Beefing Up the Lynchpin
Increasing demands of 3G & LTE call for strengthening the strained backbone network while technologies like 100G, ONT, DWDM knock at the operators’ door for investment
Increasing demands of 3G & LTE call for strengthening the strained backbone network while technologies like 100G, ONT, DWDM knock at the operators’ door for investment
Increasing demands of 3G & LTE call for strengthening the strained backbone network while technologies like 100G, ONT, DWDM knock at the operators’ door for investment
The Indian mobile consumers saw the third generation services kicking off with not much hope, yet there was too much excitement in 2011. A year after the auctions, we saw most operators rushing to serve their half cooked 3G dishes to their subscribers. The existing wireless infrastructure in India was designed to support only 2G technologies (for more voice-centric services) but with 3G, the backbone network capacity went for a toss.
The launch of 3G services stepped up the need for fiber optics infrastructure and backbone network services substantially. The growing subscriber base and the current 3G mess with demands and opportunities of fourth generation data services are further ripping the network links apart.
According to a performance indicator report released recently by Trai, the number of telephone subscribers in India increased from 885.99 mn at the end of Jun’11 to 906.93 mn at the end of Sept’11, registering a growth of 2.36%. Also, the report revealed that 42.79% of total wireless subscribers base are capable of accessing data services/internet at the end of September’11. With 42.79% of 906.93 mn capable of using the present high speed data services; it clearly indicates how much more these services will add to the pressure on the backbone network. Such exponential growth in subscribers, devices, and overall traffic leads to an inevitable impact on the network performance and service quality. With the 3G subscriber base crossing almost 14 mn within a year of its roll out, the operators are in the process of expanding the 3G reach to smaller towns as well.
The evolution of 3G, Wimax, and 4G technologies is providing the basis for rapid data uptake in mobile networks. A number of applications and devices such as smartphones and dongles have started operating at speeds of 21 Mbps and beyond, and are expected to go up to 80-100 Mbps with 4G in the near term.
Undoubtedly, 3G and BWA would require an enhanced backbone network. While the 3G services have been growing, high growth in 3G traffic is yet to happen in India. The poor quality of 3G services provided by operators also impacts the 3G uptake, the major reason being the present choked backbone network leading to low QOS, capacity constraints effecting even 2G services like call drops, etc.
Going forward, with the existing 3G networks being upgraded to LTE, HSPA+,ETC, to meet the increasing demand, the transport networks will come under strain. With further addition of 3G subscribers in coming times, the network capabilities of operators would need a drastic upgradation.
The Cramped Network
Backbone network capacity dictates the operator’s service level, the essential product of their business, and under-investing in it can lead to severe compromises in customer-visible service quality. The present backbone network, which was well suited to serve the capacity needed for voice; now caters to the demands of data services like 3G. This is resulting in network choking, congestion, and capacity constraints. The operators are busy setting up new towers, co-locating their node B sites, and tying up with other operators or IP-1 players for co-locating their node B sites. On the backbone front, operator’s investments and deployments of new technologies is, however, done in a very limited manner. Laying of optical fiber till now is being done on snail’s speed.
Idea rolled out 2,270 2G cell sites during the quarter Q3FY11, taking EOP 2G cell sites count to 80,637, while count of 3G cell sites (Node B) increased to 10,902 compared to 9,744 in Q2FY11. However,
About 10% of the network is fiberized, that too only in major cities. And 30-40% of the network is still on microwave
the company laid close to 60,000 km of fiber cable transmission network by the end of Q3FY11. In case of Bharti airtel, their Q2FY11 result shows company’s YOY growth of optical fiber network to 17,694 Rkms. By September 2011, they laid close to 151,719 Rkms. On the other hand, Reliance Communications has covered 160,000 Rkms of optical fiber network by Q2FY11.
10% of the network is fiberized, that too only in major cities. 30-40% of the network is still on microwave. In the last few years, though the operators have increased their route kilometers, but the capacity of these networks remain unaltered.
Sanjay Dhawan, vice president, Ericsson India says, “With 3G/HSPA/HSPA+ technology, the possible speeds have gone up to the level of 21 Mbps on the radio side and to cater to these level of speeds, we need to have an equivalent level of backhaul, which means 14-21 Mbps of (7 E1 to 12 E1 equivalent). With LTE, the speeds will be closer to 60- 80 Mbps, which would need backhaul of similar levels (30 E1 to 40 E1 equivalent).”
Jagbir Singh, director, network services group, Bharti airtel confirms that with 3G and LTE deployments, the backhaul requirements have catapulted by 5 to 20 times.
The present capacity can accommodate 2 to 3 times traffic jumps; but technologies like 4G, LTE, and Wimax will further shoot the capacity demands to almost 40 times.
“As traffic demands continue growing, data rates will grow beyond the current 100G,” adds Puneet Sharma, lead, optics network division, India regional unit, Alcatel-lucent.
Sameer Sinha, chief sales and marketing officer, Indus Towers explains that if we see the US market, they have wireline network in place from the beginning. They had enough copper in land due to which fiberizing this network was no big task. 3040% of AT&T sites are on fiber. Whereas if we see the Indian context, 30-40% is on microwave, opposite of the US market. No copper in ground means fiber laying is another hurdle for the operators.
Singh informs, “In addition to expanding the network into newer geographies and increasing our penetration levels in currently covered cities and towns, one major thing that also has a huge impact on the consistency of service is the resiliency of the network to unforeseen circumstances. For instance, the fiber cuts that happen in India are way above the global benchmarks. The most effective way to counter this phenomenon is to connect the critical locations through multiple paths and increase the geographic redundancy of the network and that is one of the areas where we invest our time, money, and effort.”
The industry agrees on the fact that fiber laying will give operators an unlimited capacity for their network demands for times to come; however considering the current situations, network fiberizing is at a slow pace and demands a huge investment.
Vishant Vora, chief technology officer, Vodafone India confirms, “The fiber penetration into the deeper aggregation level is being increased to have enhanced customer experience and support bandwidth augmentation on the fly. However multiprotocol label switching (IP-MPLS) and automatically switched optical network (ASON) over dense wavelength digital multiplexing (DWDM) are the technologies of choice.”
“These operators are faced with the dilemma of how to balance the existing capex with the need to introduce new services and capabilities,” insists Dr Kumar N Sivarajan, CTO, Tejas Networks. A challenge being faced when considering the backbone network enhancement is that there is more than one motivation driving the demand and investment in main transmission facilities; these are basically network reliability/redundancy and capacity.
Singh explains, “A lot of factors contribute to the decision of building a backbone, to name a few, spectrum availability, market share, a company’s strategy about the technologies they want to offer, etc. We are always looking to invest in the latest technologies to stand in line with the global standards.”
Mckeon, director, product marketing, network switch, Broadcom India agrees, “Operator networks are complex, with legacy requirements, regulations, investment metrics, and handset roll outs, all playing a part in their deployment time lines, so it is difficult for us to measure precisely how advanced these new network build-outs are.”
Enhancing Technologies
The backbone is a critical part of the 3G and BWA networks. The 2 key considerations for optical backbone planning for 3G and BWA networks relate to building/augmenting capacity in the optical backbone network to cater to the anticipated increased traffic from 3G and BWA network as well as the technology choice for meeting the changing traffic mix towards Ethernet in the backbone network with 3G and BWA.
Since 3G and BWA bring in high-speed data service capabilities with them; they are more Ip/ethernet-centric in nature. This requires the optical backbone to have flexible and high bandwidth capabilities to handle time-division multiplexed (TDM) and Ethernet traffic in an effective manner.
Vishant Vora, chief technology officer, Vodafone India said that IP over microwave is the present upgradation that the operators are investing in and network partners are promoting. Technologies over Ethernet and fiber are also prominent. Vodafone is trying to convert its existing 2G base stations to IP. Introduction of IP microwave radios is already done. Single RAN is one of the initiatives being considered actively.
“Empowering 2G/2.5G operators to take advantage of any infrastructure they presently have and leverage it to the fullest while evolving towards packet based transport is crucial in making not only 3G, but also advanced data services a success,” informs Yoav Valadarsky, associate vice president, solutions marketing, network solutions division, ECI Telecom.
Presently, microwave network being over IP; is definitely an upgradation but has its limitations. The existing FOADM based optical backbone networks have been very Tdm-centric so far. The challenges for the operators would be to build a high-capacity backbone network with capabilities of handling varying traffic mix of TDM and Ethernet traffic in an effective manner, especially in the metro environment.
“All Ethernet mobile backhaul can help operators achieve long-term opex savings while meeting the growing demand for data-hungry mobile services,” elaborates NSN spokesperson.
Currently, ROADM DWDM capabilities, universal switching fabric, Ethernet
switching capabilities, and OTN are some of key technologies that effectively address the challenges faced by the operators. Prasanjeet Khuntia, country manager, Tellabs India elaborates that ROADM based metro DWDM network is a critical piece of backbone for 3G and BWA. While some key 3G operators have started deployment of high-capacity optical backbone networks including ROADM based metro DWDM, others are in an advanced stage of evaluation.
“40G/100G WDM technology, RODAM technology, router cluster technology, Ethernet protection technology, or IP integration technology offer sustainable and scalable backbone network for the nextgeneration services,” says Ashwani Kumar, director, wireline, ZTE Telecom India.
The operators are slowly and gradually constructing high-speed backbone networks, utilizing many enhancements cre- ated to support carrier Ethernet over the past several years: 10GE/40GE/100GE, operations/administration/maintenance (OAM) services for connectivity and performance (IEEE 802.1ag, ITU Y.1731 in particular), synchronization via IEEE 1588, and many others. These technologies are here today.
S Sethumadhavan, director, marketing and strategy, Huawei India says, “The solutions for the next-generation networking will be built on the user-experience requirements that are driving an increased adoption towards cloud based networking.”
These new technologies benefiting 3G and BWA are focusing on backbone flexibility, seamless capacity growth, and support for packet based services. Innovative update to the GMPLS control plane is extending this automation from the optical layers upwards to advanced Ethernet/ packet and optical technologies.
A Promising Future
Introducing highly spectrum efficient radios, which could quickly provide the backhaul service when compared to connect fiber, holds the key for any successful vendor. “With introduction of the 4G services into the network, the IP based backhaul service will be the order of the day, which will eliminate major edge device such as router, switches, etc. Vendors, who have the expertise in providing IP based backhaul services coupled with edge devices, will act as the catalyst for the growth of broadband and 4G for the years to come,” comments Balaji Kulothungan, CEO, Pointred Telecom.
Today, Operators are focusing on two things; data download through dongles and secondly on social networking. If the backbone network is enhanced, they can open avenues of other relevant data services related to telemedicine, education, video conferencing, mobile, TV, etc, for which our country holds immense opportunity for growth. With coming of 4G in few years, the license holders like Augere, Tikona, and Bharti airtel should lay more emphasis on their backbone capacities before they launch their bouquet of fourth-generation services to avoid unnecessary network cramp.
Carriers don’t need major investments first and then wait for revenues, but rather they can match the expected revenues from 3G bandwidth rich applications with the capital they invest in infrastructure, that allows the services to be offered in the first place and grow this investment as the market grows. A win-win situation results, in which the subscribers enjoy not only 3G but also fourth-generation data services at affordable rates, while carriers increase their profits and improve their margins, despite the pressure of drastic revenue per bit reduction.