Chapter 30 Flashcards
What is current IP version
4
What is TTL
Time to live. This field is used to prevent a datagram to traveling forever around a path.
What header checksum field do in datagram header
This ensures all fields of header do not contain an error
Does the datagram is completely encapsulated in frame header
Yes
Does the destination address in frame header is hardware address
Yes
Does the destination address in an IP header is an IP address
Yes
When encapsulation done
On transmission, encapsulation done only once. On receiving destination, receiver discard that frame and take out IP datagram and in case it need to be send to next hop encapsulation has to be done again.
What is MTU
A maximum transmission unit (MTU) is the largest size packet or frame, specified in octets (eight-bit bytes), that can be sent in a packet- or frame-based network such as the Internet. The Internet’s Transmission Control Protocol (TCP) uses the MTU to determine the maximum size of each packet in any transmission.
What is fragmentation
Fragmentation is breaking an IP datagram into multiple datagrams. In case a router receives an IP datagram which MTU is greater than next physical network MTU, then it do fragmentation to break it up into multiple.
What is Fragment offset field
Fragment offset field is used when we need to reassemble fragmented pieces into one
What is reassembling
Its a process to reassemble fragmented pieces
Who do fragmentation and who do reassembling
Router do fragmentation and last computer (host) do reassembling
What is identification field
Its a field in IP header, which tells receiving computer which packet belongs to which specific IP datagram.
What is fragment loss
Either we get all fragments or nothing
What is delayed delivery or out of delivery
When receiving computer receives first packet, it starts the timer. All intended packets of same series should come with in time limit of this timer otherwise, all of them will be discarded and this phenomena is called delayed delivery or out of delivery.
