TCP / IP

It is a open standard protocol which is supported in all networks

THERE ARE FIVE COMPONENTS :

MESSAGE

SENDER

RECEIVER

MEDIUM

DEFINITION :

• it is a protocol used for communication between two host otherwise the protocol used for connectiong hosts on the internet

consider there are two systems named system A and system B.if both the system wants to communicate with each other, there is a physical path for them to communicate.here, NETWORK acts as the transporting medium between these two system for communicating.

NETWORKS:

network is broadly classified as two types.

1.point to point network

2.multi access network

multi access network is classified as

(i)broadcast multi access network

(II)non-broadcast multi access network

consider, if one system wants to share its data with the another system and the file (data) which is getting transferred is a larger file, then there will be problem in sending.

inorder to debug it, the source system breaks the file into some segments and then sends it to the destination system.after receiving those data, the destination system re-configure it to get the whole file.this process is called as segmentation and re-assembling.the small segments are identified by sequence number

IP ADDRESSING:

there are two types:

(i)IPV4

(II)IPV6

since we use IPV4 currently, we shall discuss about it now..

range of IPV4 is from 0 . 0 . 0 . 0 to 255 . 255 . 255 . 255.

these are called as dotted decimal format.

IP address is widely classified as 5 types:

class A

class B

class C

class D

class E

where class A,B,C are used for LAN & WAN purpose, class D are reserved for multicasting and class E are reserved for research and development (R & D).

ADDRESS TYPES:

1.UNICAST ( one to one )

2.MULTICAST ( one to group )

3.BROADCAST ( one to many or all )

_{RANGE OF CLASSES:}

_{class A ( 0 - 127 ) --> ( 1-126 )}

_{class B ( 128 - 191 )}

_{class C ( 192 - 223 )}

_{class D ( 224  - 239 )}

_{class E ( 240 - 255 )}

* in class A, 0 and 127 are reserved for some other functions.that is why it is denoted with the arrow as final ( 1 - 126 )

IP ADDRESS:

* it is a combination of NETWORK part and HOST part.

* each IP address consist of 4 octets.

CLASS A :

in class A, 1st octet is consider as NETWORK part and the rest 3 octet are reserved as HOST part.

here, no of network bits:                8

        no of host bits:                    24

        total no of networks:           126

        total no of hosts             16777216    

CLASS B:

in class B, 1st and 2nd octet are consider as NETWORK part whwreas 3rd and 4th octet are reserved for HOST part.

here, no of network bits:                16

        no of host bits:                     16

        total no of networks:           16384

        total no of hosts                 65534

CLASS C:

in class C, 1st, 2nd and 3rd octet are consider as NETWORK part and 4th octet alone is HOST part.

here, no of network bits:                24

        no of host bits:                      8

        total no of networks:         1048576 

        total no of bits                     254

to find

(I) NETWORK ID, put zero in all the host part.

(II) FHID ( FIRST HOST ID ) , put zero in all except the last bit put one.

(III) LHID ( LAST HOST ID ) , put one in all except last bit, put zero.

(IV) BIP ( BROADCAST IP ) , put one in all bits.

_{SUBNET MASK:}

* differentiates network portion and host portion

* consider

   network part -> 1

   host part      -> 0