Guy Harris wrote:
Not true of the IP header size - the IPv4 header has a *minimum* length of 20 bytes, but if there are IP options, it could be longer than 20 bytes. The first byte of the IP header is the version/length byte; it includes a length, in units of 4-byte words (so that a value of 0x45 means "version 5, 5 4-byte words long").
Sorry, that should be "version 4, 5 4-byte words long". - This is the tcpdump-workers list. Visit https://lists.sandelman.ca/ to unsubscribe.
