Subscribe

Cache is king

Can Web caching services alleviate SA's mobile bandwidth capacity constraints?

Dieter Küsel
By Dieter Küsel, Contract manager at ZTE.
Johannesburg, 13 Jun 2017

With long-term evolution (LTE) being rolled out by SA's mobile operators, and the arrival of 5G reputed to be coming in the foreseeable future, there still seems to be a current constraint on bandwidth capacity for the increasing number of mobile Internet users in SA.

This country differs from developed countries, as the majority of the population here does not have the privilege of fixed-line broadband Internet. They therefore must rely on mobile data to access the World Wide Web, and in so doing, become part of the global information age.

According to We Are Social, as of January 2016, 92% of adult South Africans were accessing the Web via their mobile phones, of which 60% were using smartphones. It was further stated just fewer than 50% of SA's entire population, about 26.84 million, are active Internet users. The numbers will undoubtedly grow going forward, causing the demand for bandwidth to grow exponentially, with more bandwidth-hungry digital media becoming available on the Web.

To cache or not to cache

I suspect this is probably the main driver for mobile operators to increase bandwidth capacity and increase download speeds on their networks. Until such time as the mobile operators are able to catch up with the demand, the question is whether or not Web caching - defined as the temporary storage of Web documents to reduce bandwidth usage and more - can, in the interim, alleviate some of the constraints.

This is an era where faster access to information is almost a necessity.

After all, this is an era where faster access to information is almost a necessity. So, if users don't get instant gratification, they may very well go to the next site to get what they want. This has a knock-on effect on the potential revenue sources for Web advertisers. Mobile operators could also potentially lose subscribers to their competitors if they are not able to meet their customer demands. Mobile operators will have to adapt and implement some form of temporary or interim solution to alleviate subscriber frustration.

Users of the Internet are probably all aware of the normal local caching that gets done on their devices, like a smartphone or laptop, where a click on the 'back' button goes back to the previous Web page. This is done via the cache on the device, and not a Web caching server.

IT experts advise clearing the cache on personal devices to prevent them from becoming too slow. Clearing the cache will delete the temporary files, documents, etc, that were accessed. The length of time these files will be stored on a device depends on the settings on the device. This can be made shorter or longer, depending on the user's preferences, and should ideally be determined by how much browsing is done versus the storage capability on the device. If one has limited capacity, the duration should be shortened to avoid the hard drive reaching full capacity too quickly.

One possible solution for network operators could be the implementation of their own Web caching services on their networks. Web caching, also known as HTTP caching, is a technology where documents or pages from the Internet are stored temporarily. This allows for faster access the second time round, and thereby reduces bandwidth usage and the load on the Web servers where the information is stored. This results in a better user experience. It is similar to the caching being done on a local device hard drive.

In other words, a Web cache system stores copies of documents or even images passing through it, resulting in any subsequent requests being accessed from the cache, if certain conditions are met.

Legally speaking, providers and operators of a Web caching system or service have certain obligations that must be met in order not to attract legal liability. Web caching is regulated by section 74 of the Electronic Communications and Transactions Act, 25 of 2002. Section 74 of the Act essentially requires a provider or an operator that transmits data provided by a party from whom the data has been received along an information system under its control, cannot be held liable for the automatic, intermediate and temporary storage of that data, where the purpose of storing that data is to further transmit the data and thereby make it more efficient to other recipients of the service on their request.

However, this is qualified by the following constraints. The service provider must:

* Not modify the data;
* Comply with conditions on access to the data;
* Comply with rules regarding the updating of the data, specified in a manner widely recognised and used by industry;
* Not interfere with the lawful use of technology, widely recognised and used by industry, to obtain information on the use of the data; and
* Remove or disable access to the data it has stored on receiving a take-down notice referred to in Section 77 of the Act.

In other words, as long as the operator complies with the conditions in the Act, it cannot be held liable for storing information or data without the owner's permission, provided it ensures there is still adherence to the owner's rules of accessing the material, for example, accessing it with a username and password.

Share