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You can’t be too rich, too thin, or have too much Internet bandwidth

Videoconferencing, large video files, enterprise synchronization, public cloud computing all will contribute to the need for a lot more bandwidth

As we move into the era of the cloud, and further into the era of BYOD and the explosion of personal/consumer use of the Internet as a fundamental expectation of individual workers and their devices, having much more bandwidth at each enterprise location will be critical to the efficiency of enterprise IT. Yet I also believe that this topic is rarely given the consideration it is due. So let's continue to look at the reasons why the Enterprise WAN is going to need a lot more Internet bandwidth if it is to keep up with the reality of IT use and needs – both directly for the business and for the communications needs/expectations of enterprise users.

Last time, we saw that most enterprises have very little bandwidth, especially at remote sites, where not only on a per-user basis, but also overall there is frequently less bandwidth than the average person has at their home, or perhaps even their phone. At the same time, bandwidth demands from the explosion of BYOD and the consumer synching technology used by most of these devices, combined with the "ordinary" increase in web access by employees using traditional desktops/laptops, is leading to a huge, more than an order of magnitude increase in Internet bandwidth consumption versus just a few years ago. And this is on top of any ordinary increased demands for intranet bandwidth that have occurred for business applications, even if WAN Optimization has minimized the hiccups that might occur here from data center consolidation.

Historically, backup has consumed a fair amount of WAN bandwidth. WAN Optimization technology – and better backup software – can hugely reduce the amount of bandwidth consumed by backups. Backups for remote locations with relatively little bandwidth can essentially be eliminated altogether by the use of distributed/replicated file services, as we've covered previously. Such services are the enterprise equivalent of DropBox and similar technologies discussed last time, and can hugely improve application performance for any file-based application, and deliver true LAN-speed performance. Over very thin WAN pipes it probably does not make sense to use such file services on your enterprise WAN, but with even moderately sized WAN links, it often does. That said, as file sizes get larger, the maximum performance and efficiency gains from such replicated services come when there is even greater downstream bandwidth available at smaller locations, to do the continuous "pre-positioning" of files that is the nature of such synchronized, replicated services.

Perhaps the greatest demand on enterprise bandwidth over the next several years will come from video. Video will consume large amounts of bandwidth in three separate ways. Videoconferencing consumes a fair amount of bandwidth. Low-resolution video requires anywhere from 256 Kbps to about 700 Kbps per session. High-definition video requires at least 1 Mbps, and might consume more than that.

Streaming video can require similar amounts of bandwidth depending on resolution. Whether for business purposes or not, more and more streamed video will no doubt enter your network, and in many cases it will not be easy to tell which video is for personal use and which is for the business. Video files exchanged within the enterprise and stored on individual machines or servers can be orders of magnitude larger than other file types.  Whether via email, ordinary file access, or replicated file service as noted above, these kinds of video files, such as those used for training, will consume large amounts of bandwidth whenever they are transferred - including when they are replicated.

Finally, there is the issue of SaaS and public cloud computing. While such applications are usually web-based and often require less bandwidth than earlier generation "fat" client-server applications, when based in the cloud, the user connections are typically encrypted using the HTTPS protocol rather than unencrypted HTTP. This means that web caches and WAN Optimization's compression and deduplication technologies cannot reduce the bandwidth consumed. If, for example, your organization switched to HTTPS-based Gmail or hosted Exchange for email, then a branch with 10 employees who each receive the same 1 GB attachment will see that file downloaded 10 times, rather than have the data only traverse the WAN once.

Other than for externally-based HTTPS applications, for the clear majority of enterprise shops that backhaul their Internet access to headquarters or a data center, WAN Optimization can and does help with bandwidth issues for remote locations somewhat, but it can only do so much to improve the effective capacity of a 1.5 or 2 (or 3 or 4) Mbps link. If you purchased your WAN Optimization solution 18 or more months ago and were able to avoid a bandwidth upgrade then, you have probably already seen WAN bandwidth demands increase just from internal uses alone. And because MPLS is so expensive, addressing bandwidth problems by purchasing a lot more MPLS bandwidth is almost never a viable alternative.

So we see that the demand for bandwidth for a wide variety of applications, many if not most of which are Internet-based, is driving and will continue to drive enterprise bandwidth needs up dramatically for the next several years. Next time, we'll look more closely at the performance, security and ease of management issues involved with how enterprise Internet access is done today, with an eye towards how these issues, as well as the issue of Internet bandwidth, can be addressed with the Next-generation Enterprise WAN (NEW) architecture.

A twenty-five year data networking veteran, Andy founded Talari Networks, a pioneer in WAN Virtualization technology, and served as its first CEO, and is now leading product management at Aryaka Networks. Andy is the author of an upcoming book on Next-generation Enterprise WANs.

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