Section 4: TCP/IP Model

What do you do to the OSI model to make the TCP/IP model

squish top 3 layer and bottom 2 layers together

from top to bottom list the four layers of the TCP/IP model?

application

transport

internet

network interface

Which layer of the TCP/IP model is being described?

describes how to transmit bits across the network (1s and 0s)

determines how interface uses network medium such as coax, fiber, and twisted pair copper cables

describes how the medium will be constructed such as ring, FDDI ( fiber redundancy), etc.

Network interface ( layer 1 )

Which layer of the TCP/IP model is being described?

• packages data into IP datagrams

• contains source and destination IP addresses

• fowards datagrams between hosts across the networks

• routes IP datagrams across networks

• connectivity occurs externally i.e internal vs external

• examples: IP, ICMP, ARP, RARP

Internet ( layer 2 )

Which layer of the TCP/IP model is being described?

• the only layer that stays the same between OSI vs TCP/IP

• provides communication session management between hosts

• defines level of service and status of connection used for transport

• examples: tcp, udp, rtp

Which layer of the TCP/IP model is being described?

• defines tcp/ip application protocols

• defines how programs interface with the transport layer service

• layer with which the user interacts and sees

• examples : HTTP, TELNET, FTP, SNMP, DNS, SMTP, SSL, TLS

Application (layer 4)

What are the two categories of ports?

well known & reserved ports ( idk why they count as one together )

ephemeral ports

which type of port is being described?

ports 0 - 1023

well known or reserved ports

which type of port is being described?

short - lived transport port that is automatically selected from a predefined range

ports 1024-65,535

ephemeral ports

a port is a logical opening on a system representing a service or application true or false?

true

what four things make up IPV4 packets?

source address

destination address

IP flags

Protocol

IP flags allow what?

packet fragmentation

What are the five IP protocol types covered in this lesson?

TCP

UDP

ICMP

GRE

which IP protocol type is being described?

■ A transport protocol that operates at layer 4 of the OSI model

■ Used on top of the Internet Protocol for the reliable packet transmission

■ Operates by conducting a three-way handshake between a client and a

server, and then establishing the connection

■ considered a connection-oriented method of communication

Transmission Control Protocol (TCP)

which IP protocol type is being described?

■ Great for some applications, like streaming audio and video, but it definitely does NOT provide reliable delivery of the data

■ A lightweight data transport protocol that also works on top of IP

■ Can detect if its packets are corrupted when they are received by a client using a checksum, but there is no connection and no sequencing to the UDP segments

Fast

User Datagram Protocol (UDP)

which IP protocol type is being described?

■ A network level protocol that is used to communicate information about network connectivity issues back to the sender

■ used a lot by network technicians during troubleshooting, but it is also used by attackers to conduct ping scans and network mapping

Internet Control Message Protocol (ICMP)

which IP protocol type is being described?

■ A tunneling protocol that was developed by Cisco to encapsulate a wide variety of network layer protocols inside a virtual point-to-point or point to- multipoint link over an Internet Protocol network

■ Important to set a smaller maximum transmission unit or MTU size on the tunnel

■ It does not provide any encryption

Used to create a tunnel over a public network

Generic Routing Encapsulation (GRE) Protocol

which IP protocol type is being described?

■ Set of secure communication protocols at the network or packet processing layer that is used to protect data flows between peers

Internet Protocol Security (IPsec) Protocol

there are two protocols within IPsec. what are they?

Authenticiation Header ( AH )

Encapsulating Security Payload (ESP)

which part of IP sec is being described?

A protocol within IPSec that provides integrity and

authentication

Authentication Header (AH)

which part of IP sec is being described?

○ Provides encryption and integrity for the data packets sent over IPsec

○ Backwards-compatible with most IP routers including

those that were not designed to work with IPsec initially

Encapsulating Security Payload (ESP)

which protocol ( name and port # ) sends email from one server to the other?

SMTP (25)

Which protocol ( and port ) is a simple protocol that provides basic file transfer function with no user authentication

Trivial File Transfer Protocol (TFTP) 69