By: Jason Brunk
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We have all seen the great videos from co-workers.  The “Dramatic Ground Hog“, the Star Wars kid, the badgers song and the laughing baby.  These are great entertainment.  But have you ever thought of the impact of those videos on your corporate network?

What impact could that streaming video have?  The impact can be seen by your friendly IT department.  The impact is the bandwidth used by that video.  It may not seem like a lot, but can quickly add up when you send that same video to everyone in the company.   Example:

1 Video of Dramatic Ground Hog = 1.5 Megs

Now, you think it’s hysterical.  So would everyone else.  You send it out.  Now you have 55 people in the company all receive it at around the same time.  Because we all now watch our email like hawks, most of us will try to go to it right then.  Total Bandwidth in very short amount of = 82.5 Megs.  Our current network has a 10 megabit pipe to the Internet, but most companies may have 5 megabits.  This 82.5 megabit rush is not a huge issue, however it still has an impact..    At FULL capacity our line can do 1.25 megabytes per second.  Full capacity is only theoretical and never happens.  There is normal overhead of network traffic, existing connections, etc.  This small rush of this one little video would completely tie up the entire internet connection for 66 seconds or longer. 

That’s only a minute!!!!!!  You are correct, if you work in IT, you know it takes only about 15 seconds of outage for someone to notice and start asking about it.  So what happened?  That 1 viral video of the Ground Hog you don’t want to cross paths with could very easily tie up the line for minutes at a time.    .  What happens if you are giving a demo to a large customer in your conference room and you can’t get to a website?

How does IT combat this barrage of Menacing Ground Hogs?  Easily, a cache server.

On our network we employ a Squid Cache server.  This is a server that just sits on the network talking back and forth with the Cisco Router.   Using the WCCP version 2 protocol , the 2 talk to each other and when a request comes through the router heading to a website, the router steps in and says “hold up, I am going to see if the cache server over here already has what you are looking for.”   The router redirects the request to the cache server.  If the cache server has the requested info, it hands it back to the user directly.  If it does not, it goes out, gets the data, saves it, and then hands it to the user.  How does the benefit us in the battle of Ground Hogs?   First person to go to the site and watch the video requests it through the cache server.  Once its there, each subsequent request is handled locally be the cache server.  Another great thing about WCCP is it allows for a Fail-Open architecture.  Most cache servers are in-line in architecture.  In-Line means that all traffic physically flows through the cache server to get to the outside.  If the cache server is down, then no traffic can get out.  A reboot or server outage can be catastrophic in this architecture.  A Fail-Open architecture means that if there is a failure of the cache server that all traffic will still be able to flow to the internet.  WCCP protocol is also completely transparent to users.  It is implemented on the router so no changes to the client are required to make it work.

Conclusion:  Viral videos are funny and are definitely good entertainment.  But can easily cause issues on the network just like streaming.  IT has tools such as Squid to help in the battle against Dramatic Ground Hogs…..