DCO/N - Protocols with Packet Analysis

The 'hop count' of the datagram. Limits datagram life.

Time To Live (TTL)

If the FIN and ACK flags are set in a TCP Header, what would the hexadecimal representation be?

0x11

The three items that ICMP can report are:

1. Dropped Packets (When packets arrive too fast to process) 2. Connectivity Failure (When a destination host cannot be reached) 3. Redirection (When a packet is instructed to use another router)

What are the five different ICMPv6 packet types used by Neighbor Discovery Protocol (NDP)?

1. Router Solicitation (RS) 2. Router Advertisement (RA) 3. Neighbor Solicitation (NS) 4. Neighbor Advertisement (NA) 5. Redirect Messages

What three protocols are used during the electronic mail transfer process?

1. Simple Mail Transfer Protocol (SMTP) 2. Post Office Protocol (POP) 3. Internet Message Access Protocol (IMAP)

A Target Protocol Address of "C0 A8 01 01" in hex is what converted to decimal?

192.168.1.1

What is a packet?

A packet is a basic unit of communication over a digital network. A packet is also called a datagram, a segment, a block, a cell or a frame, depending on the protocol used for the transmission of data.

What protocol is used to map known IP addresses to MAC addresses?

Address Resolution Protocol (ARP): · Uses a "Request and Reply" process. · ARP and broadcasts are nonexistent in IPv6.

Length of the header in 32-bit words

Data Offset

Used to help with the issue of memorizing IP Addresses by keeping a database of friendly names like "www.google.com" and logical names like "8.8.8.8", so it can resolve a friendly name with a logical one.

Domain Name System (DNS)

Provides a host the ability to check whether or not its link-local or global addresses are already in use on the network.

Duplicate Address Detection (DAD)

A protocol used to assign IP addresses to the hosts on our network. It also provides us other network addresses such as the subnet mask, our assigned default gateway, domain name and informs us of any local DNS servers.

Dynamic Host Configuration Protocol (DHCP)

Commonly used for exchanging files over the Internet. It is a client-server protocol relying on two communication channels: one to control the conversation and the other to transmit the data.

File Transfer Protocol (FTP)

Replaces the TTL field of IPv4. Decremented by one at each intermediate node visited by the packet. When it reaches 0 the packet is discarded.

Hop Limit

operates over TCP port 80 and is used to deliver data such as files, images, and media on the World Wide Web.

Hyper Text Transfer Protocol (HTTP)

Operates over TCP port 443 and typically uses the Secure Socket Layer (SSL) to encrypt its traffic.

Hyper Text Transfer Protocol Secured (HTTPS)

Used to test the basic connectivity of an IP network. It is responsible for providing information regarding the availability of devices on a network and reporting it.

Internet Control Message Protocol (ICMP)

Governed by RFC 4443, this provides troubleshooting for facilities and error reporting for undeliverable packets in IPV6.

Internet Control Message Protocol Version 6 (ICMPv6)

These messages are sent when there is a change in the link-layer address of a node on the local network. This is the response to Neighbor Solicitation (NS).

Neighbor Advertisement (NA)

What protocol replaces ARP in IPV6?

Neighbor Discovery Protocol (NDP)

Allows a host to find the Data link-layer address of its neighbor. To perform this function, the host will send out a message via a unicast configured IPv6 address to its neighbor's solicited-node multicast address.

Neighbor Solicitation (NS)

A program that allows applications on different computers to communicate within a local area network. It helps free the applications from having to understand the details of the network, including error recovery.

Network Basic Input/Output System (NetBIOS)

The process of capturing and interpreting live data as it flows across a network in order to better understand what is happening on that network.

Packet Analysis

Informs hosts of a better first-hop node on the path to a specific destination. Only IPv6 routers will send these out.

Redirect Messages

A protocol that a program can use to request a service from another program hosted on a different computer without needing to understand the details of the network.

Remote Procedure Call (RPC)

A formal document from the Internet Engineering Task Force (IETF) that is the result of committee drafting and subsequent review by interested parties.

Request for Comments (RFC)

These are sent out by IPv6 routers periodically and in response to solicitations.

Router Advertisement (RA)

This multicast will find any available IPv6 routers on the local network. If found, the IPv6 router will send back a Router Advertisement.

Router Solicitation (RS)

A protocol allowing a secure connection between computers and operates on TCP port 22.

Secure Shell (SSH)

What protocol is used for file sharing and contains a session control packet, file access packet, and general message packet?

Server Message Block (SMB)

A standard for electronic mail transmission across IP networks.

Simple Mail Transfer Protocol (SMTP)

In ___________ __________, the router will respond to the initial request with its link-local address only and lets the host know to contact the local DHCPv6 server for all other information.

Stateful DHCPv6

Uses stateless addressing, meaning no one is tracking what IP address each host is using.

Stateless Address Auto-configuration (SLAAC)

What are the steps to a TCP handshake?

TLDR: SYN, SYN-ACK, ACK First, Host A will send a TCP packet to Host B, with no information except the "SYN" flag and a random sequence number "X" Second, Host B will receive this packet and respond with a similar packet with the "SYNACK" flag set. It will also send two sequence numbers: the "ACK" will be "X+1" to show that it is in response to the original "X" and a "SYN" number "Y" Finally, Host A will respond to the "SYN-ACK" with its own "ACK" and a sequence number of "Y+1" to show it is responding to the specific "SYN-ACK" sent from Host B

Enables terminals and terminal-oriented processes to communicate on a network running TCP/IP. Its overall function is to provide an unsecure means by which a user on one machine can access, and use, another machine as if it was directly connected. Runs over TCP port 23.

Telnet

At its core, provides node-to-node data transfer—a link between two directly connected nodes. It ensures that the data being transmitted is delivered to the proper device and translates the data into bits for the Physical Layer to transmit.

The Data Link Layer

What happens when a DNS server cannot resolve an IP address with its own database and needs to ask other DNS servers for the information?

This process is called DNS recursion. When a DNS server does not have the information being requested, it will query other DNS servers in a hierarchical fashion until it gets the information it needs.

Provides end-to-end reliability for the delivery of data. Handles data sequencing and error recovery, and ensures data gets where it is supposed to go.

Transmission Control Protocol (TCP)

Aims to provide speedy transmission. This will most likely be used for services like audio or visual.

User Datagram Protocol (UDP)

What is a protocol of "11" in an IPv4 Header?

User Datagram Protocol (UDP)

What protocol is used mostly for audio or visual traffic?

User Datagram Protocol (UDP)