The situation...

“Ravinder, can you check what is wrong with the Internet again,” exclaimed exasperated Manoj Tyagi, Vice President of an investment banking firm in Delhi. “I need to urgently download the presentation that Kartik has sent from Mumbai,” he added.

“I am already printing this 300 page document for the client and need a copy of this presentation to complete it,” he added, raising the alarm bell. The delegate from the UK-based company was expected to reach the office soon.

Ravinder looked at his wrist watch to see the time, and it read 10:30. It had been only an hour into the Monday morning and this was already the fourth call. And all of them were about Internet connectivity.

Unknown to Manoj, Ravinder was already speaking to the service provider on the other line. “Sir, your dedicated 2 Mbps line is working absolutely fine. The problem is at your end. The connectivity is clean and there are no issues,” said the customer care executive. “Please check again, it can’t be,” an irritated Ravinder said.

Ravinder had hit a wall. He was the IT Manager at FreidCorp, an investment banking firm that employed 120 people at the Delhi office. The office was an icon in itself. Designed by a specialist firm from Hong Kong, the office was swank and modern. Everything was wireless, and the equipment had been pre-configured to ensure there were no problems, as some of the senior folks were Mac users.

What really confused and intrigued Ravinder was that everything was working fine. The wireless printing worked well, the backups happened, but the Internet was always a problem. The ISP kept on repeating that there were no issues. But there were issues—all the time.

All Ravinder could think was, “What would Sherlock Holmes do in a situation like this?” Everything, on the face of it, is fine, but something is afoot. Getting to the bottom of mystery was gnawing Ravinder.

The big questions...

• What could be choking the Internet bandwidth at FreidCorp? the dedicated 2 Mbps line seems to be working well at the service provider’s end.
• What should Ravinder do to permanently solve the problem?

Check out the answers...

Build a wired network

By Basant Chaturvedi, Head IT, Perfetti Van Melle India

About me: Consummate tech professional with expertise on SAP platform. In the past have been associated with Basell India and Seagram India

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What could be choking the Internet bandwidth at FreidCorp? the dedicated 2 Mbps line seems to be working well at the service provider’s end.
The closest analogy to this problem is that your car hit a bottleneck. That’s because the eight-lane freeway you are driving on has terminated into a two-lane road. The reasons could be many.

Printing a 300-page document over the Internet could be resulting in massive data flow from the end-user machine to the print spooler, which can cause the pipe to choke. Since the same content goes to copying and printing, the server will need time to respond, and it could be causing the delay.

Besides, copying a 300-page document can also lead to  a surge in Common Internet File System (CIFS) traffic, with huge TCP acknowledgement flowing through the same line.

The other notable point is that all 120 users at FreidCorp and the entire IT resource are on wireless, which is limited to 54 Mbps. Ravinder’s problem could be getting compounded by the fact that a lot of data—file transfers, data backups and printouts—is also flowing through the same network. Since all the devices in the office are wireless, such data flows can clog the network.

There could be other possible reasons. Since its the beginning of the business hour, and a Monday, there is a possibility that the security templates are getting applied on user machines.

Also, antivirus and software definition updates could be running when users log-in to the business network. Though the line connectivity is reported to be normal, a  high latency rate could be causing the delay, and thereby choking the pipe.

What should Ravinder do to permanently solve the problem?
Ravinder needs to build a wired network for backup, printing and FTP services. The wires in the FreidCorp office will free the wireless network from a lot of data packets. The WiFi network can then complement and augment the wired network, instead of substituting it. He can also prioritise a key user group on wireless rather than putting everybody on it.

Besides, there is a need to sensitise users that large documents should be downloaded from remote servers to the local desktops before printing. This will make the printing traffic local, and save a large amount of Internet bandwidth. Copying of large files is classified under CIFs traffic, and other methods like portals, FTP, and managed downloads can be considered to improve speed.

He could also explore the option of payload compression hardware and software that can help reduce the line utilisation while copying large documents.

In case it is not already done, he should look at securing the wireless network first and hide the SSID broadcast, so that only legitimate users are able to connect to the wireless network. Also, the back-up window can be planned in a way that it doesn’t clash with the peak business hours.

Check connectivity strings

By Falgun Shukla, Sr General Manager (IT), Hikal Ltd

About me: An advance accountancy graduate who ventured into the field of IT and technology and stayed put. Has been in the industry for over two decades, of which the past eight have been with Hikal

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What could be choking the Internet bandwidth at FreidCorp? the dedicated 2 Mbps line seems to be working well at the service provider’s end.
At times, it is hard to pinpoint the problem till all the issues have been studied in depth. There could be several factors responsible for choking the Internet bandwidth at FreidCorp.

In many enterprises like this, the network uses multiple wireless routers and switches to create a local wireless mesh network, which is uplinked to the gateway router. This connectivity between internal and external network needs to be checked.

In such cases, local processes like printing and file sharing will work because there is no local connectivity problem. Also, connectivity between ISP and the gateway router will work perfectly, and that is the reason the ISP did not find any problem in the connectivity. There is a possibility that the local network is not properly connected to gateway router.

FreidCorp’s network might also be suffering from Denial of Services (DoS), Trojan or worm attacks. In such cases, while the connectivity to ISP may work fine, the network under hacker attack or because of internal malicious attacks could experience slow Internet connectivity.

Also, it could be a proxy issue—if Ravinder has a proxy or firewall set up then he should check whether the users are permitted to use it. There could be a possibility of caching overflow or blocking, so he should initialise the cache and restart the network.

What should Ravinder do to permanently solve the problem?
To resolve the issue, Ravinder should ensure that the local network is properly connected to gateway router, and conduct regular check for proper connectivity strings. He should also ping the gateway router and ISP router to verify connectivity, and both the networks.

If it is the security issue that is creating the problem, Ravinder should isolate the problem and clean the network. The communication should be renewed only after putting in place a mechanism to properly monitor the routing packets.

He should also review the firewall settings and other security rules to avoid such incidents. Ravinder should also check the DNS resolution on the user’s work station by using NSlookup to ensure that DNS resolution is happening properly.

Control unofficial bandwidth

By Suresh A Shanmugam, Head-Business IT Solutions, Mahindra & Mahindra Financial Services (M&MFS)

About me: Member of the Shadow Board  on IT  in M&MFS. Was associate with Appsoft in the past

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What could be choking the Internet bandwidth at FreidCorp? the dedicated 2 Mbps line seems to be working well at the service provider’s end.
Choking of bandwidth is an issue that many enterprises grapple with, and the cause could be either the internal network or at the ISP end.

At the user-end, high volume of discreet content uploads or downloads can choke the pipe. Similarly, online games, streaming media applications, peer-to-peer file sharing and such application all consume high bandwidth.

If all these factors are not the cause, then it could be the issue of physical connectivity and hardware. Improper firewall configuration could also be the culprit. Finally, it could also be virus, worms, spyware or Trojans that are causing the bandwidth to choke.

What should Ravinder do to permanently solve the problem?
Ravinder needs to take some basic steps to resolve the problem. First, he should check if there are any connectivity and bandwidth issues from the service provider’s end, and whether the ISP is indeed providing 2 Mbps connectivity.

While he needs to check the firewall configuration for proper access control, it is also important to control Internet usage through proper policy implementation, and ensure that adequate security measures are in place at the user end.

It is also quite possible that FreidCorp has peaked ‘official’ bandwidth usage. In this case the only way is to upgrade bandwidth and go for a backup link from a different vendor. However, Ravinder should certainly map the company’s existing and ‘near future‘ requirements before deciding to get a backup link.