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(e) Benefits of subnetting the network (v) Enhanced security
(i) Efficient IP address management
(ii) Reduces the wastage of IP (vi) Segments the network into
addresses and allows better smaller subnets, making it Chapter Three: Advanced Computer Networks
utilization of the available easier to manage and secure each
FOR ONLINE READING ONLY
address space. segment individually.
(iii) Improved network performance (vii) Simplified troubleshooting
(iv) Limits the size of broadcast
domains, reducing network Easier to identify and isolate network
traffic and collisions. issues within smaller subnetworks.

Internet protocol version 6 (IPV6)
One of the primary motivations behind the development of IPv6 was to increase
the IP address pool. IPv6 uses a 128-bit address, which allows for a maximum
of 2 addresses, or 340,282,366,920,938,463,463,374,607,431,768,211,456
128
addresses—enough to assign multiple IP addresses to every grain of sand on Earth.
Consequently, the traditional 32-bit IPv4 dotted-quads are no longer sufficient. IPv6
addresses are formatted into eight 16-bit hexadecimal blocks, separated by colons.
These addresses are not only longer but also include both numbers and letters. At
first glance, IPv6 addresses, such as 2001:0db8:3c4d:0015:0000:0000:abcd:ef12,
may look like an impenetrable secret code.

(a) IPv6 address types
IPv6 does not utilise classes. Instead, it supports the following three types of IP
addresses: Unicast, multicast, and anycast.

In IPv6, unicast and multicast messaging function in the same way as they do in
IPv4. However, IPv6 does not support broadcast; instead, it achieves similar results
using its multicast mechanism. Multicast addresses in IPv6 begin with ‘FF’ (255),
similar to IPv4 addresses. Anycast in IPv6 is a variation of multicast: while multicast
sends messages to all nodes within the multicast group, anycast sends messages to
any one node in the group. Anycast is an advanced networking technique designed
to meet the application's failover and load balancing requirements.

(b) IPv6 header format
In addition to the expanded address space, IPv6 introduces several enhancements,
including changes to the header format as shown in Figure 3.19.

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Student’s Book Form Five

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