How do ports work with IPv6?

2019-01-22 05:15发布

问题:

Conventional IPv4 dotted quad notation separates the address from the port with a colon, as in this example of a webserver on the loopback interface:

127.0.0.1:80

but with IPv6 notation the address itself can contain colons. For example, this is the short form of the loopback address:

::1

How are ports (or their functional equivalent) expressed in a textual representation of an IPv6 address/port endpoint?

回答1:

They work almost the same as today. However, be sure you include [] around your IP.

For example : http://[1fff:0:a88:85a3::ac1f]:8001/index.html

Wikipedia has a pretty good article about IPv6: http://en.wikipedia.org/wiki/IPv6#Addressing



回答2:

The protocols used in IPv6 are the same as the protocols in IPv4. The only thing that changed between the two versions is the addressing scheme, DHCP [DHCPv6] and ICMP [ICMPv6]. So basically, anything TCP/UDP related, including the port range (0-65535) remains unchanged.

Edit: Port 0 is a reserved port in TCP but it does exist. See RFC793



回答3:

Wikipedia points out that the syntax of an IPv6 address includes colons and has a short form preventing fixed-length parsing, and therefore you have to delimit the address portion with []. This completely avoids the odd parsing errors.

(Taken from an edit Peter Wone made to the original question.)



回答4:

They're the same, aren't they? Now I'm losing confidence in myself but I really thought IPv6 was just an addressing change. TCP and UDP are still addressed as they are under IPv4.



回答5:

I'm pretty certain that ports only have a part in tcp and udp. So it's exactly the same even if you use a new IP protocol



回答6:

I would say the best reference is Format for Literal IPv6 Addresses in URL's where usage of [] is defined.

Also, if it is for programming and code, specifically Java, I would suggest this readsClass for Inet6Address java/net/URL definition where usage of Inet4 address in Inet6 connotation and other cases are presented in details. For my case, IPv4-mapped address Of the form::ffff:w.x.y.z, for IPv6 address is used to represent an IPv4 address also solved my problem. It allows the native program to use the same address data structure and also the same socket when communicating with both IPv4 and IPv6 nodes. This is the case on Amazon cloud Linux boxes default setup.



回答7:

I am not sure what you are getting at. The TCP and UDP layer is the same structure. IPV6 as the name implies is about the IP layer being enhanced not the TCP or UDP layers.



标签: tcp udp ipv6 ports