Packets And Jumbo Frames

Question 1

packet

Answer 1

frame/block/cell
used to send data around network
varying # of packets = full data from application
broken down further if necessary
packets vary depending on protocol

Question 2

frame composition

Answer 2

frame header
frame/user data
preamble
FCS

Question 3

frame header

Answer 3

contains destination/source mac address and type/length

type/length: defines packet type

Question 4

frame/user data

Answer 4

min picket size = 64 bytes (max 1500)

pad with 0s to reach min

Question 5

preamble

Answer 5

sync and frame beginning

Question 6

fcs

Answer 6

frame checking sequence

error checking, crc

Question 7

ethernet frame reception

Answer 7

receive frame: my mac address?
no? discard
yes? frame to small (<64 bytes)?
yes? discard
no? crc ok?
no? discard
yes? frame < 1518 byes?
no? discard
yes? process data

Question 8

Ethernet frame advantages

Answer 8

universally accepted
support any type of package
process completed at layer 2 (data), protocol independent

Question 9

Ethernet frame disadvantages

Answer 9

low data load support
increased issues with adding more data
increased processing/packets

Question 10

Ethernet Jumbo Frames

Answer 10

1500-9000 bytes
used for gigabit and high speed networks
vendor dependent, supported by most networks
how? crc calculations done by later 1 (network card)

Question 11

Jumbo frame types

Answer 11

baby giant (1998), multiple lang switching
mini jumbo (2500), fiber
giant frame (9000)

Question 12

jumbo frame advantages

Answer 12

decrease # of frames

decreased processing

Question 13

jumbo frame disadvantages

Answer 13

data load limited by lowest common denominator
network equipment must support crc check change
lack of standard data size
increased transmission time