Repeat after me: “IPv6 is my friend”! And keep that up because it´s true! But I´m not going to formally introduce you to all its benefits just yet because going there would turn this blog into a full-fledged article. I´ll be going there really soon though, so stay tuned! For now, just know that IPv6 will be a hugely important part of your future, and let me continue my rave on why using Vista and Server 2008 are going to do great things for your networking career.

In my last post I discussed chimney and receive side scaling—stuff that new multiple processor servers are likely to come with. So now I want to move on to telling you about how the new stack provides optimization on both the receiving and sending sides for the hosts on your network. I´ll finish up by telling you why on earth all this Microsoft stuff I´ve been chattering about in these two posts is so very strangely important to you as a Cisco network admin! Here´s a couple good reasons:

Receive Window Auto-Tuning and Compound TCP (CTCP).

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• Receive window auto tuning optimized receiver-side throughput and upgrades the old TCP Windowing we used for receive flow control. This little beauty will allow us to have very large MTU´s.
• CTCP optimizes sender-side throughput and is most noticeable in high-latency, long round-trip time (RTT) networks (like wireless and cellular, or inter-continental links).

Receive Window Auto Tuning is enabled by default on both Vista and Server 2008 and CTCP is only enabled on Server 2008. Personally, at least right now, I see no reason not to enable CTCP on all your hosts, but Microsoft doesn´t advise doing this for some as yet unknown reason.

Okay, before I get to describing the good news part of all this Microsoft stuff, I need to explain something first: Receive Window Auto Tuning tries to send so much data so quickly that you can often watch network problems pop up as fast as noxious weeds. We´ve all heard multitudes howling about Vista creating wide variety of evils, so I´m pretty sure we´ll hear even more complaints as Server 2008 rolls out. But the thing is, it´s actually not Vista´s fault, or even Server 2008´s fault. Nope—it´s your fault! Why? Simple… You need to upgrade your network. This is the part I love about Vista and Server 2008, and it´s also the reason I´m writing a blog about Microsoft on my Cisco training web site! I see this as a true opportunity and so should you—an opportunity to get certified in these things so you will be poised, ready and able to cure the broken networks epidemic we´re about to experience!

Say you´re not surprisingly having problems with your network going up/down, application unreliability, on-line storage problems, and other disturbingly weird issues after you installed Vista. Steel your nerves and resist the temptation to revert back to XP—it´s not your solution. Yes, you can temporarily disable receive window auto tuning, but remember, if you do this, you´re pretty much satisfied with saying “I have a network issue that I can solve temporarily by disabling receive window auto tuning—viola!” You don´t want to do this permanently because it´s total denial, (which is unhealthy), and worse, it prevents you from accessing and enjoying all the bennies that new networking stack has waiting for you! Instead, roll up your sleeves, toss out the crate of tissues and: Upgrade your network to gigabit links for your hosts and switch ports as well as all your router interfaces add ten gig links and TOE cards with RSS capability for your servers, then watch your network rock the house! Oh, and don´t forget to take a (gracious) bow and accept that promotion! The new networking stack can optimally make use of all this bandwidth wealth. The older stack just didn´t have what it takes—it just was not smart enough to understand how to take advantage of it. Interestingly, this means bottlenecks will no longer clog at our hosts and servers, but on our network interfaces and routers instead.

I was in the U.K. last week and came across some fascinating facts: I read that there simply are “not enough certified network individuals with enough network experience and so, it´s estimated that by 2012, the Internet in the U.K. cannot exist as it currently does. For the U.S. that time frame is only slightly extended to 2015”. So basically, in order to keep enjoying our precious internet, we have no choice but to fully embrace the new networking stack and we need to get our networks upgraded, and do so ASAP! Sure, you can disable most of the features to make your networks work temporarily, but call me odd—is it really a solution if it means losing a proven 40 to 400% increase in throughput on your network when with a just few adjustments you´re good to go with the new networking stack instead? Do you really think that you can force your company to stay with XP forever? Sheesh… I remember many companies telling me that they would never consider using wireless networks! HA! That´s laughable today, although sure, I do know some super-high security networks that still don´t allow wireless, but can you imagine a network that exists completely without it? Probably not—at least very rarely and they´re definitely not the norm. In 5 years, it´ll be the same situation regarding IPv6 and Windows 7, due out in 2010 (which means 2011).

So to sum things up, take my advice and make sure you understand how to configure a Cisco router and switch, how to upgrade your network ports to gigabit, and how to implement TOE boards with receive side scaling support on your servers. Get Cisco certified and start planning this migration/network upgrade now; it could save your job!

Oh… Just this one last thought: The top ten jobs of 2015 haven´t even been created yet, and in as little as five years, you´ll be running products on your network that are now just a twinkle in their inventor´s eye! Where and how successfully you´ll fit into this future directly and completely correlates to how well you position yourself for these changes now! Stay current—stay ahead, and best of luck to you.

Cheers!

Side note:
To disable Receive Window Auto-Tuning: netsh interfacetcp set global autotuning level-disabled
To enable CTCP on Vista: netsh interface tcp set global congestionprovider=ctcp