Bharti results

Bharti has posted strong Q4 results on the back of “rural penetration and customer affordability”. Several articles discuss this like this one at yahoo. The official press release from Bharti is here.

What is broadband?

“Broadband” is a term that has percolated into every day vocabulary and the layman understands that it is the service that allows access to the internet. People who have memories of previous dialup access methods also understand that this is a faster means of access to the internet.

Originally in radio telecommunications, bandwidth referred to the difference in the lower and higher cutoff frequencies for a communications channel. Narrowband communications referred to operating in a regulation defined small range of frequency bands using low bandwidth applications while wideband communications are high on bandwidth and operate in a larger range of frequency bands. Very often, wideband is replaced with the word broadband, indicating that a high bandwidth communication is possible.

In data communications, transfers at speeds over 56 kbps (kilobits per second) are defined as broadband communications with the actual speed a subject of in-country regulation.  For example, the US FCC in 2008 defines speeds above 756 kbps to be broadband whereas in India the broadband policy of 2004 defines broadband as:

An ‘always-on’ data connection that is able to support interactive services including Internet access and has the capability of the minimum download speed of 256 kilo bits per second (kbps) to an individual subscriber from the Point Of Presence (POP) of the service provider intending to provide Broadband service where multiple such individual Broadband connections are aggregated and the subscriber is able to access these interactive services including the Internet through this POP.

Various access network technologies can be used to provide broadband services:

• DSL (Digital Subscriber Line) uses existing copper infrastructure that was already being used for voice telephony and with improvements in the technology over the years offers good bandwidth and QoS (Quality of Service).  It is considered as one of the most economical options as it reuses existing infrastructure and is especially useful in regions of high population density.
• Fibre technologies offer a quantum improvement in bandwidth over DSL but require the laying of new optical fibre infrastructure and hence is heavy on CAPEX.  Telcos tend to prioritize the fibre rollout, initially using it for their own interconnect infrastructure and subsequently rolling out last mile fibre incrementally in their areas of operation.
• Cable technologies have transformed from a unidirectional TV medium to one that can offer bidirectional data services at broadband speeds.  In certain regions of the globe it is the predominant broadband access technology.
• Broadband wireless technologies like WiMAX, femto, CDMA EVDO (Enhanced Version Data Only) are gaining ground.  EVDO data cards offer the additional convenience of supporting mobility via the CDMA network and are popular with roaming users.  Fixed WiMAX and femto are seeing initial deployments in niche regions as a suitable alternative in greenfield areas to the more expensive fibre.

The Broadband Forum is the primary industry body and works on specifications to accelerate the development of broadband networks. A noteworthy point is that the Broadband Forum started life as the DSL Forum, went on to increase focus to include Fibre technologies. It liases with several other forums like the WiMAX Forum, MPLS Forum, Metro Ethernet Forum and ITU-T.

In India, TRAI publishes statistics on broadband subscriber growth – the most recent release indicates that there are 6.22 million broadband subscribers as of March 2009. TRAI also provides guidelines to the ISPs on improving QoS (Quality of Service) of broadband services. A recent guideline discusses the maximum contention ratio (number of customers sharing defined bandwidth) as 1:50 for residential and 1:30 for business users.

Wikipedia is your friend for more information:

Broadband Internet Access

Broadband

What is AAA?

AAA stands for three aspects that are very important in a telco perspective:
- Authentication: The means by which an end user establishes who he is and informs the network that he is using the network. In the GSM (Global System for Mobile) world this is established via the details on the SIM (Subscriber Information Module) in the handset and in the wired networks, for instance where DSL (Digital Subscriber Line) modems are used this is via the username and password that the person configuring your DSL connection setup during the first install (or what you subsequently changed it to).
- Authorization: This refers to the end user rights on the network and is established subsequent to the authentication. This basicallyindicates the kind of services that an end user has subscribed for and is entitled to once he successfully authenticates himself. In the mobile world this could be in terms of basic voice services and the list of VAS (Value Added Services) subscribed to. As an illustration, the pre-paid customer whose balance has run out is entitled only to incoming calls and no outgoing calls. An example from the wired services could be the bandwidth subscribed for by the user.
- Accounting: Tracking of network resource usage by the user. This could be in terms of number of calls and duration or in terms of megabytes of data transferred etc.

The telco uses well established protocols to implement AAA. The need for standards in this area is due to the multiple systems that interface – the end user device connecting with the access gateway at the telco and then to other systems to use specific services. The original AAA protocol that has stood the test of time is RADIUS (Remote Authentication Dial In User Service). It has been standardized by IETF (Internet Engineering Task Force) in the nineties. As the name suggests, it was first used for authentication in dial-up access services but has found its place in both wired and wireless networks to satisfy the AAA functionality. Subsequently, the Diameter protocol was defined during this decade and continues to evolve. Diameter is not an acronym, but just a play on the language indicating a protocol that is twice as good as RADIUS. However, Diameter is deployed only for specific niche applications and yet needs to see mainstream deployment.

The seminal references on these protocols are of course, the IETF web pages:
DIME is the ongoing work on Diameter
RADEXT discusses the extensions to RADIUS

For more generic reading, Wikipedia is your friend
AAA
RADIUS
Diameter

PS This is hopefully, the first of an ongoing series to describe technology in simplistic terms.

Remembering first principles

As I am a computer science student who meandered into telecom as an application area (more due to circumstance than intent), I plan to refresh my basic principles once in a while. One of the seminal articles on sound principles for system programming has been published by ACM as far back as 1969. I think that systems engineers should re-read this article every few years to remind themselves of what should be vs what is. As I re-read it currently, the applicability to telecom systems – whether they be networks, services, OSS/BSS systems – clearly surfaces.

In brief, the article lists the fundamental principles of good systems programming (includes aspects like forgivingness and monitorability in addition to the well-known ones like modularity and availability) and defines all of them. It then goes on to discuss the problems that come in the way of adhering to the principles followed by cost metrics for systems. I think the cost metrics concept is something very important for software deployment, more so for telecom systems deployment. The article then discusses higher level implementation languages (remember that this was written in 1969 when handcoding in machine language was the order of the day. The parallel to modern day systems would be usage of meta-systems like application middleware or service delivery platforms in the telco world).

The article includes some good external quotes as well as creates its own quote-worthy statements like:
There is no substitute for intelligent forethought and coordinated planning using the principles of good engineering and development management. (T. J. Watson)

We don’t read. Very few system developers are familiar with work done outside of their own project.

PS Thanks to the NANOG poster who quoted from this and reminded me to re-read this gem.

NSN Nortel deal?

Most analysts are buzzing about NSN as the prospective buyer of Nortel mobile assets seeking to challenge ALU in the CDMA market while grabbing the existing Nortel customer base. See Reuters article from last week and an article from telecom magazine earlier this month.

Financial watchers have reported on NSN seeking credit speculating that it might be for the acquisition

In the meantime Nortel has filed for extending its bankruptcy protection till July 30 (was due to expire at the end of April).

BTW, info on all one ever wanted to know about Nortel is available at All about Nortel.

Accidental subscription of VAS

TRAI has issued a new directive for transparency on VAS subscriptions that aim to protect the consumer from any half-baked intentions or the lack of understanding that the simple suggestion to “Press * to copy caller tunes” results in a charge on the next bill. Now, explicit consent via “SMS or fax or email” is to be obtained and acceptance of charge via pressing keys during pre-call or ring back is forbidden.

I don’t see the mobile providers rushing to implement this one (just like the January 2009 mandate stating that hard copy summary bills should be made available for post-paid customers who request for it) but they do have a clock ticking – 45 days for implementation.

India mobile subs

Much has been written about the explosive growth of mobile subscription in India.  As per current TRAI reports , we are nearing the 400 mill mark.  However, the TRAI official classification includes FWP or WLL along with the GSM and CDMA nos.

At the same time, rural teledensity has been a subject of concern (12.59 in rural vs 81.38 in urban per 100 of population).  Last month, TRAI had issued recommendations on accelerating growth of rural telephony which listed improvements on the USOF (Universal Service Obligation Fund) subsidy including trials involving existing post offices as points of sale with  several suggested improvements in the infrastructure setup.  As per the USOF website, mobile infrastructure is already under development and services under the scheme was scheduled for late last year (I am looking for data on such services, will update subsequently).

It remains to be seen whether there will be a significant impact via such initiatives.

Hello world!

Having experienced the telecom industry both from within and as a consumer, it is time to start airing views on the aspects that impact me.  This is the starting point.