bandwidth – Giga thoughts …

Here is a slightly wild idea of mine

Introduction

Generally in enterprises the network bandwidth available to employees is greatest at the start of the working day and progressively becomes bad as the day progresses. The bandwidth available improves again later in the day. The reason is that the bandwidth demand is highest during the middle portions of the day usually between 10 am – 5pm when the number of employees are the highest. The poor response times during the day are common to many enterprises as the network infrastructure is stretched beyond its designed capacity

Description

This post looks at a novel technique where the increasing bandwidth is ‘outsourced’ to other geographical regions. In other words the increasing bandwidth requirement is ‘borrowed’ from the network infrastructure from other regions.

This idea visualizes the user of a network devoice (Time Zone –Traffic Director Switch) that borrows bandwidth based on the time-of-day and the bandwidth shortage in a particular region. This device effectively borrows the idle network resources (routers, hubs, switches) from other geographical regions thus resolving the bandwidth issue.

In large global organizations, office are spread throughout the world. There will be typical daytimes and night times. Night time usages will be minimal unless the office works on shifts

Large enterprises typically use leased lines between their various offices spread across the globe. Each of the regional offices will have its own set of routers, Ethernet switches, hubs etc.

The leased lines and the network infrastructure will experience peak usage during the daytime which will subside during the region’s night times. This idea looks at a scheme in which the leased line and the network infrastructure at region B are utilized during the regions’ night times to supplement the bandwidth crunch in region A’s day time

In a typical situation we can view that the enterprise’s region as the center of the network resources (hubs, routers, switches) in its own region. Simplistically we can represent this as shown in Fig 1

This post visualizes the realization of a network device namely the Time Zone-Traffic Director Switch which effectively borrows bandwidth based on the time-of-day and the bandwidth shortage in a particular region.,

This device effectively borrows the idle network resources (routes, hubs switches) from other geographical regions this resolving the bandwidth issue. Such a network device can be implemented using the Open Flow Protocol which can virtualize the network resources

In large cloud computing systems like Facebook, Google, Amazon, which have data centers spread throughout the world, traffic is directed to a data center closest to the user to minimize latency, In this scheme the use of the network resources in other geographical regions may introduce network latencies but will be economically efficient for the enterprises.

In fact this Time Zone-Traffic Director can be realized through the use of the Open Flow Protocol and Software Defined Networks (SDNs)

Detailed Description

This post utilizes a scheme in which the network resources from another are used to supplement the network resources at region during its daytimes. The leased lines and the network resources in other regions during their nights will typically experience low utilization of both the leased line capacity and the network infrastructure capacity. So in this method the bandwidth resources are borrowed from another region where the utilization of the network resources is low. This supplements the bandwidth in the region which is experiencing a bandwidth shortage. This scheme can be realized by the utilization of the Software Defined Network using the Open Flow protocol.

The Open Flow protocol has a Flow Controller which can virtualizes the network resources. This method visualizes virtualizing the network resources of a corporate office that is spread geographically around the world to optimize the corporate’s resources

This is how the scheme will have to be realized

Over dimension the leased line capacity to be at least 30%-40% more than the total capacity of it Ethernet switches gigabit routers etc. So if the network resource at a region is 16Gbps then the leased line capacity should be of the order of 20Gpbs
When an external site is to be accessed for high speed connection, after the DNS resolution the packets must be sent to the Time Zone – Traffic Director Switch
The Time Zone – Traffic Director Switch will determine the bandwidth availability at that time. Let us assume that the regional network resources are experiencing peak usage It will not decide to use the network resources of another region
The Time Zone – Traffic Director Switch will now check the time of the day. If it is the ‘regional day’ (e.g. 10 am – 5pm, when the usages is highest) it will hard code the next hop to be a router in another geographical region. SO if the traffic is to originate in Bangalore, the next hop, if there is bandwidth crunch will be in another a router in Europe, or in the US.
The Time Zone – Traffic Director Switch can be realized through th e use of the Open Flow protocol
By artificially redirecting the traffic to another region all packets will be re-routed to use the leased lines & network resources from the other region thus giving the region, Bangalore, in this case, more bandwidth

This can be represented in the following diagram

In the figure below The Time Zone – Traffic Director Switch uses the regions ‘internal’ network resources since it does not face a bandwidth crunch

In the next figure the Time Zone – Traffic Director Switch borrows the network resource from Region B

This scheme will introduce additional latency as opposed to the Shorted Path First (SPF) or the Distance Vector Algorithm (DVA) However the enterprise gets to use its network infrastructure more effectively. This will result in the enterprise’s network infrastructure to be used more efficiently and effectively reducing the CAPEX and OPEX for the entire organization.

The entire scheme can be represented by the flow chart below

Conclusion

The tradeoff in this scheme is between the economics of reusing the network and the leased line infrastructure of the enterprise versus the additional latency introduced

However the delay will be more than compensated by the increase in the bandwidth available to the end user. This idea will simultaneously solve the problem of the bandwidth crunch while efficiently and effectively utilizing the network resources across the entire enterprise. This scheme will also reduce the organization CAPEX and OPEX as resources are used more efficiently.

Thoughts?

Find me on Google+

Published in Telecom Asia, Jan 11,2012 – Technological hurdles – 2012 and beyond

You must have heard it all by now – the technological trends for 2012 and the future. The predictions range over BigData, cloud computing, internet of things, LTE, semantic web, social commerce and so on.

In this post, I thought I should focus on what seems to be significant hurdles as we advance to the future. So for a change, I wanted to play the doomsayer rather than a soothsayer. The positive trends are bound to continue and in our exuberance we may lose sight of the hurdles before us. Besides, “problems are usually opportunities in disguise”. So here is my list of the top issues that is facing the industry now.

Bandwidth shortage: A key issue of the computing infrastructure of today is data affinity, which is the result of the dual issues of data latency and the economics of data transfer. Jim Gray (Turing award in 1998) whose paper on “Distributed Computing Economics” states that that programs need to be migrated to the data on which they operate rather than transferring large amounts of data to the programs. In this paper Jim Gray tells us that the economics of today’s computing depends on four factors namely computation, networking, database storage and database access. He then equates $1 as follows

One dollar equates to

= 1 $

≈ 1 GB sent over the WAN

≈ 10 Tops (tera cpu operations)

≈ 8 hours of cpu time

≈ 1 GB disk space

≈ 10 M database accesses

≈ 10 TB of disk bandwidth

≈ 10 TB of LAN bandwidth

As can be seen from above breakup, there is a disproportionate contribution by the WAN bandwidth in comparison to the others. In others words while the processing power of CPUs and the storage capacities have multiplied accompanied by dropping prices, the cost of bandwidth has been high. Moreover the available bandwidth is insufficient to handle the explosion of data traffic.

In fact it has been found that the “cheapest and fastest way to move a Terabyte cross country is sneakernet (i.e. the transfer of electronic information, especially computer files, by physically carrying removable media such as magnetic tape, compact discs, DVDs, USB flash drives, or external drives from one computer to another).

With the burgeoning of bandwidth hungry applications it is obvious that we are going to face a bandwidth shortage. The industry will have to come with innovative solutions to provide what I would like to refer as “bandwidth-on-demand”.

The Spectrum Crunch: Powerful smartphones, extremely fast networks, content-rich applications, and increasing user awareness, have together resulted in a virtual explosion of mobile broadband data usage. There are 2 key drivers behind this phenomenal growth in mobile data. One is the explosion of devices-smartphones, tablet PCs, e-readers, laptops with wireless access. The second is video. Over 30% of overall mobile data traffic is video streaming, which is extremely bandwidth hungry. All these devices deliver high-speed content and web browsing on the move. The second is video. Over 30% of overall mobile data traffic is video streaming, which is extremely bandwidth hungry. The rest of the traffic is web browsing, file downloads, and email

The growth in mobile data traffic has been exponential. According to a report by Ericsson, mobile data is expected to double annually till 2015. Mobile broadband will see a billion subscribers this year (2011), and possibly touch 5 billion by 2015.

In an IDATE (a consulting firm) report, the total mobile data will exceed 127 exabytes (an exabyte is 1018 bytes, or 1 mn terabytes) by 2020, an increase of over 33% from 2010).

Given the current usage trends, coupled with the theoretical limits of available spectrum, the world will run out of available spectrum for the growing army of mobile users. The current spectrum availability cannot support the surge in mobile data traffic indefinitely, and demand for wireless capacity will outstrip spectrum availability by the middle of this decade or by 2014.

This is a really serious problem. In fact, it is a serious enough issue to have the White House raise a memo titled “Unleashing the Wireless Broadband Revolution”. Now the US Federal Communication Commission (FCC) has taken the step to meet the demand by letting wireless users access content via unused airwaves on the broadcast spectrum known as “White Spaces”. Google and Microsoft are already working on this technology which will allow laptops, smartphones and other wireless devices to transfer in GB instead of MB thro Wi-Fi.

But spectrum shortage is an immediate problem that needs to be addressed immediately.

IPv4 exhaustion: IPv4 address space exhaustion has been around for quite some time and warrants serious attention in the not too distant future. This problem may be even more serious than the Y2K problem. The issue is that IPv4 can address only 2^32 or 4.3 billion devices. Already the pool has been exhausted because of new technologies like IMS which uses an all IP Core and the Internet of things with more devices, sensors connected to the internet – each identified by an IP address. The solution to this problem has been addressed long back and requires that the Internet adopt IPv6 addressing scheme. IPv6 uses 128-bit long address and allows 3.4 x 1038 or 340 trillion, trillion, trillion unique addresses. However the conversion to IPv6 is not happening at the required pace and pretty soon will have to be adopted on war footing. It is clear that while the transition takes place, both IPv4 and IPv6 will co-exist so there will be an additional requirement of devices on the internet to be able to convert from one to another.

We are bound to run into a wall if organizations and enterprises do not upgrade their devices to be able to handle IPv6.

Conclusion: These are some of the technological hurdles that confront the computing industry. Given mankind’s ability to come up with innovative solutions we may find new industries being spawned in solving these bottlenecks.

Find me on Google+