How do routers. switches, bridges and hubs deal with corrupted data? By data corruption I mean frame/packet corruption, we can stick to the corruption due to a collision for simplicity. I know that switches can detect frame corruption if they are not set to cut-through forwarding. But are they always doing it ? And how does a switch detect a corruption? I assume it is done by checking CRC but confirmation would be appreciated. I have read that similar mechanisms ( _cut-through_ and _store-and-forward_ ) can be found in routers. So do routers detect packet corruption in the same way as switches do ? And does working in layer 3 have any impact on this process ? Finally hubs. Can they detect any data corruption or are they always forwarding data without any checks ? Wiki says [1] that _store and forward_ method is typically used on bridges and points out that frame integrity is verified so I take it for granted. [1] <

Ethernet interfaces on hosts, switches, routers, etc. will detect corrupted frames and drop them.

Routers will also look at the IPv4 Header Checksum (IPv6 does not have this) to see if a packet header is corrupt, and drop the packet if it is.

Hosts will look at the transport protocol to see if it is corrupt for those transport protocols that have a checksum, and they will drop those corrupt datagrams.

Hubs, on the other hand, simply repeat any received signals out the other interfaces, so there is no detection of corruption. Think of a hub as a powered cable.