The Network Layer

Question 1

IP Datagram

Answer 1

A highly structured series of fields that are strictly defined. Max size is 16 bits aka 65,535.

Question 2

Version field

Answer 2

States what version of IP is being used. Most common version is IPv4.

4 bits

Question 3

Header Length Field

Answer 3

Declares how long the entire header is.

4 bits
20 bytes is minimum
IPv4 is always 20 bytes

Question 4

Service Type field

Answer 4

These 8 bits can be used to specify details about quality of service tech.

Question 5

Total length field

Answer 5

Indicates the total length of the IP datagram its attached to.

16 bits

Question 6

Identification field

Answer 6

A 16 bit number that’s used to group messages together

Question 7

Flag field

Answer 7

Used to indicate if a datagram is allowed to or if it has already been fragmented

Question 8

Fragmentation

Answer 8

The process of taking a single IP datagram and splitting it up into several smaller datagrams

Question 9

Time to live field
TTL

Answer 9

An 8 bit field that indicates how many router hops a datagram can traverse before it’s thrown away.

Question 10

Protocol field

Answer 10

An 8 bit field that contains data about what transport layer protocol is being used. (TCP/UDP)

Question 11

Header checksum

Answer 11

A checksum of the contents of the entire IP datagram header.

Question 12

IP options field

Answer 12

An optional field and is used to set special characteristics for datagrams primarily used for testing purposes

Question 13

Padding field

Answer 13

Last field of the IP datagram. A series of zeros used to ensure the header is the correct total size.