Why Caching Alone Will Not Solve Your Congestion Issue


Editors Note:
The intent of this article to is to help set appropriate expectations of using a caching server on an uncontrolled Internet link. There are some great speed gains to be had with a caching server; however, caching alone will not remedy a heavily congested Internet connection.

Are you going down the path of using a caching server (such as Squid) to decrease peak usage load on a congested Internet link? 

You might be surprised to learn that Internet link congestion cannot be mitigated with a caching server alone. Contention can only be eliminated by:

1) Increasing bandwidth

2) Some form of bandwidth control

3) Or a combination of 1) and 2)

A common assumption about caching is that somehow you will be able to cache a large portion of common web content – such that a significant amount of your user traffic will not traverse your backbone to your provider. Unfortunately, caching a large portion of web content to attain a significant hit ratio is not practical, and here is why:

Lets say your Internet trunk delivers 100 megabits and is heavily saturated prior to implementing caching or a bandwidth control solution. What happens when you add a caching server to the mix?

From our experience, a good hit rate to cache will likely not exceed 10 percent. Yes, we have heard claims of 50 percent, but have not seen this in practice. We assume this is an urban myth or just a special case.

Why is the hit rate at best only 10 percent?

Because the Internet is huge relative to a cache, and you can only cache a tiny fraction of total Internet content. Even Google, with billions invested in data storage, does not come close. You can attempt to keep trending popular content in the cache, but the majority of access requests to the Internet will tend to be somewhat random and impossible to anticipate. Yes, a good number of hits might hit the Yahoo home page and read the popular articles, but many users more are going to do unique things. For example, common hits like email and Facebook are all very different for each user, and cannot be maintained in the cache. User hobbies are also all different, and thus they traverse different web pages and watch different videos. The point is you can’t anticipate this data and keep it in a local cache any more reliably than guessing the weather long term. You can get a small statistical advantage, and that accounts for the 10 percent that you get right.

Note: Without a statistical advantage your hit rate would be effectively be 0.

Even with caching at a 10 percent hit rate, your link traffic will not decline.

With caching in place, any gain in efficiency will be countered by a corresponding increase in total usage. Why is this?

If you assume a 10 percent hit rate to cache, you will end up getting a 10 percent increase in Internet usage and thus, if your pipe to the Internet was near congestion when you put the caching solution in, it will still be congested. Yes, the hits to cache will be fast and amazing, but the 90 percent of the hits that do not come from the cache will equal 100 percent of your Internet link. The resulting effect will be that 90 percent of your Internet accesses will be sluggish due to the congested link.

Another way to understand is by practical example.

Let’s start with a very congested 100 megabit Internet link. Web hits are slow, YouTube takes forever, email responses are slow, and Skype calls break up. To solve these issues, you put in a caching server.

Now 10 percent of your hits come from cache, but since you did nothing to mitigate overall bandwidth usage, your users will simply eat up the extra 10 percent from cache and then some. It is like giving a drug addict a free hit of their preferred drug. If you serve up a fast YouTube, it will just encourage more YouTube usage.

Even with a good caching solution in place, if somebody tries to access Grandma’s Facebook page, it will have to come over the congested link, and it may time out and not load right away. Or, if somebody makes a Skype call it will still be slow. In other words, the 90 percent of the hits not in cache are still slow even though some video and some pages play fast, so the question is:

If 10 percent of your traffic is really fast, and 90 percent is doggedly slow, did your caching solution help?

The answer is yes, of course it helped, 10 percent of users are getting nice, uninterrupted YouTube. It just may not seem that way when the complaints keep rolling in. :)

YouTube Dominates Video Viewership in U.S.


Editor’s Note: Updated July 27th, 2011 with material from www.pewinternet.org:

YouTube studies are continuing to confirm what I’m sure we all are seeing – that Americans are creating, sharing and viewing video online more than ever, this according to a Pew Research Center Internet & American Life Project study released Tuesday.

According to Pew, fully 71% of online Americans use video-sharing sites such as YouTube and Vimeo, up from 66% a year earlier. The use of video-sharing sites on any given day also jumped five percentage points, from 23% of online Americans in May 2010 to 28% in May 2011.  This figure (28%) is slightly lower than the 33% Video Metrix reported in June, but is still significant.

To download or read the fully study, click on this link:  http://pewinternet.org/Reports/2011/Video-sharing-sites/Report.aspx

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YouTube viewership in May 2011 was approximately 33 percent of video viewed on the Internet in the U.S., according to data from the comScore Video Metrix released on June 17, 2011.

Google sites, driven primarily by video viewing at YouTube.com, ranked as the top online video content property in May with 147.2 million unique viewers, which was 83 percent of the total unique viewers tracked.  Google Sites had the highest number of viewing sessions with more than 2.1 billion, and highest time spent per viewer at 311 minutes, crossing the five-hour mark for the first time.

To read more on the data released by comScore, click here.  comScore, Inc. (NASDAQ: SCOR) is a global leader in measuring the digital world and preferred source of digital business analytics. For more information, please visit www.comscore.com/companyinfo.

This trend further confirms why our NetEqualizer Caching Option (NCO) is geared to caching YouTube videos. While NCO will cache any file sized from 2MB-40MB traversing port 80, the main target content is YouTube.  To read more about the NetEqualizer Caching Option to see if it’s a fit for your organization, read our YouTube Caching FAQ or contact Sales at sales@apconnections.net.

Nine Tips and Technologies for Network WAN Optimization


By Art Reisman

Art Reisman CTO www.netequalizer.com

Editor’s note: Art Reisman is the CTO of APconnections. APconnections designs and manufactures the popular NetEqualizer bandwidth shaper.

Although there is no way to actually make your true WAN speed faster, here are some tips for  corporate IT professionals that can make better use of the bandwidth you already have, thus providing the illusion of a faster pipe.

1) Caching — How  does it work and is it a good idea?

Caching servers have built-in intelligence to store the most recently and most frequently requested information, thus preventing future requests from traversing a WAN/Internet link unnecessarily.

Caching servers keep a time stamp of their last update to data. If the page time stamp has not changed since the last time a user has accessed the page, the caching server will present a local stored copy of the Web page, saving the time it would take to load the page from across the Internet.

Caching on your WAN link in some instances can reduce traffic by 50 percent or more. For example, if your employees are making a run on the latest PDF explaining their benefits, without caching each access would traverse the WAN link to a central server duplicating the data across the link many times over. With caching, they will receive a local copy from the caching server.

What is the downside of caching?

There are two main issues that can arise with caching:

a) Keeping the cache current –If you access a cache page that is not current you are at risk of getting old and incorrect information. Some things you may never want to be cached. For example, the results of a transactional database query. It’s not that these problems are insurmountable, but there is always the risk the data in cache will not be synchronized with changes. I personally have been misled by old data from my cache on several occasions.

b) Volume – There are some 300 million websites on the Internet. Each site contains upwards of several megabytes of public information. The amount of data is staggering and even the smartest caching scheme cannot account for the variation in usage patterns among users and the likelihood they will hit an uncached page.

We recommend Squid as a proxy solution.

2) Protocol Spoofing

Historically, there have been client server applications developed for an internal LAN. Many of these applications are considered chatty. For example, to complete a transaction between a client and server, tens of messages may be transmitted when perhaps one or two would suffice. Everything was fine until companies, for logistical and other reasons, extended their LANs across the globe using WAN links to tie different locations together.

To get a better visual on what goes on in a chatty application perhaps an analogy will help. It’s like  sending family members your summer vacation pictures, and, for some insane reason, putting each picture in a separate envelope and mailing them individually on the same mail run. Obviously, this would be extremely inefficient, just as chatty applications can be.

What protocol spoofing accomplishes is to “fake out” the client or server side of the transaction and then send a more compact version of the transaction over the Internet (i.e., put all the pictures in one envelope and send it on your behalf, thus saving you postage).

For more information, visit the Protocol Spoofing page at WANOptimization.org.

3) Compression

At first glance, the term compression seems intuitively obvious. Most people have at one time or another extracted a compressed Windows ZIP file. If you examine the file sizes pre- and post-extraction, it reveals there is more data on the hard drive after the extraction. Well, WAN compression products use some of the same principles, only they compress the data on the WAN link and decompress it automatically once delivered, thus saving space on the link, making the network more efficient. Even though you likely understand compression on a Windows file conceptually, it would be wise to understand what is really going on under the hood during compression before making an investment to reduce network costs. Here are two questions to consider.

a) How Does it Work? — A good and easy way to visualize data compression is comparing it to the use of short hand when taking dictation. By using a single symbol for common words a scribe can take written dictation much faster than if he were to spell out each word. The basic principle behind compression techniques is to use shortcuts to represent common data.

Commercial compression algorithms, although similar in principle, can vary widely in practice. Each company offering a solution typically has its own trade secrets that they closely guard for a competitive advantage. However, there are a few general rules common to all strategies. One technique is to encode a repeated character within a data file. For a simple example, let’s suppose we were compressing this very document and as a format separator we had a row with a solid dash.

The data for this solid dash line is comprised of approximately 160 times the ASCII character “-�. When transporting the document across a WAN link without compression, this line of document would require 80 bytes of data, but with clever compression, we can encode this using a special notation “-� X 160.

The compression device at the front end would read the 160 character line and realize,”Duh, this is stupid. Why send the same character 160 times in a row?” So, it would incorporate a special code to depict the data more efficiently.

Perhaps that was obvious, but it is important know a little bit about compression techniques to understand the limits of their effectiveness. There are many types of data that cannot be efficiently compressed.

For example, many image and voice recordings are already optimized and there is very little improvement in data size that can be accomplished with compression techniques. The companies that sell compression based solutions should be able to provide you with profiles on what to expect based on the type of data sent on your WAN link.

b) What are the downsides? — Compression always requires equipment at both ends of the link and results can be sporadic depending on the traffic type.

If you’re looking for compression vendors, we recommend FatPipe, Juniper Networks

4) Requesting Text Only from Browsers on Remote Links

Editors note: Although this may seem a bit archaic and backwoods, it can be effective in a pinch to keep a remote office up and running.

If you are stuck with a dial-up or slower WAN connection, have your users set their browsers to text-only mode. However, while this will speed up general browsing and e-mail, it will do nothing to speed up more bandwidth intensive activities like video conferencing. The reason why text only can be effective is that  most Web pages are loaded with graphics which take up the bulk of the load time. If you’re desperate, switching to text-only will eliminate the graphics and save you quite a bit of time.

5) Application Shaping on Your WAN Link

Editor’s Note: Application shaping is appropriate for corporate IT administrators and is generally not a practical solution for a home user. Makers of application shapers include Packeteer and Allot and are typically out of the price range for many smaller networks and home users.

One of the most popular and intuitive forms of optimizing bandwidth is a method called “application shaping,” with aliases of “traffic shaping,” “bandwidth control,” and perhaps a few others thrown in for good measure. For the IT manager that is held accountable for everything that can and will go wrong on a network, or the CIO that needs to manage network usage policies, this is a dream come true. If you can divvy up portions of your WAN/Internet link to various applications, then you can take control of your network and ensure that important traffic has sufficient bandwidth.

At the center of application shaping is the ability to identify traffic by type.  For example, identifying between Citrix traffic, streaming audio, Kazaa peer-to-peer, or something else. However, this approach is not without its drawbacks.

Here are a few common questions potential users of application shaping generally ask.

a) Can you control applications with just a firewall or do you need a special product? — Many applications are expected to use Internet ports when communicating across the Web. An Internet port is part of an Internet address, and many firewall products can easily identify ports and block or limit them. For example, the “FTP” application commonly used for downloading files uses the well known “port 21.”

The fallacy with this scheme, as many operators soon find out, is that there are many applications that do not consistently use a fixed port for communication. Many application writers have no desire to be easily classified. In fact, they don’t want IT personnel to block them at all, so they deliberately design applications to not conform to any formal port assignment scheme. For this reason, any product that aims to block or alter application flows by port should be avoided if your primary mission is to control applications by type.

b) So, if standard firewalls are inadequate at blocking applications by port, what can help?

As you are likely aware, all traffic on the Internet travels around in what is called an IP packet. An IP packet can very simply be thought of as a string of characters moving from Computer A to Computer B. The string of characters is called the “payload,” much like the freight inside a railroad car. On the outside of this payload, or data, is the address where it is being sent. These two elements, the address and the payload, comprise the complete IP packet.

In the case of different applications on the Internet, we would expect to see different kinds of payloads. For example, let’s take the example of a skyscraper being transported from New York to Los Angeles. How could this be done using a freight train? Common sense suggests that one would disassemble the office tower, stuff it into as many freight cars as it takes to transport it, and then when the train arrived in Los Angeles hopefully the workers on the other end would have the instructions on how to reassemble the tower.

Well, this analogy works with almost anything that is sent across the Internet, only the payload is some form of data, not a physical hunk of bricks, metal and wires. If we were sending a Word document as an e-mail attachment, guess what, the contents of the document would be disassembled into a bunch of IP packets and sent to the receiving e-mail client where it would be re-assembled. If I looked at the payload of each Internet packet in transit, I could actually see snippets of the document in each packet and could quite easily read the words as they went by.

At the heart of all current application shaping products is special software that examines the content of Internet packets, and through various pattern matching techniques, determines what type of application a particular flow is. Once a flow is determined, then the application shaping tool can enforce the operators policies on that flow. Some examples of policy are:

  • Limit Citrix traffic to 100kbs
  • Reserve 500kbs for Shoretel voice traffic

The list of rules you can apply to traffic types and flow is unlimited. However, there is a  downside to application shaping of which you should be aware. Here are a few:

  • The number of applications on the Internet is a moving target. The best application shaping tools do a very good job of identifying several thousand of them, and yet there will always be some traffic that is unknown (estimated at 10 percent by experts from the leading manufacturers). The unknown traffic is lumped into the unknown classification and an operator must make a blanket decision on how to shape this class. Is it important? Is it not? Suppose the important traffic was streaming audio for a Web cast and is not classified. Well, you get the picture. Although theory behind application shaping by type is a noble one, the cost for a company to stay up to date is large and there are cracks.
  • Even if the application spectrum could be completely classified, the spectrum of applications constantly changes. You must keep licenses current to ensure you have the latest in detection capabilities. And even then it can be quite a task to constantly analyze and change the mix of policies on your network. As bandwidth costs lessen, how much human time should be spent divvying up and creating ever more complex policies to optimize your WAN traffic?

6) Test Your WAN-Link Speed

A common issues with slow WAN link service is that your provider is not giving you what they have advertised.

For more information, see The Real Meaning of Comcast Generosity.

7) Make Sure There Is No Interference on Your Wireless Point-to-Point WAN Link

If the signal between locations served by a point to point link are weak, the wireless equipment will automatically downgrade its service to a slower speed. We have seen this many times where a customer believes they have perhaps a 40-megabit backhaul link and perhaps are only realizing five megabits.

8) Deploy a Fairness Device to Smooth Out Those Rough Patches During Contentious Busy Hours

Yes, this is the NetEqualizer News Blog, but with all bias aside, these things work great. If you are in an office sharing an Internet feed with various users, the NetEqualizer will keep aggressive bandwidth users from crowding others out. No, it cannot create additional bandwidth on your pipe, but it will eliminate the gridlock caused  by your colleague  in the next cubicle  downloading a Microsoft service pack.

Yes, there are other devices on the market (like your fancy router), but the NetEqualizer was specifically designed for that mission.

9) Bonus Tip: Kill All of Those Security Devices and See What Happens

With recent out break of the H1N1 virus, it reminded me of  how sometimes the symptoms and carnage from a vaccine are worse than the disease it claims to cure. Well, the same holds true for your security protection hardware on your network. From proxies to firewalls, underpowered equipment can be the biggest choke point on your network.

Created by APconnections, the NetEqualizer is a plug-and-play bandwidth control and WAN/Internet optimization appliance that is flexible and scalable. When the network is congested, NetEqualizer’s unique “behavior shaping” technology dynamically and automatically gives priority to latency sensitive applications, such as VoIP and email.

Click here for a full price list.

Links to other bandwidth control products on the market.

Packet Shaper by Blue Coat

Exinda

Riverbed

Exinda  Packet Shaper  and Riverbed tend to focus on the enterprise WAN optimization market.

Cymphonix

Cymphonix comes  from a background of detailed reporting.

Emerging Technologies

Very solid  product for bandwidth shaping.

Exinda

Exinda from Australia has really made a good run in the US market offering a good alternative to the incumbants.

Netlimiter

For those of you who are wed to Windows NetLimiter is your answer

Nine Tips And Tricks To Speed Up Your Internet Connection


By Eli Riles
Eli Riles is a retired insurance agent from New York. He is a self-taught expert in network infrastructure. He spends half the year traveling and visiting remote corners of the earth. The other half of the year you’ll find him in his computer labs testing and tinkering with the latest network technology.  For questions or comments please contact him at
admin@netequalizer.com

Updated 3/3/2013 – We are now up to sixteen (16) tips!
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Although there is no way to actually make your true Internet speed faster, here are some tips for home and corporate users that can make better use of the bandwidth you have, thus providing the illusion of a faster pipe.

1) Caching — How  does it work and is it a good idea?

Offered by various vendors and built into Internet Explorer, caching can be very effective in many situations. Caching servers have built-in intelligence to store the most recently and most frequently requested information, thus preventing future requests from traversing a WAN/Internet link unnecessarily.

Many web servers keep a time stamp of their last update to data, and browsers such as the popular Internet Explorer will check the time stamp on the host server. If the page time stamp has not changed since the last time you accessed the page, IE will grab it and present a local stored copy of the Web page (from the last time you accessed the page), saving the time it would take to load the page from across the Internet.

So what is the downside of caching?

There are two main issues that can arise with caching:

a) Keeping the cache current. If you access a cached page that is not current, then you are at risk of getting old and incorrect information. Some things you may never want to be cached, for example the results of a transactional database query. It’s not that these problems are insurmountable, but there is always the risk that the data in cache will not be synchronized with changes. I personally have been misled by old data from my cache on several occasions.

b) Volume. There are some 100 million Web sites out on the Internet. Each site contains upwards of several megabytes of public information. The amount of data is staggering and even the smartest caching scheme cannot account for the variation in usage patterns among users and the likelihood they will hit an uncached page.

Recommended: Related article on how ISPs use caching to speed up NetFlix and Youtube Videos.

For information on turning off caching, click here.

2) Time of day does make a difference

During peak internet Usage times, 5 PM to Midnight local time, your upstream provider is also most likely congested.  If you have a bandwidth intensive task to do, such as downloading an update for your IPAD, you can likely get a much faster download by doing your download earlier in the day. I have even noticed that the more obscure YouTube’s and videos,  have problems running at peak traffic times. My upstream provider does a good job with Netflix and popular videos during peak hours ( these can be found in their cache), but if I get something that is not likely stored in a local copy on their servers the video will lag during peak times. ( see our article on caching)

3) Requesting “text-only” from your browser

If you are stuck with a dial-up or slower broadband connection, your  browser likely has an  option to load text-only. If you are a power user that’s gaming or watching YouTube, text-only will obviously have no effect on these activities, but it will speed up general browsing and e-mail.  Most web pages are loaded with graphics which take up the bulk of the load time, so switching to text-only will eliminate the graphics and save you quite a bit of time.

4) Install a bandwidth controller to make sure no single connection dominates your bandwidth.

Everything you do on the Internet creates a connection from inside your network to the Internet, and all of these connections compete for the limited amount of bandwidth your ISP provides.

Your router (cable modem) connection to the Internet provides first come/first serve service to all the applications trying to access the Internet. To make matters worse, the heavier users, the ones with the larger persistent downloads, tend to get more than their fair share of router cycles.  Large downloads are like the school yard bully, they tend to butt in line, and not play fair.

Read the full article.

5) Turn off the other computers in the house

Many times, even during the day when the kids are off to school, I’ll be using my Skype phone and the connection will break up.  I have no idea what exactly the kids’ computers are doing, but if I log them off the Internet, things get better with the Skype call every time. In a sense, it’s a competition for limited bandwidth resources, so, decreasing the competition will usually boost your computer’s performance.

6) Kill background tasks on your computer

You should also try to turn off any BitTorrent or background tasks on your computer if you are having trouble while trying to watch a video or make a VoIP call.  Use your task bar to see what applications are running and kill the ones you don’t want.  Although this is a bit drastic, you may just find that it makes a difference. You’d be surprised what’s running on your computer without you even knowing it (or wanting it).

For you gamers out there, this also means turning off the audio component on your games if you do not need it for collaboration.

7) Test your Internet speed

One of the most common issues with slow internet service is that your provider is not giving you the speed/bandwidth that they have advertised.  Here is a link to our article on testing your Internet speed, which is a good place to start.

Note:  Comcast has adopted a 15 minute Penalty box in some markets. Your initial speed tests will likely show no degradation, but if you persist at watching high-definition video for more than 15 minutes, you may get put into their Penalty box.  This practice helps preserve a limited resource in some crowded markets.  We note it here because we have heard reports of people happily watching YouTube videos only to have service degrade.

Related Articles: The real meaning of Comcast generosity.

8) Make sure you are not accidentally connected to a weak access point signal

There are several ways an access point can slow down your connection a bit.  If the signal between you and the access point is weak, the access point will automatically downgrade its service to a slower speed. This happens to me all the time. My access point goes on the blink (needs to be re-booted) and my computer connects to the neighbor’s with a weaker signal. The speed of my connection on the weaker signaled AP is quite variable.  So, if you are on wireless in a densely populated area, check to make sure what signal you are connected  to.

9) Deploy a fairness device to smooth out those rough patches during contentious busy hours

Yes, this is the NetEqualizer News Blog, but with all bias aside, these things work great. If you are in an office sharing an Internet feed with various users, the NetEqualizer will keep aggressive bandwidth users from crowding others out.  No, it cannot create additional bandwidth on your pipe, but it will eliminate the gridlock caused  by your colleague  in the next cubicle downloading a Microsoft service pack.

Yes, there are other  devices on the market (like your fancy router), but the NetEqualizer was specifically designed for this mission.

10) Kill your virus protection software

With the recent outbreak of the H1N1 virus, it reminded me of  how sometimes the symptoms and carnage from a vaccine are worse than the disease it purports to cure.  Well, the same holds true for your virus protection software. Yes, viruses are real and can take down your computer, but so can a disk crash, which is also inevitable.  You must back up your critical data regularly.  However, that virus software seems to dominate more resources on my desktop than anything else.  I no longer use anything and could not be happier.  But be sure to use a reliable back-up (as you will need to rebuild your computer now and then, which I find a better alternative than running a slow computer all of the time).

11) Set a TOS bit to provide priority

A TOS bit  is a special bit within an IP packet that directs routers to give preferential treatment to selected packets.  This sounds great, just set a bit and move to the front of the line for faster service.  As always, there are limitations.

- How does one set a TOS bit?
It seems that only very special enterprise  applications, like a VoIP PBX, actually set and make use of TOS bits. Setting the actual bit is not all that difficult if you have an application that deals with the network layer, but most commercial applications just send their data on to the host computer’s clearing house for data, which in turn puts it into IP packets without a TOS bit set.  After searching around for a while, I just don’t see any literature on being able to set a TOS bit at the application level. For example, there are a couple of forums where people mention setting the TOS bit in Skype but nothing definitive on how to do it.

- Who enforces the priority for TOS packets?
This is a function of routers at the edge of your network, and all routers along the path to wherever the IP packet is going. Generally, this limits the effectiveness of using a TOS bit to networks that you control end-to-end. In other words, a consumer using a public Internet connection cannot rely on their provider to give any precedence to TOS bits, hence this feature is relegated to enterprise networks within a business or institution.

-  Incoming traffic generally cannot be controlled.
The subject of when you can and cannot control a TOS bit does get a bit more involved.  We have gone over this in more detail in a separate  article.

12) Avoid Quota Penalties

Some providers are implementing Quotas where they slow you down if you use too much data over a period of time.  If you know that you have a large set of downloads to do, for example synching your device with iTunes Cloud, go to a library and use their free service. Or, if you are truly without morals, logon to your neighbor’s wireless network and do your synch.

13) Consider Application Shaping?

Note: Application shaping is an appropriate topic for corporate IT administrators and is generally not a practical solution for a home user.  Makers of application shapers include Blue Coat (Packeteer) and Allot (NetEnforcer), products that are typically out of the price range for many smaller networks and home users.

One of the most popular and intuitive forms of optimizing bandwidth is a method called “application shaping”, with aliases of “deep packet inspection”, “layer 7 shaping”, and perhaps a few others thrown in for good measure. For the IT manager that is held accountable for everything that can and will go wrong on a network, or the CIO that needs to manage network usage policies, this at first glance may seem like a dream come true.  If you can divvy up portions of your WAN/Internet link to various applications, then you can take control of your network and ensure that important traffic has sufficient bandwidth, right?  Well, you be the judge…

At the center of application shaping is the ability to identify traffic by type.  For example, identifying between Citrix traffic, streaming audio, Kazaa peer-to-peer, or something else.  However, this approach is not without its drawbacks.

Drawback #1: Applications can purposely use non-standard ports
Many applications are expected to use Internet ports when communicating across the Web. An Internet port is part of an Internet address, and many firewall products can easily identify ports and block or limit them. For example, the “FTP” application commonly used for downloading files uses as standard the well-known “port 21″. The fallacy with this scheme, as many operators soon find out, is that there are many applications that do not consistently use a standard fixed port for communication. Many application writers have no desire to be easily classified. In fact, they don’t want IT personnel to block them at all, so they deliberately design applications to not conform to any formal port assignment scheme. For this reason, any product that aims to block or alter application flows by port should be avoided if your primary mission is to control applications by type.

So, if standard firewalls are inadequate at blocking applications by port, what can help?

As you are likely aware, all traffic on the Internet travels around in what is called an IP packet. An IP packet can very simply be thought of as a string of characters moving from Computer A to Computer B. The string of characters is called the “payload,” much like the freight inside a railroad car. On the outside of this payload, or data, is the address where it is being sent. These two elements, the address and the payload, comprise the complete IP packet.

In the case of different applications on the Internet, we would expect to see different kinds of payloads. For example, let’s take the example of a skyscraper being transported from New York to Los Angeles. How could this be done using a freight train? Common sense suggests that one would disassemble the office tower, stuff it into as many freight cars as it takes to transport it, and then when the train arrived in Los Angeles, hopefully the workers on the other end would have the instructions on how to reassemble the tower.

Well, this analogy works with almost anything that is sent across the Internet, only the payload is some form of data, not a physical hunk of bricks, metal and wires. If we were sending a Word document as an e-mail attachment, guess what, the contents of the document would be disassembled into a bunch of IP packets and sent to the receiving e-mail client where it would be re-assembled. If I looked at the payload of each Internet packet in transit, I could actually see snippets of the document in each packet and could quite easily read the words as they went by.

At the heart of all current application shaping products is special software that examines the content of Internet packets (aka “deep packet inspection”), and through various pattern matching techniques, determines what type of application a particular flow is. Once a flow is determined, then the application shaping tool can enforce the operator’s policies on that flow. Some examples of policy are:

Limit AIM messenger traffic to 100kbs
Reserve 500kbs for Shoretell voice traffic

The list of rules you can apply to traffic types and flow is unlimited.

Drawback #2: The number of applications on the Internet is a moving target.
The best application shaping tools do a very good job of identifying several thousand of them, and yet there will always be some traffic that is unknown (estimated at 10 percent by experts from the leading manufacturers). The unknown traffic is lumped into the unknown classification and an operator must make a blanket decision on how to shape this class. Is it important? Is it not? Suppose the important traffic was streaming audio for a webcast and is not classified. Well, you get the picture. Although theory behind application shaping by type is a noble one, the cost for a company to stay up-to-date is large and there are cracks.

Drawback #3: The spectrum of application types is not static
Even if the application spectrum could be completely classified, the spectrum of applications constantly changes. You must keep licenses current to ensure you have the latest in detection capabilities. And even then it can be quite a task to constantly analyze and change the mix of policies on your network. As bandwidth costs lessen, how much human time should be spent divvying up and creating ever more complex policies to optimize your WAN traffic?

Drawback #4: Net neutrality is comprised by application shaping.
Techniques used in application shaping have become controversial on public networks, with privacy issues often conflicting with attempts to ensure network quality.

Based on these drawbacks, we believe that application shaping is not the dream come true that it may seem at first glance.  Once CIOs and IT Managers are educated on the drawbacks, they tend to agree.

14) Bypass that local consumer reseller

This option might be a little bit out of the price range of the average consumer, and it may not be practical logistically -  but if you like to do things out-of-the-box, you don’t have to buy Internet service from your local cable operator or phone company, especially if you are in a metro area.  Many customers we know have actually gone directly to a Tier 1 point of presence (backbone provider) and put in a radio backhaul direct to the source.  There are numerous companies that can set you up with a 40-to-60 megabit link with no gimmicks.

15) Speeding up your iPhone

Ever been in a highly populated area with 3 or 4 bars and still your iPhone access slows to crawl ?

The most likely reason for this problem is congestion on the provider line. 3g and 4g networks all have a limited sized pipe from the nearest tower back to the Internet. It really does not matter what your theoretical data speed is, when there are more people using the tower than the back-haul pipe can handle, you can temporarily lose service, even when your phone is showing three or four bars.

Unfortunately, you only have a couple of options in this situation. If you are in a stadium with a large crowd, your best bet is to text during the action.  If you wait for a timeout or end of the game,  you’ll find this corresponds to the times when the network slows to a crawl,  so try to finish your access before the last out of the game or the end of the quarter. Pick a time when you know the majority of people are not trying to send data.

Get away from the area of congestion. I have experienced complete lockout of up to 30 minutes, when trying to text, as a sold out stadium emptied out.  In this situation my only chance was  to walk about  1/2 mile or so from the venue to get a text out. Once away from the main stadium, my iPhone connected to a tower with a different back haul away from the congested stadium towers.

Shameless plug: If you happen to be a provider or know somebody that works for a provider  please tell them to call us and we’d be glad to explain the simplicity of equalizing and how it can restore sanity to a congested wireless backhaul.

16) Protocol Spoofing

Note:  This method is applied to Legacy Database servers doing operations over a WAN.  Skip this tip if you are a home user.

Historically, there are client-server applications that were developed for an internal LAN. Many of these applications are considered chatty. For example, to complete a transaction between a client and server, tens of messages may be transmitted when perhaps one or two would suffice. Everything was fine until companies, for logistical and other reasons, extended their LANs across the globe using WAN links to tie different locations together.

To get a better visual on what goes on in a chatty application, perhaps an analogy will help.  It’s like  sending family members your summer vacation pictures, and, for some insane reason, putting each picture in a separate envelope and mailing them individually on the same mail run. Obviously, this would be extremely inefficient, as chatty applications can be.

What protocol spoofing accomplishes is to fake out the client or server-side of the transaction and then send a more compact version of the transaction over the Internet, i.e. put all the pictures in one envelope and send it on your behalf, thus saving you postage.

You might ask why not just improve the inefficiencies in these chatty applications rather than write software to deal with the problem? Good question, but that would be the subject of a totally different article on how IT organizations must evolve with legacy technology, which is beyond the scale of the present article.

In Conclusion

Again, while there is no way to increase your true Internet speed without upgrading your service, these fourteen (15) tips can improve performance, and help you to get better results from the bandwidth that you already have.

You’re paying for it, so you might as well make sure it’s being used as effectively as possible. : )

Related Article on testing true video speed over the Internet

A great article from the tech guy regarding tips on dealing with your ISP

Other Articles on Speeding up Your Internet

Five tips and tricks to speed up your Internet

How to speed up your Internet Connection Without any Software

Tips on how to speed up your Internet

About APconnections

Created by APconnections, the NetEqualizer is a plug-and-play bandwidth control and WAN/Internet optimization appliance that is flexible and scalable. When the network is congested, NetEqualizer’s unique “behavior shaping” technology dynamically and automatically gives priority to latency sensitive applications, such as VoIP and email. Click here to request our full pricelist.

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