2010年10月10日 · The prefix-length in IPv6 is the equivalent of the subnet mask in IPv4. However, rather than being expressed in four octets like it is in IPv4, it is expressed as an integer between 1 through 128. For example: 2001:db8:abcd:0012::0/64 specifies a subnet with a range of IP addresses from: 2001:db8:abcd:0012: 0000:0000:0000:0000 - 2001:db8:abcd ...

This is variously called the network mask length or prefix length, and it is represented as a / followed by the number of consecutive 1 bits in the network mask. Counting the number of consecutive 1 bits in the example totals 21, which can be represented as /21. Given a mask length, you can calculate the dotted-decimal representation of the mask.

2016年10月20日 · A subnet mask is a 32 bit value that allows the device that's receiving ip packets to distinguish the network ID portion of the IP address from the host ID portion of the IP address, so without a subnet mask that can be represented in form of a 32 value like (255.0.0.0) or slash-notation (/8) it is impossible to identify the network prefix of ...

prefix-length is a decimal value specifying how many of the leftmost contiguous bits of the address comprise the prefix. For example, the following are legal representations of the 60-bit prefix 12AB00000000CD3 (hexadecimal): 12AB:0000:0000:CD30:0000:0000:0000:0000/60 12AB::CD30:0:0:0:0/60 12AB:0:0:CD30::/60

2024年12月21日 · Using a subnet prefix length other than a /64 will break many features of IPv6, including Neighbor Discovery (ND), Secure Neighbor Discovery (SEND) , privacy extensions , parts of Mobile IPv6 , Protocol Independent Multicast - Sparse Mode (PIM-SM) with Embedded-RP , and Site Multihoming by IPv6 Intermediation (SHIM6) , among others. A number of ...

Using a subnet prefix length other than a /64 will break many features of IPv6, including Neighbor Discovery (ND), Secure Neighbor Discovery (SEND) , privacy extensions , parts of Mobile IPv6 , Protocol Independent Multicast - Sparse Mode (PIM-SM) with Embedded-RP , and Site Multihoming by IPv6 Intermediation (SHIM6) , among others. A number of ...

2021年10月6日 · Default subnet masks: Class A: 255.0.0.0 (prefix length : 8) Class B: 255.255.0.0 (prefix length : 16) Class C: 255.255.255.0 (prefix length : 24) This p appears to me like, if a network administrator uses Class C address, then, he will be limited to have maximum of 254 hosts (excluding 0 and 255), whereas, if he chooses Class A address, then ...

2016年11月25日 · The prefix length denotes the number of leftmost bits set to 1 in the mask, so a prefix length of 24 denotes a mask of 255.255.255.0. Prefix lengths are contiguous and there is no way to specify a non-contiguous mask. Some routing protocols such as BGP use prefix length (and not mask) within the updates, so there is no way to even advertise a ...

Your last question could make sense if you reverse it to ask how many /64 networks can be made from a /30 prefix. The way to calculate that is to subtract 30 from 64 to get 34. The answer would be 2 to the power of the result. 64 - 30 = 34 2^34 = 17,179,869,184 That means you can derive 17,179,869,184 /64 networks from one /30 prefix.

2014年7月11日 · Yes, but most importantly, classful addressing (i.e. fixed length subnet masks) is obsolete and has been for at least 20 years. I don't know why networking classes still teach it. There are many, many resources on this and other stack exchanges (as well as the Internet) that explain how to use variable length masks.