With the introduction of the next-generation technologies and the growing penetration of smartphones, service providers are witnessing heavy traffic load on their networks. To meet the increasing demand of higher bandwidth, operators are making significant investments to revamp their backhaul infrastructure. However, transition to all IP and fibre-based backhaul poses several technological and operational challenges. tele.net talks to industry experts about the trends in the Indian backhaul market…

How have operators’ backhaul network requirements evolved over the past few years? What are the key growth drivers for the backhaul market in India?

Pankaj Agrawal

Currently, the majority of the country’s telecom network is based on microwave backhaul. With spectrum liberalisation, operators looking to use the GSM band to offer 3G services and the planned deployment of long term evolution (LTE) services on the 1800 MHz band, and the industry could witness higher data demand on the aggregate side, which will subsequently drive up the demand for backhaul.

So far, the fibre-to-microwave ratio in a telecom operator’s backhaul network in metro and Tier 1 markets has been 1:5. This implies that for every five sites connected on microwave, only one is on fibre. Now, this ratio has started shifting to 1:2, particularly for large operators, several of whom have started migrating their metro backhaul to fibre. However, there has not been any major development on the operators’ part to connect every tower with fibre as players are adopting a selective approach while upgrading their backhaul.

Benoy C.S.

In India, backhaul support is provided using microwave links; while the core, metro and aggregation networks use fibre, about 80 per cent of the overall backhaul network is based on microwave links.

India witnessed a telecom revolution in the past decade and half and since this growth was voice centric, microwave backhaul was adequate to support it.  However, with next-generation technologies being deployed in the country, the sector is awaiting the next phase of growth, which will be data centric. And to support this growth, operators will require an efficient and robust mobile backhaul network. With the industry now focusing on data and user experience, operators will increasingly look to move towards an all-IP-based backhaul.

Growing smartphone penetration along with the increased adoption of bandwidth-intensive devices and services will result in exponential data growth. Further, LTE is expected to facilitate the adoption of data-intensive applications. Therefore, it is important that operators upgrade their legacy networks to make them robust enough to handle the data deluge.

Sameer Dave

Operators have always recognised the need to increase backhaul bandwidth to meet the growing voice and data demand of the subscribers. Earlier, this demand was in line with the adoption of 2G and 3G services by consumers and prompted operators to upgrade their existing infrastructure to 3G. Today, aligned with the evolution of the consumer demand for data and new technologies, operators are required to upgrade their existing backhaul networks as they deploy LTE/4G to support higher data speeds and payloads. Going forward, data growth and upgradation to newer technologies will largely drive the backhaul market in India.

What are the key reasons for the low fibre deployment in India? How do you see the microwave-fibre backhaul mix changing, going forward?

Pankaj Agrawal

Even with increasing demand for data usage, the industry is unlikely to witness major changes in the backhaul mix because the capability of microwave backhaul is improving. As per industry estimates, microwave backhaul links are capable of supporting up to 200 Mbps of data on an average. Over the next two to three years, traffic on per-operator basis is unlikely to go beyond 200 Mbps. In fact, operators will require higher capacity on their networks only after they have access to spectrum in the 700 MHz band.

Currently, operators are introducing fibre in the top 25 cities and are looking to expand their reach. Unless the industry has a large chunk of spectrum on the access side, the demand for backhaul is unlikely to increase.

Further, operators in India are still not open to backhaul sharing, and are reluctant to share their fibre-based infrastructure due to concerns related to losing the competitive advantage over other players.

Benoy C.S.

So far, fibre deployment in India has been limited as its installation is expensive and involves several challenges, especially in metros and cities. Securing right-of-way (RoW) has been the single biggest hurdle and as a result, the dependence on microwave backhaul has increased over time.

Sameer Dave

Microwave has been a major part of the backhaul deployment by operators in India. It can be observed that fibre deployment has been carried out only in major routes and the primary reasons for this have been high upfront capex and RoW issues. As a result, most urban and suburban areas still do not have access to fibre bandwidth.

Going forward, operators will have to start deploying hybrid microwave and fibre in secondary routes and connect as many sites as possible on fibre to meet the required bandwidth and latency requirements. Fibre penetration will improve with the introduction of LTE-based networks.

What are the key challenges faced by operators in upgrading their backhaul networks or migrating to all-IP networks?

Pankaj Agrawal

Operators do not face any technology challenges while migrating to all-IP networks. The equipment cost for establishing an all-IP network is much lower than that associated with a time division multiplexing (TDM)-based network. In fact, there are issues related to the roll-out of fibre, particularly in securing RoW clearances.

Sameer Dave

At present, the telecom requirements of rural masses are being supported on microwave due to the low demand for telecom services in these areas. However, we have already witnessed a rise in data uptake and as the consumer demand evolves, coupled with higher mobile and internet penetration, operators will upgrade their backhaul.

Other challenges for operators will be related to frequency interference, no line-of-sight and larger hop distances. They will also have to replace their legacy transmission equipment, which does not support IP. Therefore, operators will have to undertake new transport planning to make migration to an all-IP network successful and cost effective. “IP-fication” of both legacy and next-generation radio equipment is necessary to move to pure-IP backhaul play.

What are some of the backhaul upgradation and deployment strategies that the operators are likely to adopt with the introduction of 4G/LTE services in the country?

Pankaj Agrawal

Going forward, the quantum of spectrum available for LTE services will determine or impact the mix of backhaul technologies deployed by operators. Operators’ backhaul mix will not change significantly unless spectrum availability for offering LTE services improves.

Operators will increasingly opt for an all-IP backhaul while upgrading their existing infrastructure.

Benoy C.S.

While upgrading existing legacy networks, it is important to note that technologies like 2G, 3G and LTE will co-exist. While LTE is purely data, 2G and 3G support voice as well. Therefore, there is a need to have a hybrid TDM/Ethernet platform to carry voice as well as data traffic.

Going forward, the focus will be on deploying hybrid or all-IP network equipment in the transmission segment. In urban areas, the focus will be on providing fibre-to-the-x, wherein “x” can be home, neighbourhood, desktop, etc., since these customers will register high usage of triple-play services.

The strategy adopted has to factor in issues like the total cost of ownership, technology and network complexity.

Sameer Dave

The adoption of new technologies has increased an operator’s focus on backhaul network upgradation. Options that service providers can explore include aggressively building fibre aggregation hubs to backhaul traffic from three to five sites to central core nodes using fibre networks and intra-city fibre deployment in B-Class cities across India. Operators may also partner with each other and geographically divide the area for backhaul deployment and bring in synergy to reduce costs and time. Dark fibre leasing could be the fastest way of increasing 4G/LTE coverage and 30-40 per cent of sites in high growth centres would be fibre enabled by 2016.