EIGRP PACKET TYPES

PACKET TYPE        TYPE OF DELIVERY    MULTICAST/UNICAST    ACK REQ
   
HELLO                     UNRELIABLE                MULTICAST                       NO

UPDATE                   RELIABLE                    MULTICAST                         YES

ACK                         UNRELIABLE                UNICAST                             NO

QUERY                    RELIABLE                   MULTICAST                           YES

REPLY                     RELIABLE                   MULICAST/UNICAST            YES

Types of Communications

1: Broadcast: One to all
eg: AIR: ALL india Radio, Television news etc
eg: I am taking a batch. In batch there are 8 students all understand english.
So when I am speaking in english the message is for every one.
eg: Diwali Season or Christmas : you send a email of Diwali or christmas to every one, to ur parents, brother, sister, girlfriend and friends. a message is for every one.

Hub doesn't understand the ip address, mac address.so he floods the packet to all the interfaces its connected to but it never sends the packet to the same interface from which it was received.

Hub is having one broadcast domain.
Broadcast domain = 1
In hub there is a collision.
Collision Domain = 1

Hub: maximum ports = 24
     minimum ports = 4

What is Hub?

1) Hub is a dump device.
2) Hub is broadcast device.
3) Hub is not as intelligent as Switch
4) Hub is a multipoint repeater.
5) Hub regenrates the signal.
6) Hub works at layer 1.
7) Hub has shared bandwidth every port is of 10mbps.

AND OPERATION IN NETWORK

10101100.00010000.00001010.00001010
11111111.11111111.00000000.00000000.
---------------------------------------
10101100.00010000.00000000.00000000
128+32+8+4
172.16.0.0====Network ID

------------------------------------------------------------------------

00-25-64                           -4f-8e-c9
OUI
Organisation unique Identifier        Vendor assigned


00-25-64-4f-8e-c1
00-25-64-4f-8e-c2
        c3
        c4

CONGESTION RENO

Booting of the router

POST : Power on self test
ROM:
BootStrap: Initializing the router.

Flash

Nvram

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Config register value:

16 bits value

0000    0000    0000    0000

2    1    0    0    -----> Rom monitor mode

2    1    0    1    -----> ROm IOS ( mini-ios)

2    1    0    2    -----> (Default) Normal booting of the router

2    1    4    2    -----> Troubleshooting


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md5 = message digest 5 the encryption mecanism used to encrypt the password