• Share
  • Email
  • Embed
  • Like
  • Save
  • Private Content

Loading…

Flash Player 9 (or above) is needed to view presentations.
We have detected that you do not have it on your computer. To install it, go here.

Like this presentation? Why not share!

Fragmentation

on

  • 989 views

 

Statistics

Views

Total Views
989
Views on SlideShare
989
Embed Views
0

Actions

Likes
0
Downloads
13
Comments
0

0 Embeds 0

No embeds

Accessibility

Categories

Upload Details

Uploaded via as Microsoft PowerPoint

Usage Rights

© All Rights Reserved

Report content

Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
  • Full Name Full Name Comment goes here.
    Are you sure you want to
    Your message goes here
    Processing…
Post Comment
Edit your comment

    Fragmentation Fragmentation Presentation Transcript

    • FRAGMENTATION
      - An Internetworking concept
      Shashwat Shriparv
      dwivedishashwat@gmail.com
      InfinitySoft
    • What is fragmentation?
      Splitting up things into smaller more manageable entities for incorporating ease in use and flexibility in transport.
      Where could it possibly come in Networks ?
    • Each n/w imposes some maximum size on its packets, the reason being;
      Hardware (frame size)
      Operating System (buffers size 512 bytes)
      Protocols (no. of bits in packet length field)
      Compliance with some standard
      To reduce error-induced retransmission to some level
      Prevent packet from choking channel
    • Problems
      A large packet wants to travel through a network whose maximum packet size is small.
      What if the original source packet is too large to be handled by the destination network?
      Routing algorithms to prevent such situation (not applicable)
    • Fragmentation in networks
      Allow gateways to break up packets into fragments, sending each packet as a separate internet packet
      Breaking up a thing is easy, but fixing it back is not that easy
    • Types of fragmentation
      Transparent
      Non transparent
    • Transparent Fragmentation
      Caused by a “small packet” network transparent to any subsequent networks through which the packet may pass on its way to the destination
      Gateways fragment oversized packets, each addressed to the same exit gateway, where they are recombined
      The process carries on until destination is reached
    • Problems
      Exit gateway should know that it has received all fragments to start combination sequence
      All packets must exit via the same gateway, else data loss occurs
      Overhead required to fragment and reassemble at each gateway
    • Non transparent Fragmentation
      Refrain from recombining fragments at intermediate gateways
      Fragments are considered as packets and are passed through the gateways
      Recombination occurs only at the destination host
      IP follows this methodology
    • Problems
      Requires all hosts to do Reassembly
      Increases overhead, larger the packet, more the headers
      An advantage being multiple exit gateways can be employed increasing the efficiency of the transmission
    • Schemes
      Fragments should be numbered in a way that aids recombination
      Trees can be used
      0 can be split as 0.1, 0.2, 0.3 …..
      These can be again fragmented as 0.0.0, 0.0.1, 0.0.2, …….., 0.1.0, 0.1.1 etc.
      Only if enough space is reserved in header such terminology can be employed
      Sufficient to reorder fragments
    • THANK YOU
      Shashwat Shriparv
      dwivedishashwat@gmail.com
      InfinitySoft