tcp/ip terms lab 1

ARP Hardware Type for Ethernet

0x0001

What is ARP IP protocol type?

0x0800

What are ARP MAC and IP address length?

6 bytes and 6 bytes

A tcp/ip application layer that resolves symbolic names into IP addresses.

DNS

A tcp/ip protocol that defines messages used by devices to assist data packet delivery via event and error notifications.

ICMP

A tcp/ip internet layer protocol that provides packaging for upper layer data and uses its own hierarchical logical addressing scheme.

IP

What are some important Internet Layer Technologies?

IP, ICMP, Packets, Fragmentation, Routing, Logical Addressing

Technologies that are in the Internet Layer

IP, Packet, ICMP, Fragmentation, Routing, Logical Addresses

A type of data transport that ensures delivery using acknowledgements, flow control, sequencing, and formal connection between computers. Its drawback is substantial communications overhead.

connection oriented

A type of data transport that doesn't guarantee delivery of data, with the benefit of minimal communications overhead.

connectionless

A name for tcp/ip Transport layer PDU used by connectionless protocols.

datagram

Common name for ports in the range 49152-65535

dynamic ports

What is ICMP's general use?

not to transport application data. It is instead used by network devices to exchange error or event information.

A name for tcp/ip Internet layer PDU

packet

An address type that allows for unique identification of a host within a physical segment, enabling hop-to-hop delivery of data.

physical address

A mechanism that allows for multiplexing outbound data from services into TCP or UDP stream at the sending computer as well as demultiplexing this data at the receiving computer.

port numbers

What is UDP's general use?

to be an unreliable, but a low processing protocol that handles data delivery made by software applications. It then encapsulates the data into datagrams and passes it on to layer 2

Which TCP/IP protocols operate at the Transport Layer

UDP, TCP

Technologies that are in the Transport Layer

UDP, TCP, Datagram, Segment, Ports, Connection Orientated, Connectionless Orientated

What is the MTU size (maximum payload size, in both bytes and KB) for SLIP, PPP, and Ethernet II

a. SLIP: 1006 bytes b. PPP: it's variable. It does have a max, but it is unrealistically large c. Ethernet II: 1500 bytes

What address fields are in an ARP frame and describe the use of each field in Replies?

a. Sender MAC Address 1) Sends its own MAC address to requester b. Sender IP Address 1) Sends its own IP address to requester c. Target Hardware Address 1) Sends reply to requester MAC address d. Target IP Address 1) Sends IP to requester MAC address e. Hardware Type 1) Also ethernet 0x0001 f. Protocol Type 1) Also IP 0x0800 g. MAC Address Length 1) Also 6 bytes h. Protocol Address Length 1) Also 6 bytes i. Operation 1) 2

What address fields are in an ARP frame and describe the use of each field in Requests?

a. Sender MAC Address 1) Sends their own mac address for the return b. Sender IP Address 1) Sends their ip address for the return c. Target Hardware Address 1) Target address is 00-00-00-00-00-00 as it needs to be filled in by replying host d. Target IP Address 1) Has targets IP address that it needs the MAC address from e. Hardware Type 1) Ethernet 0x0001 f. Protocol Type 1) IP 0x0800 g. MAC Address Length 1) 6 bytes h. Protocol Address Length 1) 6 bytes i. Operation 1) 1

What is the purpose and byte size of each header/trailer field in an Ethernet II frame?

a. The Ethernet II frame has an a. 8 byte Preamble and SFD that controls the synchronization between sender and receiver, and defines the frame respectively b. 6 byte destination address c. 6 byte source address d. 2 byte type field that identifies the protocol of sent data e. 45-1500 bytes of data f. And then 4 bytes of Frame check sequence (FCS) that checks for errors

Describe the process of multiplexing and demultiplexing of data by sending and receiving host, respectively.

A sender uses the process of multiplexing, a receiver uses demultiplexing. The sender first uses layer 3 protocols to submit their packets to the network access layer. Then ethernet places a code into Type field in the frame's header to identify the protocol of the packet being sent. The receiver then reads the Type Field to learn which layer 3 protocol's packet is in this frame's payload. Then the ethernet de-encapsulates the packet and submits it to the correct layer 3 protocol for processing

In what order would a sender process TCP/IP layer PDUs?

A sender would first process the Segment(TCP) or Datagram(UDP) PDU, then it would process the Packet PDU, and then they would process the Frame PDU.

A tcp/ip protocol that resolves known logical address (such as IP address) into a physical address (such as a MAC address).

ARP

What protocol takes place in between the Internet and Network Access layers

ARP (Address Resolution Protocol)

List the TCP/IP model in descending order

Application Layer, Transport Layer, Internet Layer, Network Access Layer

A tcp/ip layer that carries out combined functionality of three upper OSI layers, thus providing application interface, formatting of data, encryption, compression, and session management. This layer facilitates services.

Application layer

What three layers in the OSI model make up the Application layer in the TCP/IP model?

Application layer, presentation layer, and session layers

In UNIX terminology, what is a listener process that operates on a server to handle incoming, requests for services

Daemon

What layer is the Datagram PDU a part of?

Depends. If the protocol is IP it is in the Internet layer. If the protocol is UDP then it is being used in the Transport Layer

What are some components that operate at the Network Access Layer?

Ethernet, NIC Drivers, NIC's, PPP protocol, Frames, MAC Addresses, WLAN's

Technologies that are in the Network Access Layer

Ethernet, NIC, NIC Drivers, PPP, Frame, MAC (Physical) Addresses, WLANS

A tcp/ip Application protocol that provides reliable file transfers.

FTP

Technologies that are in the Application Layer

FTP, Telnet, TFTP, HTTP, Services, DNS

What are some important Application Layer Technologies?

FTP, Telnet, TFTP, HTTP, Services, and DNS

A host receiving data may have a data filtering policy that allows the discarding of traffic received by IP Addresses and MAC Addresses. Filtering which one results in a lower processing overhead?

Filtering by MAC source

What is the Data Link Layer PDU?

Frame

A tcp/ip application layer technology that's used for web data transfers.

HTTP

What represents parts of a PDU that are always present in any PDU?

Headers and Payloads

What are the mechanics of address resolution with ARP?

In between the internet and data access layer, an ARP request will broadcast the target IP address on a network to get it to reply back with it's MAC address. All hosts that share the network will process the ARP request when it shouts. The target IP address will unicast, or directly communicate, with the requester.

What is the OSI Network layer called in TCP/IP

Internet Layer

What layer is the IP (logical) address on?

Internet Layer

What are the mechanics of ARP-based duplicate address test?

It is used to verify there is not a duplicate IP address on the network. It will broadcast it's IP address, and if there is a duplicate, it will reply back with the same address and then the initiator will stall it's TCP/IP stack until the issue is resolved.

What is the impact of an ARP cache onto network performance and security?

It saves on dragging internet speeds down by constant ARP requests that every host must process. ARP caches are stored on individual hosts.

In what order would a receiver process PDU's?

It would process Frames, then Packets, and the either Segments or Datagrams depending on if it's TCP or UDP respectively.

The most commonly used type of a physical address (48-bit burned in address that's represented using twelve hexadecimal digits.)

MAC address

What is the minimum and maximum sizes of an Ethernet II frame's payload?

Min/Max Payload(Packet size): 46 bytes-1518 bytes

What is the minimum and maximum overall sizes of an Ethernet II frame?

Min/Max frame size: 64 bytes-1500 bytes b.

What are some components that operate at the Physical Layer?

NIC's, Connectors, Cables

What TCP/IP layer(s) facilitate routers, switches, bridges, hubs, and NICs?

Network Access Layer

What are the OSI Data Link and Physical layers called in TCP/IP

Network Access Layer

What layer is the MAC (physical) address on?

Network Access Layer

A tcp/ip layer that manages access to the medium and facilitates frames,MAC address, network adapters, and drivers.

Network access layer

What is the unit obtained when a protocol-specific header and/or trailer is added to data that came from the layer above

PDU protocol data unit

What is the Internet Layer PDU?

Packet

What are the three headers that allow multiplexing and demultiplexing, and which layer are they a part of?

Packet Headers are associated with the Transport layer, Datagram Headers are associated with the Internet layer, and Data Headers are associated with the network access layer.

Provide order in which a sender of data would process physical addresses, logical addresses, and ports.

Physical Address is processed in layer 1, Network access layer. Logical Address is processed in layer 2, internet layer, Ports are processed in layer 3, transport layer.

What is the order in which a receiver of data would process physical addresses, logical addresses, and ports?

Physical address, logical address, and then ports.

What are broadly used terms for Transport, Internet, and Network Access layer PDUs?

Segment - L4 PDU, i.e. data from above with reliable L4 protocol header added. Datagram - L4 PDU, i.e. data from above with unreliable L4 protocol header added. Packet - L3 PDU, i.e. segment or datagram that came from above with L3 protocol header added. Frame - L2 PDU, i.e. packet that came from above with L2 protocol header/trailer added, final PDU to be sent.

The purpose of a TCP/IP port number is to identify which aspect of a system's operation for incoming and outgoing protocol data?

Sending or receiving application processes

What is the purpose of proxy ARP and what are its mechanics?

Since broadcasts do not go outside their own network, a router will detect when an ARP request is requesting an IP address outside it's network. The router will then provide it's own MAC address for the requester, and then the requester will forward it's frame to the router, where it will then be forwarded to it's target destination. The sending host will then create an entry in it's ARP cache that resolves the IP address with the routers MAC address.

A tcp/ip transport layer protocol that provides reliable transport of data.

TCP

What are some important Transport Layer Technologies?

TCP, UDP, Datagram, Segment, connection-oriented, connectionless-oriented, Ports

What is the OSI Transport layer called in TCP/IP

Transport Layer

A tcp/ip application layer technology that provides lightweight file transfers.

Trivial FTP

A tcp/ip transport layer protocol that provides connectionless transport of data.

UDP

A procedure that breaks large packets into smaller ones in order to match the physical network's capacity.

fragmentation

A name for Network access layer PDU

frame

Main disadvantage of peer communication principle

header overhead

A tcp/ip layer that facilitates the same exact functions as the osi network layer, such as hierarchical logical addresses, routing, and fragmentation

internet layer

The most commonly used type of logical address.

ip address

What function does PPP provide?

it is a modern protocol that encapsulates packets of many types and supports authentication. It supports large packets and requires no fragmentation that originate from ethernet or WLAN segments. Also provides a. Addressing - uses Link Control Protocol (LCP) for dynamic configuration of address and control fields on both ends b. Protocol identification - encapsulates not only IP packets but also AppleTalk, IPv6, IPX and other packet types c. Bit-level integrity - uses the same Frame Check Sequence (FCS) mechanism that Ethernet uses d. Delimitation - separate frames with 0x7E sequence, uses different replacement methods within payload depending on the connection type

What function does Ethernet II provide?

it is a technology that works well with TCP\IP, but is not actually a part of it. It's frame carries IP packets and other packet types in their payload

What function does SLIP provide?

it is an obsolete protocol that provides point-to-point links that transmit IP packets between UNIX hosts. Uses trivial inter-frame delimiters. It provides delimitation by separating packets by the special character "end" at the beginning and end of each packet. Frame size is limited to 1006 bytes due to outdated UNIX drivers.

What is RARP's general use?

it is an obsolete protocol, but before they were able to, workstations were diskless and could not store their own IP address. On boot they would send a broadcast, asking the network for an IP address. The RARP server would then unicast one to them

What is the purpose of using ARP cache, and how does it operate?

it is used so that when a requesting broadcast happens, everything on the network only has to process the request once. When an ARP request is resolved, the requester caches the resolved MAC address so it doesn't have to broadcast again.

A address type that allows for addressing networks as well as uniquely identifying hosts within networks.

logical address.

What is the process of combining multiple outgoing protocol streams at the Transport and Network layers in TCP/IP

multiplexing

A mechanism that allows for multiplexing outbound TCP and UDP dat into packet stream at the sending computer as well as demultiplexing this data at the receiving computer.

protocol numbers

Common name for ports in the range 1024-49151.

registered ports

A network function that implements finding the best path for delivering data.

routing

A name for tcp/ip transport layer PDU's used by connection oriented protocols.

segment

General term for memory-resident listeners that handle incoming requests by launching addition execution threads.

services

A combination of IP address and port that's uniquely identifies an instance of tcp/ip service within a network.

socket

A very old tcp/ip application layer for remote terminal emulation

telnet

What is TCP's general use?

to be a reliable protocol that handles data delivery made by software applications. It then encapsulates the data into segments and passes it on to layer 2

What is IP's general use?

to be a routable protocol that encapsulates data given from the transport layer that carries a source and destination address

What is ARP's general use?

to resolve an IP address with it's physical address by broadcasting a request on a local network the IP address it's looking for. Then the requested IP address replies back with the MAC address that was sought

A tcp/ip layer that accepts and fulfills requests for reliable or unreliable delivery of data by Application layer services. This layer defines and port numbers

transport layer

An Ethernet mechanism that allows for multiplexing outbound L3 data into a frame stream at the sending computer, as well as demultiplexing this data at the receiving computer.

type field

Common name for ports in the range 0-1023.

well known ports