What situations are the IP packets fragmented under?

[guominquan]

Hello,everyong

I am reading ACL applied to IP packets fragmented.But I am bit confused to IP packets fragments. What situations are the IP packets fragmented under?Any help I shall be appreciated!

Regards!

Minquan

[Jon Marshall]

Hi Minquan

packets are usually fragmented when the MTU (maximum transmission unit) of the network segment is smaller than the actual packet size.

When this happens the router that connects the two network segments will fragment the IP packet before transmitting the packet on to it's destination. The packets will then continue to their destination before they are reassembled into the original packet.

HTH

[amit-singh]

In addition to Jon's reply whenever a router fragments the packet based on the interface MTU, it adds a pointer to the fragmented packet to let the far end know that this packet is a fragmented one and it should wait for the remaining portion of the packet and then re-assemble.

HTH,

-amit singh

[smothuku]

Hi Minquan ,

The below link may help you.

http://www.cisco.com/en/US/tech/tk827/tk369/technologies_white_paper09186a00800949b8.shtml

Thanks,

satish

[guominquan]

Thanks,Friends!

These are very useful for me!

Regards!

Minquan