|
 Internet
The
Internet is an outgrowth of a network established in 1960s to meet the
needs of reaserchers working in the defense industry in the USA. That was
called the ARPANET. Many people have helped in the development of
internet. The initial phase in the develpment of internet began way back
in 50s. In order too regain the space supremacy from USSR (which they
stole from US by launching sputnik in 1957), the US government created an
agency called ARPA (Advanced Reaserch Projects Agency), with J.C.R
Licklider as the head of computer department.
Today's
computer cummunication networks are based on a technology called packet
switching. This technology, which arose from DARPA - sponsored reseach in
the 1960s, is fundamentaly different from the technology that was then
employed by the telephone system (which based on "circuit
switching") or by the military messaging system(which was based on
"message switching").
These
efforts came together in 1977 when a four-network demonstration was
connducted linnkinng ARPANET, SATNNET, Ethernet and PRNET. The sattelite
effort, in particular, drew international involvement from
partcipants in the UK, Norway, and later Italy and Germany.
The
name "Internet" refers to the global seamless interconnection of
networks made possible by the protocols devised in the 1970s through
DARPA-sponsored research, the innternet protocols, still inn use today.
YEAR
BY YEAR
1962:
RAND
Paul Baron, of the RAND Corporation (a government agency), was
commissioned by the U.S. Air Force to do a study on how it could maintain
its command and control over its missiles and bombers, after a nuclear
attack. This was to be a military research network that could survive a
nuclear strike, decentralized so that if any locations (cities) in the
U.S. were attacked, the military could still have control of nuclear arms
for a counter attack. Baran's finished document described several ways to
accomplish this. His final proposal was a packet switched network.
"Packet
switching is the breaking down of data into data grams or packets that are
labeled to indicate the origin and the destination of the information and
the forwarding of these packets from one computer to another computer
until the information arrives at its final destination computer. This was
crucial to the realization of a computer network. If packets are lost at
any given point, the message can be resent by the originator".
Back
bones: None - Hosts: None
1968:
ARPA
awarded the ARPANET contract to BBN. BBN had selected a Honeywell
minicomputer as the base on which they would build the switch. The
physical network was constructed in 1969, linking four nodes: University
of California at Los Angeles, SRI (in Stanford), University of California
at Santa Barbara, and University of Utah. The network was wired together
via 50 Kbps circuits.
Backbones:
50Kbps ARPANET - Hosts: 4
1972:
The
first e-mail program was created by ray Tomlison of BBN. The Advanced
Research Projects Agency (ARPA) was renamed.
The Defense Advanced Research Projects Agency (or DARPA).ARPANET was
currently using the Network Control Protocol or NCP to transfer data. This
allowed communications between hosts running on the same network.
Backbones:
50Kbps ARPANET-Hosts: 23
1973:
Development
began on the protocol later to be called TCP/IP, a group headed by Vinton
Cerf from Stanford and Bob Kahn from DARPA developed it. This new protocol
was to allow diverse computer networks to interconnect and communicate
with each other.
Backbones:
50Kbps ARPANET-Hosts: 23+
1974:
First
use of term Internet by Vint Cerf and Bob Kahn in paper on Transmission
Control Protocol.
Backbones: 50Kbps ARPANET-Hosts: 23+
1975:
The
USSR launches Sputnik, the first artificial earth satellite. In response,
the United States forms the Advanced Research Projects Agency (ARPA)
within the Department of Defense (DoD) to establish US lead in science and
technology applicable to the military.
Backbones:
None - Hosts: None
1976:
Dr.
Robert M. Metcalfe develops Ethernet, which allowed coaxial cable to move
data extremely fast. This was a crucial component to the development of
LANs. The packet satellite project went into practical use. SATNET,
Atlantic Packet Satellite network, was born. This network linked the
United States with Europe. Surprisingly, it used INTELSAT satellites that
were owned by a consortium of countries and not exclusively the United
States Government.UUCP (Unix-to-Unix Copy) developed at AT&T Bell Labs
and distributed with UNIX one year later.
The
Department of Defense began to experiment with the TCP/IP protocol and
soon decided to require it for use on ARPANET.
Backbones:
50Kbps ARPANET, plus satellite and radio connections-Hosts: 111+
1979:
USENET
(the decentralized news group network) was created by Steve Bellovin, a
graduate student at University of North Carolina, and programmers Tom
Truscott and Jim Elis. It was based on UUCP.
The
Creations BITNET, by IBM, "Because its Time Network", introduced
the "store and forward" network. It was used for email and
listservs.
Backbones:
50Kbps ARPANET, plus satellite and radio connections-Hosts:111+
1981:
National
Science Foundation crated backbone called CSNET 56Kbps network for
institutions without access to ARPANET. Vinton Cerf proposed a plan for an
inter-network connection between CSNET and the ARPANET.
Backbones:
50Kbps ARPANET, 56Kbps CSNET, plus satellite and radio connection-Hosts:
213
1983:
Internet
Activities Board (IAB) was created in 1983. On January 1st, every machine
connected to ARPANET had to use TCP/IP. TCP/IP became the core Internet
protocol and replaced NCP entirely.
The
University of Wisconsin created Domain Name System (DNS). This allowed
packets to be directed to a domain name that would be
translated
by the server database into the corresponding IP number. This made it much
easier for people to access other servers, because they no longer had to
remember numbers.
Backbones:
50Kbps ARPANET, 56Kbps CSNET, plus satellite and radio connections -
Hosts: 562
1984:
The
National Science Foundation began deploying its new T1 lines, which would
finish by 1988.
Backbones:
50Kbps ARPANET, 56Kbps CSNET, 1.544Mbps (T1) NSFNET, plus satellite and
radio connections - Hosts 1961
1986:
The
Internet Engineering Task Force or IET was created to serve as a forum for
technical co-ordination by contractors for DARPA working on ARPANET, US
Defense Data Network (DDN), and the Internet core gateway system.
Backbones:
50Kbps ARPANET, 56Kbps CSNET, 1.544Mbps (T1) NSFNET, plus satellite and
radio connections - Host: 2308
1987:
BITNET
and CSNET merged to form the Corporation for Research and Educational
Networking (CREN), another work of the National Science Foundation.
Backbones:
50Kbps ARPANET, 56Kbps CSNET, 1.544Mbps (T1) NSFNET, plus satellite and
radio connections - Host: 28,174
1988:
Soon
after the completion of the T1 NSFNET backbone, traffic increased so
quickly that plans immediately began on upgrading the network again.
Merit
and its partners formed a not for profit corporation called ANS, Advanced
Network Systems, which was to conduct research into high speed networking.
It soon came up with the concept of th3 T3, a 45 Mbps line. NSF quickly
adopted the new network and the end of 1991 connected all of its sites by
this new backbone.
Backbones:
50Kbps ARPANET, 56Kbps CSNET, 1.544Mbps (T1) NSFNET, plus satellite and
radio connections - Host: 56000
1990:
While
the T3 lines were being constructed he Department of Defense disbanded the
ARPANET and it was replaced by the NSFNET backbone. The original 05Kbs
lines or ARPANET were taken out of service.
Tim
Berners-Lee and CERN in Geneva implement a hypertext system to provide
efficient information access to the members of the international
high-energy physics community.
Backbones:
56Kbps CSNET, 1.544Mbps (T1) NSFNET, plus satellite and radio connections
- Host: 313,000
1991:
CSNET
(which consisted of 56Kbps lines) was discontinued having fulfilled its
important early role in the provision of academic networking service. A
key feature of CREN is that its operational costs are fully met through
dues paid by its member organizations.
The
NSF established a new network, named NREN, the National Research and
Education Network. The purpose of this network is to conduct high speed
networking research. It was it to be used to send a lot of the data that
the Internet now transfers.
Backbones:
Partial 45Mbps (T3) NSFNET, a few private backbones, plus satellite and
radio connections - Host: 617,000
1992:
Internet
Society is chartered.
World-Wide Web released by CERN.
NSFNET backbone upgraded to T3 (44.736Mbps)
Backbones:
45Mbps (T3) NSFNET, private interconnected backbones consisting mainly of
56Kbps, 1.544Mbps, plus satellite and radio connections - Host: 1,136,000
1993:
InterNIC
created by NSF to provide specific Internet services: directory and
database services (by AT&T), registration service (by Network
Solutions Inc.), and information services (by General Atomics/CERFnet).
Marc
Andreessen and NCS and the University of Illinois develop a graphical user
interface to the WWW, called "Mosaic for X".
Backbones:
45Mbps (T3) NSFNET, private interconnected backbones consisting mainly of
56Kbps, 1.544Mbps, and 45Mbs lines, plus satellite and radio connections -
Host: 2,056,000
1994:
No
major changes were made to the physical network. The most significant
thing that happened was the growth. Many new networks were added to the
NSF backbone. Hundreds of thousands of new hosts were added to the
INTERNET during this time period.
Pizza
Hut offers pizza ordering on its Web page. First Virtual, the first
cyberbank, opens.
ATM
(Asynchronous Transmission Mode, 145Mbps) backbone is installed on NSFNET.
Backbones:
145Mbps (ATM) NSFNET, private interconnected backbones consisting mainly
of 56Kbps, 1.544Mbps, and 45Mbs lines, plus satellite and radio
connections - Host: 3,864,000
1995:
The
National Science Foundation announced that as of April 30, 1995 it would
no longer allow direct access to the NSF backbone. The National Science
Foundation contracted with four companies that would be providers of
access to the NSF backbone (Merit). These companies would then sell
connections to groups, organizations, and companies.
$50
annual fee is imposed on domains, excluding .edu and .gov domains that are
still funded by the National Science Foundation.
Backbones:
145Mbps (ATM) NSFNET (now private), private interconnected backbones
consisting mainly of 56Kbps, 1.544Mbps, and 45Mbs lines in construction,
plus satellite and radio connections - Host: 6,642,000
1996
Most
Internet traffic is carried by backbones of independent ISPs, including
MCI, AT&T, Sprint, Uunet, BBN planet, ANS, and more.
Currently the Internet Society, the group that controls the INTERNET, is
trying to figure out new TCP/IP to be able to have billions of addresses,
rather than the limited system of today. The problem that has arisen is
that it is not known how both the old and the new addressing systems will
be able to work at the assume time during a transition period.
Backbones:
145Mbps (ATM) NSFNET (now private), private interconnected backbones
consisting mainly of 56Kbps, 1.544Mbps, 45Mbs, and 155Mbps lines, plus
satellite and radio connections - Host: over 15,000,000 and growing
rapidly
The
ISP that you use might depend on your local area. This site doesn't
recommend any particular service because they all provide one basic
function-connecting you to the rest of the world. Each ISP is unique
because each has slightly different format. You might try several before
settling on one. Some services, such as AT&T Worldnet and America
Online, offer trial memberships in which you can "try before you
buy". Software used on the physical computer to make it a server that
can speak the protocols of the Internet and respond accordingly is called
Internet server software. The particular Internet server software
manufactured by Microsoft is Internet Information Server (IIS).
For
a client computer to be able to communicate with a server on the Internet,
it must have a connection to the Internet. Then, when connected, it must
have a way to contact and receive data from Internet servers through the
various protocols. The connection is accomplished via an Internet service
provider (ISP), such as America Online, CompuServe, MSN, AT&T
Worldnet, MCI, or Sprint. The tool to communicate to the server and
decipher the data returned by the Internet server is handled by the
Internet browser, such as Microsoft's Internet Explorer or Netscape
Navigator.
Where
does Visual Basic fit in all this? Microsoft has positioned Visual Basic
to play an important role on the client side and the server side. On the
client side, you can use a derivative of Visual Basic, VBScript, to create
West page programs that can run from within Internet Explorer. You also
can use Visual Basic to create custom ActiveX components that you can
embed in Web pages and run as any custom ActiveX component would.
NETWORK
PROTOCOLS:-
Protocols
are the agreed-upon ways in which computers exchange information.
Computers need to communicate at many levels and in many different ways,
so there are many corresponding network protocols. Select the appropriate
network and transport protocol or protocols for various token-ring and
Ethernet networks. Protocol choices include:
" DLC
" Apple Talk
" IPX
" TCP/IP
" NFS
" SMB
There are protocols at various levels in the OSI mode. In fact, it is the
protocols at a level in the OSI model that provide the functionality of
that level. Protocols that work together to provide a layer or layers of
the OSI model are known as a protocol stack, or suite.
A
protocol is a set of basic steps that both parties (or computers) must
perform in the right order. For instance, for one computer to send a
message to another computer, the first computer must perform the following
steps. (This is a general example; the actual steps are much more
detailed.)
1.
Break the data into small sections called packets.
2. Add addressing information to the packets identifying the destination
computer.
3. Deliver the data to the network card for transmission over the network.
The receiving computer must perform the same steps, but in reverse Order.
1. Accept the data from the network adapter card.
2. Remove the transmitting information that was added by the
transmitting computer.
3. Reassemble the packets of data into the original message.
Each
computer needs to perform the same steps the same way so that the data
will arrive and reassemble properly. If one computer uses a protocol with
different steps or even the same steps with different parameters (such as
different sequencing, timing, or error correction), the tow computers will
not be able to communicate with each other
OSI,
short for Open Systems Interconnection, is an international standard that
defines seven layers of protocols for worldwide computer communication.
The
application layer is the topmost layer of the OSI model, and it provides
services that directly support user application, such as database access,
e-mail, and file transfers. It also allows applications to communicate
with applications on other computers as though they were on the same
computer. When a programmer writes an application program that uses
network services, this is the layer application program will access.
The
presentation layer translates data between the formats the network
requires and the formats the computer expects. The presentation layer does
protocol conversion, data translates, compression and encryption,
character set conversion, and the interpretation of graphics commands.
The
session layer allows applications on separate computers to share a
connection called a session. This layer provides services such as name
lookup and security to allow two programs to find each other and establish
the communications link. The session layer also provides for data
synchronization and check pointing so that in the event of a network
failure, only the data sent after the point of failure need be re-sent.
The
layer also controls the dialog between two processes, determining who can
transmit and who can receive at what point during the communication.
The
transport layer ensures that packets are delivered error free, in
sequence, and with no losses or duplications. The transport layer breaks
large messages from the session layer (which we'll look at next) into
packets to be sent to the destination computer and reassembles packets
into messages to be presented to the session layer. The transport layer
typically sends an acknowledgement to the originator for messages
received.
The
network layer makes routing decision and forwards packets for devices that
are farther away than a single link. (A link connects two network devices
and is implemented by the data link layer. Two devices connected by a link
communicate directly with each other and not through a third device.) In
larger networks there may be intermediate systems between any two end
systems, and the network layer makes it possible for the transport layer
and layers above it to send packets without being concerned about whether
the end system is immediately adjacent or several hops away.
The network layer translates logical network addresses into physical
machine addresses (the numbers used as destination Ids in the physical
network cards). This layer also determines the quality of service (such as
the priority of the message) and the route a message will take if there
are several ways a message can get to its destination. The network layer
also may break large packets into smaller chunks if the packet is larger
than the largest data frame the data link layer will accept. The network
reassembles the chunks into packets at the receiving end.
The
data link layer provides for the flow of data over a single link from one
device to another. It accepts packets from the network layer and packages
the information into data units called frames to be presented to the
physical layer for transmission. The data link layer adds control
information, such as frame type, routing, and segmentation information, to
the data being sent.
This layer provides for the error-free transfer of frames from one
computer to another. A Cyclic Redundancy Check (CRC) added to the data
frame can detect damaged frames, and the data link layer in the receiving
computer can request that the information be present. The data link layer
can
also detect when frames are lost and request that those frames be sent
again.
The
physical layer is simply responsible for sending bits (bits are the binary
1's and 0' of digital communication from one computer to another. The
physical layer is not concerned with the meaning of the bits; instead it
deals with the physical connection to the network and with transmission
and reception of signals.
This
level defines physical and electrical details, such as what will represent
a 1 or a 0, how many pins a network connector will have, how data will b e
synchronized, and when the network adapter may or may not transmit the
data.
TCP/IP
is short for Transmission Control Protocol / Internet
Protocol. TCP and IP were developed by a Department of Defense
(DOD) research project to connect a number different networks designed by
different vendors into a network of networks (the "Internet").
It was initially successful because it delivered a few basic services that
everyone needs (file transfer, electronic mail, remote logon) across a
very large number of client and server systems. Several computers in a
small department can use TCP/IP (along with other protocols) on a single
LAN. The IP component provides routing from the department to the
enterprise network, then to regional networks, and finally to the global
Internet. On the battlefield a communications network will sustain damage,
so the DOD designed TCP/IP to be robust and automatically recover from any
node or phone line failure. This design allows the construction of very
large networks with less central management. However, because of the
automatic recovery, network problems can go undiagnosed and uncorrected
for long periods of time.
As with all other communications protocol, TCP/IP is composed of layers
In an effort to cut the costs of development, the Advanced
Research Projects Agency (ARPA) of the Department of Defense (DOD) began
coordinating the development of a vendor-independent network to tie major
research sites together. The logic behind this was clear. The cost and
time to develop an application on one system was too much for each site to
re-write
the
application on different systems. Since each facility used different
computers with proprietary networking technology, the need for a
vendor-independent network was the first priority. In 1968, work began on
a private packet-switched network.
In
the early 1970's, authority of the project was transferred to the Defense
Advanced Research Projects Agency (DARPA). Although the original ARPAnet
protocols were written for use with the ARPA packet-switched network, they
were also designed to be usable on other networks as well. In 1981, DARPA
switched their focus to the TCP/IP protocol suite, placing it into the
public domain for implementation by private vendors. Shortly thereafter,
TCP/IP was adopted by the University of California at Berkeley, who began
bundling it with their freely distributed version of UNIX, Free BSD. In
1983, DARPA mandated that all new systems connecting to the ARPA network
had to use TCP/IP, thus guaranteeing its long-term success.
To
fully comprehend computer networking using the TCP/IP protocol, it is
necessary to establish the various components of a computer network and
the TCP/IP protocol. Think of a protocol as the language spoken by a
computer. Packets are blocks of information passed between computers
through a median like a telephone wire. Computer networks consists of
hosts and networks. A host is essentially anything on the network that is
capable of receiving and transmitting Internet Protocol (IP) packets on
the network, such as a workstation or a router. These hosts are connected
together by one or more networks. The IP address of any host consists of
its network address plus its own host address on the network. Unlike other
protocols, IP addressing uses one address containing both
network
and host address. The TCP/IP protocol consists of two protocols as the
name suggests. The Transmission Control Protocol (TCP) is the portion of
the protocol that puts together and reads the software packets that are
sent from host-to-host through the network. The IP is the addressing part
of the protocol and is very complex.
Hosts
and networks are considered as nodes. Each node's address is a 32-bit
binary number (see figure 1). For convenience, this is broken into four
8-bit fields separated by a period called an octet. Most modern TCP/IP
products represent these binary octets with their decimal number
equivalents. The maximum decimal value of an eight-bit binary number is
255. The use of decimal numbers instead of binary numbers aids in
readability. Although computers have no trouble dealing with 32-bit binary
strings, humans typically have difficulty reading binary numbers.
Figure 1
8-bit IP Address Decimal Values 192.168.1.20
8-bit IP Address Binary Values 11000000.10101000.00000001.00010100
In contrast to the host-based network architectures of the time, TCP/IP
proved to be useful on a variety of systems without a central controlling
system. With TCP/IP, there is no central authority like IBM SNA networks.
Nodes communicate directly among themselves, and each maintains complete
knowledge about the available network services. If any host fails, none of
the others knows or cares (unless they need data from the down machine, of
course). TCP/IP networks were designed to be robust. In battlefield
conditions, the loss of a node or line is a normal circumstance.
Casualties can be sorted out later, but the network must continue
operating. They automatically reconfigure themselves when something goes
wrong. If there is enough redundancy built into the system, then
communication is maintained. This is very similar to telephone systems
found in most developed countries today.
Routers
perform the task of moving traffic between networks. A node that needs to
send data to another node on another network will send the data to a
router, and the router will then send the data on to the destination node.
If the destination isn't on a directly connected network, the router will
send the data to another router for delivery. The TCP portion of the
protocol was designed to recover from node or line failures where the
network generates routing table changes to all router nodes. Since the
update takes some time, TCP is slow to initiate recovery. The TCP
algorithms are not tuned to optimally handle packet loss due to traffic
congestion. Instead, the traditional Internet response to traffic problems
has been to increase the speed of the lines and equipment in order to stay
ahead of growth and demand.
TCP
treats the data as a stream of bytes. It logically assigns a sequence
number to each byte. The TCP packet has a header that says, in effect,
"This packet starts with byte 379642 and contains 200 bytes of
data." Often packets are sent via different routes and are received
out of sequence. The receiver can detect missing or incorrectly sequenced
packets and requests retransmission. TCP acknowledges data received and
retransmits data that has been lost. The TCP design means that error
recovery is done end-to-end between the two nodes. There is no formal
standard for tracking problems in the middle of the network.
The addressing scheme is broken down into three separate
classes: A, B, and C. Some sites have one very large network with millions
of nodes. They would use the first octet of the address to identify the
network, and the remaining three octets would be used to identify the
individual workstations. This is known as a "Class A" address.
The most common users of "Class A" addresses are network service
providers, who maintain extremely large and flat networks with millions of
nodes. "Class A" addresses are identified by the first bit in
the 32-bit address being set to "0". Since "Class A"
networks only use the first 8 bits for the network number, this leaves
only 7 bits for the network portion of the address. There are only 7
available bits, and only 128 possible networks. Network numbers 000 and
127 are reserved for use, so there are really only 126 possible networks
(001 through 126). However there are 24 bits available for identifying
nodes, for a maximum of 16,777,124 possible hosts for each network.
Another
site may have thousands of nodes, split across many networks. They would
use a "Class B" address. The first two octets are used to
identify the network, and the remaining two octets are used to identify
the individual nodes. Universities and large organizations are the most
common users of "Class B" addresses. "Class B"
addresses are identified by having the first two bits set to
"0". Since they use the first two octets to identify the
network, this leaves 14 bits to identify each network segment. Thus, there
are a possible 16,384 "Class B" addresses, ranging from 128.1 to
191.254 (000 and 255 are reserved).
Finally,
the most common address is the "Class C" address, where the
first three octets are used to identify the segment, and the last octet is
used to identify the workstations. These are good for sites that only have
a few dozen nodes, although they may have many such networks. "Class
C" addresses are identified by having the first three bits in the
first octet set to "0". "Class C" addresses use the
first three octets to identify the network, so there are 21 bits
available. The possible network numbers range from 192.1.1 through
254.254.254, for a grand total of 2,097,152 possible networks. However,
since there is only one octet left to identify the nodes, there can only
be 254 possible devices on each segment (256, minus addresses 000 and
255).
The
advantages of TCP/IP include the following:
Broad
connectivity among all types of computers and servers.
Direct access to the global Internet.
Strong support for routing.
Simple Network Management Protocol support (SNMP).
Support for Dynamic Host Configuration Protocol (DHCP) to dynamically
assign client IP addresses.
Support for the Windows Internet Name Service (WINS) to allow name
browsing among Microsoft clients and servers.
Support for most other Internet protocols, such as Post Office Protocol,
Hypertext Transfer Protocol, and any other protocol acronym ending in P.
Centralized
TCP/IP domain assignment, which allows internetworking between
organizations.
If
you have a network that spans more than one metropolitan area,
you will probably need to use TCP/IP. Think of TCP/IP as the truck of
transport protocols. It's not fast or easy to use, but it is routable over
wide, complex networks and provides more error correction than any other
protocol. TCP/IP is supported on every modern computer and operating
system. Like a truck, TCP/IP has some disadvantages:
TCP/IP
has some disadvantages:
Centralized
TCP/IP domain assignment, which requires registration effort and cost.
Global expansion of the Internet, which has seriously limited availability
of unique domain numbers. A new version of IP will be able to correct this
problem when it is implemented.
Difficulty of setup.
Relatively high overhead to support seamless connectivity and routing.
Slower speed than IPX and Net BEUI.
TCP/IP
is the slowest of all the protocols included with Windows NT.
It is also relatively difficult to administer correctly, although new
tools, such as DHCP, make it a little easier.
To
address the shortage of available IP addresses, IPv6 is being developed.
IPv6 addresses are 128-bit (16 octets) identifiers for interfaces and sets
of interfaces. IPv6 will support four times the number of bits compared to
IPv4 (128 bits versus 32). This corresponds to an address space (296)
times the size of the IPv4 address space. Although this is an extremely
large address space, the assignment and routing of addresses requires the
use of hierarchical schemes that reduce the efficiency of the address
space usage. Nevertheless, it is estimated that, in the worst case,
128-bit IPv6 addresses can accommodate 1018 hosts, which is still
extremely large. Theoretically, this increased address capacity can
accommodate one address for every three square meters of the earth's
surface.
There are three conventions for representing IPv6 addresses as text
strings: the preferred form (full IPv6 address form in hexadecimal
values), the compressed form (with substitution of zero strings), and
mixed form (convenient for mixed environments of IPv4 and IPv6 nodes). An
example of the preferred form is:
FEDC:2A5F:709C:AEBC:97:3154:3D12
An
example of compressed form is where zeroes in address values are omitted,
example:
FF08::209A:61.
This
new naming convention might seem complicated at first because decimal
values are not used. It is still better than reading a string of 16
eight-bit binary numbers. This new naming convention assumes that only
trained technicians will be working with the assignment of IP addresses.
Therefore, readability by the average human is not necessary.
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