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28

Fragmentation is resource intensive in a router, and it slows packet forwarding. Today, we use PMTUD to determine the smallest MTU in the path so that packets are properly sized prior to sending. There are also fragmentation attacks, so many businesses drop fragments. What you are confusing is something like TCP segmentation, which is very different than ...


8

IP packet level fragmentation occurs when the transmitting side is not properly aware of the MTU of the path. This results in worse performance than if the packets are sized correctly already at the endpoint. For example, if the transmitting side of a TCP connection believes the path MTU to be 1500 bytes, it will send packets of that size. If the real path ...


5

IP fragmentation can cause excessive retransmission at the TCP level. TCP transmits information as a series of segments, and these are the units of acknowledgement and retransmission as well. If a TCP segment is lost in the network, the entire segment has to be retransmitted. If IP fragmentation occurs, the segment will be split into multiple fragments. The ...


3

RFC 1918 provides address ranges that you can safely use within a private network without any danger that these same addresses might be used on the public Internet. Any node within your network needs to be able to address any destination it requires. If your local network uses the same address range (subnet) that some public servers do (e.g 244.18.42.0/24), ...


3

That's sloppy writing in the instructions, but I'm pretty sure it means you should use /24 networks (i.e. 172.16.0.0/24, 172.16.1.0/24, 172.16.2.0/24, etc). It would've been better to say to use class-C-sized networks, but even that's obsolete terminology since network classes haven't been a thing since 1993.


3

On the Internet, only public addresses can be used. RFC 1918 reserved address ranges that can be used within private networks. By convention, these addresses are not routed across the Internet. Inside your private network, both public and your private addresses can be used, in any combination. A packet with private source and public destination is bound to ...


1

Why do we need private addresses such as RFC1918? Well, say for instance you configure your local network with your router interface 8.8.8.1/24. You configure your clients with DHCP of range 8.8.8.100-8.8.8.254. Everything will work fine, your clients in your local network will be able to contact each other. You can even S-NAT these addresses to your WAN-...


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