Frame Relay, Asynchronous Transfer Protocol and Metropolitan Ethernet

I have reading a lot of questions regarding Frame relay how it works and how it is related to Asynchronous transfer protocol.
Also many people believe that metropolitan Ethernet is usual Ethernet.


So here I post some information and I hope it clears those confusions.




Frame Relay is a WAN (Wide Area Network) protocol which is cheap and easy to implement,
It is a Packet Switching technology which makes efficient use of the bandwidth that the ISP provides.
It uses LMI (Local Management Interface) which basically means that you need to pay only for the link between you and the ISP rather than the traditional (Circuit switching) where you have to pay for the end to end connection.


Asynchronous Transfer Protocol (AST) it is a time multiplexing mechanism that many of the WAN technologies use, It efficiently uses the bandwidth to transfer any data which is ready to be transmitted.
In Synchronous TP it is basically that every network has a time limit in which it can transmit data, and if at all there is no data that particular segment of data for that network will be transmitted with null data. AST uses the empty spot for any other data that is ready to be transmitted and hence optimizes and enhances network performance.


Metropolitan Ethernet is just an extension of Ethernet as we know, ISP's are now-a-days proposing that the connection between branches of offices, campuses and various other remote sites be connected via Ethernet, but fibre Ethernet known as 1000BaseLx....
This not only will make it faster rate of transmission but also in a way enhance security as the two remote sites will be connected via a Layer 2 protocol rather than upper layer complex protocols.
Also the fact that we all know Ethernet is cheaper than satellite, Wireless, Frame Relay and etc

Some might say in the world of networking any subnetting without VLSM (Variable Length Subnetting Masking) is way too easy, Have a look at this one.....

A Company is given Ip Address 145.72.0.0, they have 30 departments in their company and do not know and also do not want to assume which particular department will need more ip addresses or which department will need less ip addresses, so the clever Network Administrator initiates an idea that he would not use VLSM and devide the addresses in equal parts throughout the departments. How would you subnet it? Explain showing each subnet.

Answer:

Needed 30 EQUAL subnets

So, we need to borrow 5 bits from the host portion of the class B (128.0.0.0 - 192.255.255.255) network

but as we have to borrow 5 bits from network portion we will have two extra subnets.

how?
we borrow 1 bit we get two subnets 0 & 1
borrow 2 bits we get four subnets 00,01,10,11
3 gives 8 subnets 000,001,010,100,011,110,111,101
4 bits gives us 16
and 5 bits gives us 32

now back to our problem.

class B default mask: 255.255.0.0 = 11111111.11111111.00000000.00000000

after borrowing 5 bits from host portion (0 portion)

11111111.11111111.11111~000.00000000 = 255.255.248.0 = /21
* After "~" means start of host portion

starting subnet (0th subnet) = 145.72.0.0 - 145.72.7.255
1st subnet = 145.72.8.0 - 145.72.15.255
2nd subnet = 145.72.16.0 - 145.72.23.255
3rd subnet = 145.72.24.0 - 145.72.31.255
4th subnet = 145.72.32.0 - 145.72.39.255
5th subnet = 145.72.40.0 - 145.72.47.255
6th subnet = 145.72.48.0 - 145.72.55.255
7th subnet = 145.72.56..0 - 145.72.63.255
8th subnet = 145.72.64.0 - 145.72.71.255
9th subnet = 145.72.72.0 - 145.72..79.255
10th subnet = 145.72.80.0 - 145.72.87.255
11th subnet = 145.72.88.0 - 145.72.95.255
12th subnet = 145.72.96.0 - 145.72.103.255
13th subnet = 145.72.104.0 - 145.72.111.255
14th subnet = 145.72.112.0 - 145.72.119.255
15th subnet = 145.72.120.0 - 145.72.127.255
16th subnet = 145.72.128.0 - 145.72.135.255
17th subnet = 145.72.136.0 - 145.72.143.255
18th subnet = 145.72.144.0 - 145.72.151.255
19th subnet = 145.72.152.0 - 145.72.159.255
20th subnet = 145.72.160.0 - 145.72.167.255
21th subnet = 145.72.168.0 - 145.72.175.255
22nd subnet = 145.72.176.0 - 145.72.183.255
23rd subnet = 145.72.184.0 - 145.72.191.255
24th subnet = 145.72.192.0 - 145.72.199.255
25th subnet = 145.72.200.0 - 145.72.207.255
26th subnet = 145.72.208.0 - 145.72.217.255
27th subnet = 145.72.218.0 - 145.72.223.255
28th subnet = 145.72.224.0 - 145.72.231.255
29th subnet = 145.72.232.0 - 145.72.239.255
30th subnet = 145.72.240.0 - 145.72.247.255
31th subnet = 145.72.248.0 - 145.72.255.255

And they say this was easy......

How to determine network address, broadcast address and number of usable host addresses if you are given an ip address.

How to find network address and broadcast address of a given ip address?
also how to find a range of usable host addresses for a given ip address.

In our example we shall use
IP ADDRESS: 192.168.31.5
IP SUBNET MASK: /28 or 255.255.255.240



/28 or 255.255.255.240 = 11111111.11111111.11111111.11110000
192.168.31.5 = 11000000.10101000.00011111.00000101

11111111.11111111.11111111.1111~0000
11000000.10101000.00011111.0000~0101 *"~" means starting of host bits by the mask.

For a network address all the host bits have to be 0
therefore

11111111.11111111.11111111.1111~0000
11000000.10101000.00011111.0000~0000 = 192.168.31.0

For a broadcast address all host bits have to be 1
therefore

11111111.11111111.11111111.1111~0000
11000000.10101000.00011111.0000~1111 = 192.168.31.15

Now, if you want to know how many usable host address we have
remember we cannot use network address and the broadcast address for host addresses, So,
it is always
Square Of (n) - 2
where n is the number of host bits

in our example: n = 4
Square of 4 = 16;
16 - 2 = 14

therefore starting usable host address = 192.168.1.1
ending usable host address = 192.168.1.14

so .1 to .14 are the usable host addresses

For those of you who want to visualize how Java works.....

Hey here is something you would love,
If you are a Programmer in Java, struggling with the flow of Java programs,
Unable to visualize that class is like a collection of attributes
(which is very important for being a good Java programmer).

This is the place you should visit and download the software named as BlueJ.

It works similar to NetBeans and various other IDE for Java....But.........
This one shows UML(Unified Modelling tool)
If you don't know what I mean have a look at this UML Tool in programming link.

It would show you how classes are different, what relation exist in-between them.
I used it and i have been thinking why the hell i did not search for it before.....

The BlueJ website can be found here

click here BlueJ
I play my tribute to Sun Microsystems, La Trobe University,
and special thanks to University of Kent and I thank Damiano Bolla, Michael Cahill, Kasper Fisker, Poul Henriksen, Michael Kölling, Bruce Quig, Davin McCall, Clive Miller, Dave Musicant, Markus Östman, Andrew Patterson, Axel Schmolitzky, Ian Utting, Marion Zalk for giving us such a wonderful tool.