complete version of the IOS into RAM.

1. Connection-oriented conversations by establishing sessions. Negotiates and establishes a permanent connection between source and destination devices prior to forwarding any traffic. Session establishment prepares the devices to communicate with one another. 2. Reliable delivery. It is possible for a piece of data to become corrupted, or lost completely, as it is transmitted over the network. TCP can ensure that all pieces reach their destination by having the source device retransmit lost or corrupted data. 3.ordered data reconstruction. By numbering and sequencing the segments, TCP can ensure that these segments are reassembled in the proper order. 4. Flow Control. When TCP is aware that resources are overtaxed, it can request that the sending application reduce the rate of data flow.

In addition to supporting the basic functions of data segmentation and reassembly, TCP also provides:

Control bits (6 bits)

Includes bit codes, or flags, that indicate the purpose and function of the TCP segment

Urgent (16 bits)

Indicates if data is urgent

Acknowledgement number (32 bits)

Indicates the data that has been received.

Window size (16 bits)

Indicates the number of segments that can be accepted at one time.

Header length (4 bits)

Known as ʺdata offsetʺ. Indicates the length of the TCP segment header.

URG- urgent pointer field significant ACK- acknowledgement field significant PSH- push function RST-reset the connection SYN- synchronize sequence numbers FIN- No more data from sender

List and Describe the TCP Header Control Bit Flags presented in the chapter.

Version- This field contains a 4-bit binary value identifying the IP packet version. For IPv6 packets, this field is always set to 0110 Traffic Class- This 8-bit field is equivalent to the IPv4 Differentiated Services field. It also contains a 6-bit Differentiated Services Code Point value used to classify packets and a 2-bit Explicit Congestion Notification used for traffic congestion control. Flow Label- This 20-bit field provides a special service for real-time applications. It can be used to inform routers and switches to maintain the same path for the packet flow so that packets are not reordered. Payload Length- This 16-bit field is equivalent to the Total Length field in the IPv4 header. It defines the entire packet size, including header and optional extensions. Next Header- This 8-bit field is equivalent to the IPv4 Protocol field. It indicates the data payload type that the packet is carrying, enabling the network layer to pass the data to the appropriate upper-layer protocol. This field is also used if there are optional extension headers added to the IPv6 packet. Hop Limit- This 8-bit field replaces the IPv4 TTL field. This value is decremented by 1 by each router that forward the packet. When the counter reaches zero , the packet is discarded and an ICMPv6 message is forwarded to the sending host, indicating that the packet did not reach its destination. Source Address- This 128-bit field identifies the IPv6 address of the receiving host. Destination Address- This 128-bit field identifies the IPv6 address of the receiving host.

List and Describe the fields in the IPv6 packet header:

Connectionless: No connection with the destination is established before sending data packets. Best effort (unreliable): Packet delivery is not guaranteed. Media independent: Operation is independent of the medium carrying the data.

List and Describe the three basic characteristics of IP:

Version- Contains a 4-bit binary value identifying the IP packet version. For IPv4 packets, this field is always set to 0100. pg 291 Differentiated Services- formerly called the Type of Service field. The DS field is an 8-bit field used to determine the priority of each packet. The first 6 bits identify the Differentiated Services Code Point value that is used by a quality of service mechanism. The last 2 bits identify the explicit congestion notification value that can be used to prevent dropped packets during times of network congestion.(291) Time-to-Live(TTL)- Contains an 8-bit binary value that is used to limit the life-time of a packet. It is specified in seconds but is commonly referred to as hop count. The packet sender sets the initial time-to-live value and is decreased by 1 each time the packet is processed by a router, or hop. (pg292) Protocol- This 8-bit binary value indicates the data payload type that the packet is carrying, which enables the network layer to pass the data to the appropriate upper-layer protocol. (pg292) Source IP Address- Contains a 32-bit binary value that represents the source IP address of the packet (pg292) Destination IP address- Contains a 32-bit binary value that represents the destination IP address of the packet (pg292) Internet header length(IHL)- contains a 4-bit binary value identifying the number of 32-bit words in the header. The IHL value varies because of the Options and Padding fields. (pg293) Total length- Sometimes referred to as the Packet Length, this 16-bit field defines the entire packet size, including header and data, in bytes. (pg 293) Header Checksum: The 16-bit field is used for error checking of the IP header. The checksum of the header is recalculated and compared to the value in the checksum field. If the values do not match, the packet is discarded. (pg293) Identification- This 16-bit field uniquely identifies the fragment of an original IP packet. (pg293) Flags-This 3-bit field identifies how the packet is fragmented. It is used with the Fragment Offset and Identification fields to help reconstruct the fragment into the original packet. (pg293) Fragment Offset-This 13-bit field identifies the order in which to place the packet fragment in the reconstruction of the original unfragmented packet.(pg293) The options and Padding fields are rarely used and beyond the scope of this chapter. (pg293) The first 3 listed identify various settings of the IP packet. The 2 most commonly referenced fields are the source and destination IP addresses. These fields identify where the packet is from and where it is going. Typically these addresses do not change while traveling from the source to the destination. The remaining fields are used to identify and validate the packet, or to reorder a fragmented packet. Identification, Flags, and Fragment Offset keep track of the fragments. (pg291-293

List and Explain the IPv4 Header fields NOTE: I am expecting 12-14 fields based upon interpetation, research, and reading. Be specific on your list; note all sources for full credit.

Global routing prefix- is the prefix, or network, portion of the address that is assigned by the provider, such as an ISP, to a customer or site Subnet ID-used by an organization to identify subnets within its site Interface ID- equivalent to the host portion of an IPv4 address. used because a single host can have multiple interfaces, each having one or more IPv6 addresses

List and describe the three parts of an IPv6 global unicast address:

Global Unicast- similar to a public IPv4 address. These are globally unique, Internet routable addresses. Can be configured statically or assigned dynamically. Link Local- used to communicate with other devices on the same local link. they are confined to a single link. Loopback- used by a host to send a packet to itself and cannot be assigned to a physical interface. Unspecified Address- an all-0s address represented in the compressed format as ::/128 or just :: in the compressed format. it cannot be assigned to an interface and is only to be used as a source address in an IPv6 packet. Unique Local- used for local addressing within a site or between a limited number of sites. IPv4 embedded- used to help transition from IPv4 to IPv6.

List and describe the types of IPv6 unicast addresses:

Option1- SLAAC only: The device should use the prefix, prefix length, and default gateway address information contained in the RA message Option2-SLAAC and DHCPv6- The device should use the prefix, prefix length, and default gateway address information in the RA message. other information available, such as the DNS server address. Option3- DHCPv6 only- The device should not use the information in this RA message for its addressing information. Instead, the device will use the normal process of discovering and querying a DHCPv6 server to obtain all its addressing information.

List the common message types of ICMPv6

Connectionless: three basic characteristics of IP:

No connection with the destination is established before sending data packets.

FIN-

No more data from sender

print, netstat On a Windows host, the route print or netstat -r commands can be used to display the host routing table. Both commands generate the same output. On a router, the show ip route command is used to display the routing table. The netstat -s command is used to display per-protocol statistics. The tracert command is used to display the path that a packet travels to its destination.

On a Windows host, the route ___[A]___ or ___[B]___ -r commands can be used to display the host routing table.

False: In addition to being configured with the no shutdown command, a configured interface must also be connected to another device in order for the physical layer to be active

Once the no shutdown command is given, a router interface is active and operational.

Media independent: three basic characteristics of IP:

Operation is independent of the medium carrying the data.

Best effort (unreliable): three basic characteristics of IP:

Packet delivery is not guaranteed.

Packet buffer

Packets are temporarily stored in a buffer when received on an interface or before they exit an interface.

Retransmissions

Part of the additional overhead of using TCP is the network traffic generated by acknowledgements and ___________

Basic diagnostic software

Performs the power-on self-test (POST) of all components.

False

Ping is a testing utility that uses DNS echo request and echo reply messages to test connectivity between hosts. Ping works with both IPv4 and IPv6 hosts

Services Code

Point value used to classify packets and a 2-bit Explicit Congestion Notification used for traffic congestion control.

Limited IOS

Provides a limited backup version of the OS, in case the router cannot load the full featured IOS.

Bootup instructions

Provides the startup instructions

copy running-config startup-config command

R1# prompt

interface fastethernet 0/0 command

R1(config)# prompt

login command

R1(config-line)# prompt

enable command

R1> prompt

directly connected route: Routers add a directly connected route when an interface is configured with an IP address and is activated.

Routers add a ____________________ when an interface is configured with an IP address and is activated.

Total length-

Sometimes referred to as the Packet Length, this 16-bit field defines the entire packet size, including header and data, in bytes.

false, TCP uses the SYN and ACK flags in order to establish connectivity between two network devices.

TCP uses the SYN, ISN, and ACK flags in order to establish connectivity between two network devices.

three-way handshake

TCP uses the _______________ to ensure there is connectivity between the source and destination devices before transmission occurs.

Header Checksum:

The 16-bit field is used for error checking of the IP header. The checksum of the header is recalculated and compared to the value in the checksum field. If the values do not match, the packet is discarded.

Cisco IOS

The IOS is copied into RAM during bootup.

::1

The IPv6 address _______ is the loopback address.

Netstat

The ________ command should be used to examine the open connections on a host when performance appears to be compromised

Tunneling

The _________ migration technique encapsulates an IPv6 packet inside an IPv4 packet.

enable secret

The ____________ command is used to apply an encrypted password used on the router to access the privileged mode.

Dual-Stack

The _____________ migration technique allows IPv4 and IPv6 protocol stacks to coexist on the same network simultaneously.

copy running-config startup-config, The copy running-config startup-config command would take the configuration in RAM and update the configuration in NVRAM copy system:running-config nvram:startup-config, Note The copy running-config startup-config command has been replaced by the command shown here. However, the copy running-config startup-config command will continue to be supported as a command alias for the copy system:running-config nvram:startup-config command.

The ______________ command would take the configuration in RAM and update the configuration in NVRAM

Option3- DHCPv6 only-

The device should not use the information in this RA message for its addressing information. Instead, the device will use the normal process of discovering and querying a DHCPv6 server to obtain all its addressing information.

Option1- SLAAC only:

The device should use the prefix, prefix length, and default gateway address information contained in the RA message

Option2-SLAAC and DHCPv6

The device should use the prefix, prefix length, and default gateway address information in the RA message. other information available, such as the DNS server address.

True

The dynamic increasing and decreasing of window size is a continuous process in TCP

255,255,255,255

The limited broadcast is used for communication that is limited to the hosts on the local network. These packets always use a destination IPv4 address [a].[b].[c.].[d]

hop

The packet sender sets the initial time-to-live (TTL) value and is decreased by one each time the packet is processed by a router, or __________.

Datagrams

The pieces of communication in UDP are called _______

27

The prefix length notation for the subnet mask 255.255.255.224 is /_____

brief

The show interfaces command provides detailed interface statistics, whereas the show ip interface _____ command provides a summary of the interfaces, addressing, and current operational status

Tracking, Acknowledging, Retransmitting

The three basic TCP operations of reliability are: ___[a]___ transmitted data segments ___[b]___ received data ___[c]___ any unacknowledged data

Startup configuration file

The two primary files needed for bootup are the IOS image file and _______________________, which are copied into RAM to maximize performance.

1023

There are three ranges of TCP and UDP ports. The well-know range of port numbers is from port 0 (zero) to port number ______

Destination Address

This 128-bit field identifies the IPv6 address of the receiving host.

Source Address-

This 128-bit field identifies the IPv6 address of the receiving host.

Fragment Offset

This 13-bit field identifies the order in which to place the packet fragment in the reconstruction of the original unfragmented packet

Payload Length-

This 16-bit field is equivalent to the Total Length field in the IPv4 header. It defines the entire packet size, including header and optional extensions.

Identification-

This 16-bit field uniquely identifies the fragment of an original IP packet.

Flow Label-

This 20-bit field provides a special service for real-time applications. It can be used to inform routers and switches to maintain the same path for the packet flow so that packets are not reordered.

Flags-

This 3-bit field identifies how the packet is fragmented. It is used with the Fragment Offset and Identification fields to help reconstruct the fragment into the original packet

Protocol-

This 8-bit binary value indicates the data payload type that the packet is carrying, which enables the network layer to pass the data to the appropriate upper-layer protocol.

Traffic Class-

This 8-bit field is equivalent to the IPv4 Differentiated Services field. It also contains a 6-bit Differentiated

Next Header-

This 8-bit field is equivalent to the IPv4 Protocol field. It indicates the data payload type that the packet is carrying, enabling the network layer to pass the data to the appropriate upper-layer protocol. This field is also used if there are optional extension headers added to the IPv6 packet.

Hop Limit-

This 8-bit field replaces the IPv4 TTL field. This value is decremented by 1 by each router that forward the packet. When the counter reaches zero , the packet is discarded and an ICMPv6 message is forwarded to the sending host, indicating that the packet did not reach its destination.

ARP cache

This cache contains the IPv4 address to MAC address mappings, similar to the Address Resolution Protocol (ARP) cache on a PC. The ARP cache is used on routers that have LAN interfaces, such as Ethernet interfaces.

Version-

This field contains a 4-bit binary value identifying the IP packet version. For IPv6 packets, this field is always set to 0110

Reserved (6 bits)

This field is set aside for the future.

IP routing table

This file stores information about directly-connected and remote networks. It is used to determine the best path to use to forward packets.

Running configuration file

This is the configuration file that stores the configuration commands that the router IOS is currently using. It is also known as the running-config.

four

To terminate a single conversation supported by TCP, ______ exchanges are needed

hop limit

Traceroute makes use of a function of the TTL field in IPv4 and the __________ field in IPv6 in the Layer 3 headers, along with the ICMP time exceeded message.

best-effort

UDP is considered a ______________ transport protocol.

False, UDP does not reorder the data. If necessary, UDP relies on the upper-layer protocols for reordering of the data.

UDP reorders data, if necessary

Sequence number (32 bits)

Used for data reassembly purposes.

Checksum (16 bits)

Used for error checking of the segment header and data.

Telnet, SSH

What interface(s) uses the VTY lines to configure a router?

243

What is the decimal equivalent of the hex number 0xF3?

True

When a host needs to find the MAC address of a destination host, the IPv6 host device will send a neighbor solicitation (NS) message to the solicited node multicast address.

FE80::2AA:FF:FE9A:4CA3

Which IPv6 address is most compressed for the full FE80:0:0:0:2AA:FF:FE9A:4CA3 address?

Network Address Translation, hidden, connectivity

___[a]_____ is a technology commonly implemented within IPv4 networks that provides a way for multiple devices to share a single public IP address. However, because the public IP address is shared, the IP address of an internal network host is ___[b]___. This can be problematic for technologies that require end-to-end ____[c]____.

Encapsulation

____ assembles a message and adds information to each layer in order to transmit the data over the network

Source

____ port numbers are randomly generated.

Translation

_____ is a migration technique that allows IPv6-enabled devices to communicate with IPv4-enabled devices using a translation technique similar to NAT for IPv4

differentiated services

_____ is the IPv4 header field that is used to define the priority of each packet.

Read-only memory

______ is the nonvolatile memory where the diagnostic software, the bootup instructions, and a limited IOS are stored.

Port

_______ numbers are used to pass data streams to their proper applications

Sequence

_______ numbers indicate how to reassemble and reorder received segments.

window

_______ size is used to slow down the rate of data communication.

Multiplexing

________ is useful for interleaving multiple communication streams.

Acknowledgements

_________ are used to notify a sending device that a stream of data packets has or has not been received.

ACK

acknowledgement field significant

Unspecified Address-

an all-0s address represented in the compressed format as ::/128 or just :: in the compressed format. it cannot be assigned to an interface and is only to be used as a source address in an IPv6 packet.

Internet header length(IHL)-

contains a 4-bit binary value identifying the number of 32-bit words in the header. The IHL value varies because of the Options and Padding fields.

Interface ID

equivalent to the host portion of an IPv4 address. used because a single host can have multiple interfaces, each having one or more IPv6 addresses

TCP uses the ACK number sent back to the source to indicate the next byte that the receiver expects to receive. This is called ___________ acknowledgement.

expectational

Differentiated Services-

formerly called the Type of Service field. The DS field is an 8-bit field used to determine the priority of each packet. The first 6 bits identify the Differentiated Services Code Point value that is used by a quality of service mechanism. The last 2 bits identify the explicit congestion notification value that can be used to prevent dropped packets during times of network congestion.

Global routing prefix-

is the prefix, or network, portion of the address that is assigned by the provider, such as an ISP, to a customer or site

PSH

push function

RST

reset the connection

Global Unicast-

similar to a public IPv4 address. These are globally unique, Internet routable addresses. Can be configured statically or assigned dynamically.

SYN

synchronize sequence numbers

URG

urgent pointer field significant

Loopback

used by a host to send a packet to itself and cannot be assigned to a physical interface.

Subnet ID

used by an organization to identify subnets within its site

Unique Local-

used for local addressing within a site or between a limited number of sites.

Link Local-

used to communicate with other devices on the same local link. they are confined to a single link.

IPv4 embedded

used to help transition from IPv4 to IPv6.