因此无法像IPv6一样将next header=59表示没有下一个协议头。在IPv4中，如果没有下一个协议头，则协议...
IPv6和IPv4相比,去除了IHL、identifiers、Flags、Fragment Offset、Protocol、Header Checksum、 Options、Paddiing,新增了Flow Label和Next Header,而且理论上这Next Header可以无限扩展; IPv4中的Header Checksum被去掉了,是因为IPv4经过每个路由器都要改变TTL,意味着每个路由器都要重新计算这个值,这会大大的降低效率,由于...
这也是header中的三个字段identification,flag和fragmentation offset的作用。 4.3.3 IPv4 Addressing 每个IP 地址都是 32 bit,因此一共有约 4 亿个 IP 地址。这些地址都被分为 4 段,每段 1 字节(8 bit),用.隔开。例如193.32.216.9,每个数字都是 10 进制。 Interface addresses and subnets 如图所示,223.1.1...
IPv4 and IPv6 packets are like envelopes that carry data across the internet. Just like envelopes, they have a header that contains important information for delivery. However, IPv4 and IPv6 have different header designs: IPv4 headers are like envelopes with variable sizes. They have 12 fields ...
IPv4 and IPv6 Functionality • IPv6 for Cisco IOS XR Software • Larger IPv6 Address Space • IPv6 Address Formats • IPv6 Address Type: Unicast • IPv6 Address Type: Multicast • Simplified IPv6 Packet Header • Path MTU Discovery for IPv6 ...
IPv4地址的网络号字段用来唯一的标识一个网段,或者若干网段的聚合。IP地址与子网掩码转换为二进制,进行AND计算后的结果即为网络号字段。 IPv4地址的主机号字段用来唯一的标识同一网段内的具体某台网络设备。IP地址与子网掩码转换为二进制,再将子网掩码取反,进行AND计算后的结果即为主机号字段。
It allows a limitless number of IP addresses. Type of addresses Unicast, multicast, broadcast Unicast, multicast, and anycast Number of header fields 12 8 Length of header filed 20 40 Checksum fields Has checksum fields Has no checksum fields Packet size The minimum packet size for an IPv4 is...
The main difference between IPv4 and IPv6 is the address size of IP addresses. The IPv4 is a 32-bit address, whereas IPv6 is a 128-bit hexadecimal address. IPv6 provides a large address space, and it contains a simple header as compared to IPv4. It provides transition strategies that ...
On the border device, the IPv4/IPv6 dual protocol stack is enabled, and an IPv6 over IPv4 tunnel is configured. After the border device receives a packet from the IPv6 network, the device appends an IPv4 header to the IPv6 packet to encapsulate the IPv6 packet as an IPv4 packet if th...
sum = Checksum(0, (VOID *)pIpHeader, ipHeadLen);对整个ip包头的累加pIpHeader->chksum = HTONS((UINT16)(~sum));结果为计算值的反码,(别忘转化为网络字节序)2、ipv6包头在ipv6中已经省略了checksum部分,但在后面的部分要有的,比如TCP/UDP包,别高兴的太早...