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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 ...


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Rather simple: each direction has its own and independent sequence number and sliding window. So, whether the ends are sending data unidirectionally (one end just ACKing with otherwise empty segments) or bidirectionally doesn't matter.


2

One option is to use an intermediary rendezvous server in the cloud, and all devices connect to it. There are several options for encryption, but we’d need more details before recommending something.


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what happens if segment 50 gets missing along the line? The receiver can either simply wait for retransmission (when the sender's timer for a unACKed segment expires it is resent automatically) send duplicate ACKs (DUPACK) for 50 (the next expected segment) to prompt a faster retransmission The receiver can also selectively ACK (SACK) 51-100 to avoid a ...


1

Problem solved and cause found. The LAG was working fine, and my inkling on burst packet rates was close to the mark. The problem also occurred with only a single link - no LAG. The problem was reproducible on another switch with similar buffer characteristics (Netgear S3300 - which has a 12MB buffer like the Cisco SG500X). Flow control between the server ...


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Yes. An increase in path cost only means that the path may be less preferred than another (or it may be the only path). If the route is still in the routing table, the router will still forward the packet.


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can we still transfer packets between the two routers? Yes. But your network might not work efficiently or at all. Basically, most routing algorithms in practice use Dijkstra's algorithm (OSPF, IS-IS, SPB) which is faster to converge. Any router can only use the information that is has gained access to - effectively, until the network has converged, there's ...


1

That depends on whose definition of socket you use and in some cases whether the packet is opening a new connection or transferring data for an existing connction. The RFC that defines TCP defines the term socket as a combination of an IP address and a port. By this definition the two packets have the same socket on the server side but different sockets on ...


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