3com S7906E Manuel De Montage

 

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IPv6 uses IPsec as its standard extension header to provide end-to-end security. This feature provides 

a standard for network security solutions and enhances the interoperability between different IPv6 

applications. 

The Flow Label field in the IPv6 header allows the device to label packets of a flow and provide special 

handling for these packets. 

The IPv6 neighbor discovery protocol is implemented through a group of Internet Control Message 

Protocol Version 6 (ICMPv6) messages that manage the information exchange between neighbor 

nodes on the same link. The group of ICMPv6 messages takes the place of Address Resolution 

Protocol (ARP) messages, Internet Control Message Protocol version 4 (ICMPv4) router discovery 

messages, and ICMPv4 redirection messages and provides a series of other functions. 

IPv6 cancels the Options field in the IPv4 header but introduces multiple extension headers to provide 

scalability while improving efficiency. The Options field contains 40 bytes at most, while the size of IPv6 

extension headers is restricted to the maximum size of IPv6 packets. 

An IPv6 address is represented as a set of 16-bit hexadecimals, separated by colons. An IPv6 address 

is divided into eight groups, and the 16 bits of each group are represented by four hexadecimal 

numbers, for example, 2001:0000:130F:0000:0000:09C0:876A:130B. 

To simplify the representation of IPv6 addresses, zeros in IPv6 addresses can be handled as follows: 

z 

Leading zeros in each group can be removed. For example, the above-mentioned address can be 

represented in a shorter format as 2001:0:130F:0:0:9C0:876A:130B. 

z 

If an IPv6 address contains two or more consecutive groups of zeros, they can be replaced by a 

double-colon ::. For example, the above-mentioned address can be represented in the shortest 

format as 2001:0:130F::9C0:876A:130B. 

 

A double-colon can be used only once in an IPv6 address. Otherwise, the device is unable to determine 

how many zeros that double-colons represent when converting them to zeros to restore a 128-bit IPv6 

address. 

 

An IPv6 address consists of two parts: address prefix and interface ID. The address prefix and the 

interface ID are respectively equivalent to the network ID and the host ID in an IPv4 address.