INET

In the past few articles I have been writing about how to communicate using modems. While a lot of ground has been covered there, we have been assuming that you are calling from one place to another via a direct telephone call.

This is OK if you are talking about calling within the same city, since it is just a local call. Once you start communicating with computers that are in another city, a new (and nasty) factor shows up - long distance phone charges.

"Aaaaarrrrrrggghhhhhh!!!!!!"

The above expletive is heard in most offices at least once every two months - the time when the phone bill arrives.

Phone bills are so high due to two factors - the totally unreasonable tariff that our phone company places on us, and our own incredible desire to talk/communicate for as long as possible once we make a connection.

The first factor is something we can do very little about (apart from praying daily for privatisation in the telecom business). Unless all of us decide to shift office hours to after 10pm at night (when phone rates are at their lowest), it is unlikely that we are going to see any lowering of the phone tariff.

The second factor is human nature, and I am no judge of mankind, so I won't try and discuss that here.

Instead, I'll introduce you to another way of extending your reach that doesn't cost as much as a STD/ISD call.

The Big Controversy

No aspect of Indian Telecommunication has created so much controversy and misunderstanding as the facility introduced by the D.O.T in 1992 - INET.

The controversy arose from the fact that no one, including the D.O.T. people themselves, could clearly say what INET was all about - was it a service, was it a facilty, what could one do with it, was it cheaper than STD, etc.

The misunderstandings arose when the above questions were not clearly answered.

I am not the D.O.T., but I hope that by the time you finish reading this article, you'll understand and appreciate INET much more.

Understanding INET

To make things very simple to understand, let's look back at how a modem works - it converts a computer's digital signals to audio tones so that it can send them over the phone line, and at the far end another modem turns these audio tones back to digital signals.

This convoluted process is necessary because the telephone lines were not meant to carry electrical (digital) signals.

But imagine that someone rigs up a bunch of phone lines across the country that can transfer digital signals (data) instead of voice. And, because this data was controlled by computers, it could maintain many connections over a single line. And, because of this "multiplexing", the rates were MUCH lower than a STD call.

Seems like a dream ? But it isn't ! What I have just described is an X.25 carrier network. (As usual, X.25 is YET another CCITT label for some standard or the other, and in itself tells you nothing except that it is official.)

INET is such an X.25 network.

X.25 - looking under the hood

How does an X.25 network perform this miracle ?

Actually, it is quite simple. What happens is that the network uses an X.25 Packet Assembler-Disassembler (PAD) to break the data it receives into little packets, each one carrying "address" information that can be used to guide it to its final destination.

Then the network throws these little packets into a big stream of data that flows throughout the country. The stream consists of thousands of data packets. As the stream of data flows through each city, the local PAD examines each packet's address information. If it is meant for that city, then it diverts this packet to it's final destination within the city, and lets the other packets continue on their journey.

This sounds complex and slow, but in reality it is fast - VERY fast - because the PAD-to-PAD links are pure digital lines that let the PADs talk to each other at upto 64000 bits per second, or almost 30 times the speed of your ordinary 2400 bps modem ! This is in theory - in India, INET PADs are linked by 9600 bps lines as I am writing this, which is late March - but at a recent INET meet, we were promised 64Kbps links between PADs sometime in June/July. Pity they didn't specify which year.

Anyway, this speed is divided over the users connected to the network, so that the net throughput is not much less than a direct modem connection. And, because the X.25 network is servicing many people at the same time, the line costs per user are much lower, since physically only one line is in use !

Sounds great ! So lets throw away our modems and use INET instead !

Er...nice try, but no cigar.

Connecting to INET

To connect to INET, you still need a modem. INET PADs are spread across the country, in all the metros (Bombay, Delhi, Madras and Calcutta) plus a few non-metros (Pune, Hyderabad, Ahmedabad). Yep, there is one even in Bangalore (hurray!) which is STILL classified as a non-metro (booooo!).

So to get connected to your nearest INET PAD, you have to fire up your modem and call to a local INET number. That's not too bad, because it is a local call.

OK, so once you are connected to INET, what do you do ? Can you directly log into my BBS in Bangalore from Delhi ?

Unfortunately - no. At least not yet.

INET Connections

There are three kinds of INET connections -

- X.28 Dialup lines - X.28 Leased lines - X.25 leased lines

INET X.28 dialups allow you to ORIGINATE calls, but not receive any.

X.28 leased lines DO allow you to receive calls, but the provided X.28 leased lines are so terrible, under-featured and useless that they can actually be only used for calling out, by people who don't like making phone calls with their modems. If you have an X.28 leased line, you'll know what I am talking about. If you don't have one, count your blessings. X.28 leased lines are SO useless that I will not sully my column any further with any reference to them.

You have to have an X.25 leased line to be able to RECEIVE calls via INET. X.25 leased lines are phenomenally expensive, and getting worse. I took a nap the other day, and when I woke up, INET had raised its tariff for X.25 leased lines. To top that, you need to buy expensive X.25 equipment. The whole exercise can cost you as much as 1.5 to 2 lakhs, not counting line rentals.

So what CAN you call using INET ?

Well, to start with, you can connect to many international services such as Compuserve, MCI Mail, Bix and Dialog. Many of these require you to have a means of paying by a credit card valid outside India (which at this time is not possible unless you have benefactors abroad). The tariff for international calls via INET is Rs.200 per 64 KB of data plus Rs.4 per minute. The same 64 KB would cost you about Rs.350 if you were to call ISD.

Also, many companies in India now are setting up X.25 hosts accessible via INET. All but a few of them are completely private, meant for intra-company communications only. But some have recently thrown open their services to the public. At least three software companies I know of are planning to make their support BBS available on INET.

And finally, there is something new brewing.

INET "DialOut"

INET recently announced that they would allow "dial-out" from INET connections to non-INET subscribers. This would be something like dialling from Delhi to Bangalore on STD, but at the lower rates that are typical of INET. For example, a call from Delhi to Bangalore would cost you Rs.50 per 64 K of data. During daytime, such an exercise would cost you about Rs.160 on STD, so the savings are obvious.

Now THAT will really add a new twist. You would be able to connect to any communication host in the country at a tariff much lower than STD, even if the host itself is not running on INET.

How will this work ? Simple, actually. You connect to INET in your city, provide the phone number in the remote city along with a special code, and the call is routed to the INET PAD nearest to the called number. From there, the PAD will use a modem to dial out to the requested number, and that's it.

At the time of writing, this facility is not yet available, but is under test in select locations in India, and is expected to be available to the rest of the country sometime this year. (To quote the king of computer journalists, Jerry Pournelle - "Real Soon Now").

Where do you go from here ?

Well, to begin with, I'd suggest that you get yourself an INET X.28 dial-up account in your city. This will cost you about Rs.2000 initially, and will take you between 2-3 months, though INET is known to spring surprises - a friend of mine recently applied and got his account in a month's time !

If you plan to set up a host yourself, you got the choice of blowing 2 lakhs on an X.25 connection, which will take you about a year to get.

Or you could wait for the INET DialOut facility, which we hope to see this year.

There are about 150 companies at this time who have X.25 leased line connections in India, and about 1000 X.28 dialup subscribers. The latter is likely to increase by a factor of 5 over the next year, making it more and more difficult to get such connections, so better get cracking right away.

If you are in charge of the communications department of a largish corporation, earn brownie points by investigating the use of X.25 lines. You will need one X.25 leased line to your head office (or wherever you plan to install the host), and X.28 dialup accounts in the various cities where you have your offices. The total cost of setting up the host should be between 2-3 lakhs, plus about Rs.2000 per for each outstation office X.28 dialup account.

One bonus for corporations is that if you have an X.25 host running, you can accept "Reverse Charge" calls. This means that you remote office places the call and connects to your host, but the INET charges are debited to you central account ! It is almost as if the central host has originated the call, so effective INET charges at the remote office end will be almost nil (apart from minimum charges).

INET Issues

There are some issues that you should be aware of when dealing with INET. INET is a "new kid on the block" and, though already active and useful, will show up with a few problems every now and then.

The biggest one you'll run into is network congestion, caused by the "slow" inter-PAD connections of INET. This should be resolved soon.

The second one concerns file transfers. INET X.25 operations are not as transperant as one would wish them to be, so you may have trouble while transferring files using XMODEM or YMODEM. ZMODEM and KERMIT are fine, but still require some special setup. Work is afoot to resolve this, and I'll keep you informed through this column on its progress.

The third problem is that of confusion. The INET staff at times cannot help you because they themselves do not have sufficient information at hand. This problem, too, should be history once INET settles in properly.

Winding up

Yikes, page three already ?

OK, time to wind up. Next month, I take a break from "monologing" and will provide answers to a whole bunch of questions that I have been receiving via my BBS, post and phone calls. After all, if PCQUEST and myself don't answer your questions, who will ?

Beep, beep !