Example 1e: 255.255.128 [/25]Solution: Using class C network address Since 128 is 10000000 in binary, here = 1bit for subnet and y = 7 bits for hosts.
192.1688.10.0 = Network address = Subnet mask.

  1. How many subnets?
    Since 128 is 1 bit on [10000000], the answer would be 2 = 2.
  2. How many valid hosts per subnet? [Numbers of 2 bit]7 host bits off [10000000], 2 – 2 = 126 hosts.
  3. What are the block sizes? 256 – 128 = 128
  4. Write out the subnet address for each subnet.
    The number right before the value of the
    NO. 3 ANSWERS.
    = 128
    NO. 4 ANSWERS.
    Subnet 0.0 128.0
    First host 0.1 128.1
  5. Broadcast Address for each subnet?
    Last host 127.254 255.254
    Broadcast 127.255 255.255
    i.) How many subnets can be produced from each mask?

Mask A =
128 = 10000000. So therefore, 128 has one bit on it 2^1 = 2 subnets.
Mask B =
192 has 2 bit on it 11000000
2^2 = 4 subnets
ii.) How many valid hosts per subnets are available?
For A = 2^7 – 2; = 128 – 2; = 126 valid host
B = 2^6 – 2; = 64 – 2; = 62 valid host
A = 7 bits off
B = 6 bits off
iii.) What is the block size of each mask?
For A = 256 – 128 = 128
B = 256 – 192 = 64
Increment for A is from 0, 128 but real subnetting values are 0.0, 128.0
Increment for B is from 0, 64, and 128
iv.) What are the valid hosts in each subnet?
For A = 2^7 – 2 = 128 – 2 = 126
B = 2^6 – 2 = 64 – 2 = 62
v.) What is the broadcast address of each subnet?
Broadcast address is always the number at the carrier after the subnet address
Subnet address: 126,252
What is digital transmission?
It is the physical transfer of data [a digital bit stream] over a point-to-point or point-to-multiple communication channel. Examples of such channels are copper wires, optical fibers, wireless, and communication channel and storage media. The data are represented as an electromagnetic signal, such as electrical voltage, radio wave, microwave, or infrared signal. It is the transfer of discrete messages. The messages are either represented by a sequence of fuist by means of line code.
3a.) Complete a table by listing every available subnet mask and its equivalent class inter domain routing [CIDR] slash notation starting from slash 8 [/8] to slash 30 [/30] [6 marks]SOLUTION.
What is subnet mask?
It is a 32 bit value that allows the recipient of JP packets of distinguishing the network ID portion of the IP address from the host ID portion of the IP address.
What is CIDR [Classic Inter-domain Routine]?
This can be define as the method or ways in which ISP [Internet Service Provider] allocate or distribute a number of address to house, office etc.

This can be defined as a standard program develop to enhance method of transmitting and processing of various kinds of information from one device to another either by wired or wireless.

(1) TCP/IP
Transmission Control Protocol: this involves way of creating a packet and putting them in direct order and checking that no packet got loss at the transmission.
(2) IP: it is a means to channel information to the proper address.
(I) VDP: It is use with the IP when small amount of information involved.
(ii) ICMP: It is use for diagnosis and management purpose for small messages.
(4) Interactive Mail Access Protocol [IMAP]: It allows reading of individual mail box at a single account and commonly business environments.
(5)HTTP [Hyper Text Transfer Protocol]


Oluwamuyide Peter

On the 4th of November I officially became a member of the exclusive 1st student with distinction after five years of no such record, in the history of The Polytechnic Ibadan, Faculty of Engineering to graduate with distinction as a DPP students since its establishment in 2011. My unrelenting power to solve problems, have made me to create a platform where student can get valid information anywhere, anyplace at anytime Evolving education world wide 🌎

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