Colt's network transformation
Colt's technology and architecture specialist, Mirko Voltolini, talks to Gazettabyte about how the service provider has transformed its network from one based on custom platforms to an open, modular design.
It was obvious to Colt that something had to change. Its network architecture based on proprietary platforms running custom software was not sustainable; the highly customised network was cumbersome, resistant to change and expensive to run. The network also required a platform to be replaced - or at least a new platform added alongside an existing one - every five to seven years.
Mirko Voltolini
"The cost of this approach is enormous," says Mirko Voltolini, vice president technology and architecture at Colt Technology Services. "Not just in money but the time it takes to roll out a new platform."
Instead, the service provider has sought a modular approach to network design using standardised platforms that are separated from each other. That way, a new platform with a better feature set or improved economics can be slotted in without impacted the other platforms. Colt calls its resulting network a modular multi-service platform (MSP).
The MSP now delivers the majority of Colt's data networking and all-IP services. These includes Carrier Ethernet point-to-point, hub-and-spoke and private networks services, as well as internet access, IP VPNs and VoIP IP-based services.
The vendors chosen for the MSP include Cyan with its Z-Series packet-optical transport system (P-OTS) and Blue Planet software-defined networking (SDN) platform and Accedian Networks' customer premise equipment (CPE). Cyan's Z-Series does not support IP, so Colt uses Juniper Networks' and Alcatel-Lucent's IP edge platforms. Colt also has a legacy 20-year-old SDH network but despite using a P-OTS platform, it has decided to leave the SDH platform alone, with the modular MSP running alongside it.
Colt chose its vendors based on certain design goals. "The key was openness," says Voltolini. "We didn't want to have a closed system." It was Cyan's management system, the Blue Planet platform, that led Colt to choose Cyan.
Associated with Blue Planet is an ecosystem that allows the management software to control other vendors' platforms. Cyan uses 'element adapters' that mediate between its SDN interface software and the proprietary interfaces of its vendor partners. Cyan says that its Z-Series P-OTS appears as a third-party piece of equipment to its Blue Planet software in the same way as the other vendors' equipment are; a view confirmed by Colt. "Because of its openness, we have been able to integrate other vendors to use the same management system as if they were Cyan components," says Voltolini.
"Cyan was probably the best option available and we decided to go with it," says Voltolini. The company was looking at what was available two years ago and Voltolini points out that the market has evolved significantly since then. "In the end, if you want to move ahead, you need to make decisions," he says. "We are quite happy with what we have picked and we continue to improve it."
Colt says that as well as SDN, network functions virtualisation (NFV) is also important. "With the same modular platform we have created a virtual component which is a layer-3 CPE," says Voltolini. The company is issuing a request-for-information (RFI) regarding other CPE functions like firewalls, load-balancers and other networking components.
Benefits and lessons learned
Adopting the MSP has speeded up Colt's service delivery. Before the modular network, it would take between 30 and 45 days for Colt to fulfil a customer's request for a three-month-long Ethernet link upgrade, from 100 Megabit to 200 Megabit. Now, such a request can be fulfilled in seconds. "We didn't need any more layer-3 CPE and we can upgrade remotely the bandwidth," says Voltolini.
Colt also estimates that it will halve its operational costs once the new network is fully deployed; the network went live in November 2013 and has not been deployed in all locations. The operational expense improvement and the greater service flexibility both benefit Colt's bottom line, says Voltolini.
A key lesson learned from the network transformation is the importance of leading staff through change rather than any technological issues. "The technology has been a challenge but in the end, with the suppliers, you can design anything you want if you have the right level of collaboration," says Voltolini. "But when you completely transform the way you deliver services, you are touching everything that is part of the engine of the company."
Colt cites aspects such as engineering solutions, service delivery, service operations, systems and processes, and the sales process. "You need to lead the transition is such a way that everybody is going to follow you," says Voltolini.
Colt encountered obstacles created because of the staff's natural resistance to change. "Certain things took longer," says Voltolini. "We had to overcome obstacles that weren't really obstacles, just people's fear of change."
Telcos eye servers & software to meet networking needs
- The Network Functions Virtualisation (NFV) initiative aims to use common servers for networking functions
- The initiative promises to be industry disruptive
"The sheer massive [server] volumes is generating an innovation dynamic that is far beyond what we would expect to see in networking"
Don Clarke, NFV
Telcos want to embrace the rapid developments in IT to benefit their networks and operations.
The Network Functions Virtualisation (NFV) initiative, set up by the European Telecommunications Standards Institute (ETSI), has started work to use servers and virtualisation technology to replace the many specialist hardware boxes in their networks. Such boxes can be expensive to maintain, consume valuable floor space and power, and add to the operators' already complex operations support systems (OSS).
"Data centre technology has evolved to the point where the raw throughput of the compute resources is sufficient to do things in networking that previously could only be done with bespoke hardware and software," says Don Clarke, technical manager of the NFV industry specification group, and who is BT's head of network evolution innovation. "The data centre is commoditising server hardware, and enormous amounts of software innovation - in applications and operations - is being applied.”
"Everything above Layer 2 is in the compute domain and can be put on industry-standard servers"
The operators have been exploring independently how IT technology can be applied to networking. Now they have joined forces via the NFV initiative.
"The most exciting thing about the technology is piggybacking on the innovation that is going on in the data centre," says Clarke. "The sheer massive volumes is generating an innovation dynamic that is far beyond what we would expect to see in networking."
Another key advantage is that once networks become software-based, enormous amounts of flexibility results when creating new services, bringing them to market quickly while also reducing costs.
NFV and SDN
The NFV initiative is being promoted as a complement to software-defined networking (SDN).
The complementary relationship between NFV and SDN. Source: NFV.
SDN is focussed on control mechanisms to reconfigure networks that separate the control plane and the data plane. The transport network can be seen as dumb pipes with the control mechanisms adding the intelligence.
“There are other areas of the network where there is intrinsic complexity of processing rather than raw throughput,” says Clarke.
These include firewalls, session border controllers, deep packet inspection boxes and gateways - all functions that can be ported onto servers. Indeed, once running as software on servers such networking functions can be virtualised.
"Everything above Layer 2 is in the compute domain and can be put on industry-standard servers,” says Clarke. This could even include core IP routers but clearly that is not the best use of general-purpose computing, and the initial focus will be equipment at the edge of the network.
Clarke describes how operators will virtualise network elements and interface them to their existing OSS systems. “We see SDN as a longer journey for us,” he says. “In the meantime we want to get the benefits of network virtualisation alongside existing networks and reusing our OSS where we can.”
NFV will first be applied to appliances that lend themselves to virtualisation and where the impact on the OSS will be minimal. Here the appliance will be loaded as software on a common server instead of current bespoke systems situated at the network's end points. “You [as an operator] can start to draw a list of target things as to what will be of most interest,” says Clarke.
Virtualised network appliances are not a new concept and examples are already available on the market. Vanu's software-based radio access network technology is one such example. “What has changed is the compute resources available in servers is now sufficient, and the volume of servers [made] is so massive compared to five years ago,” says Clarke
The NFV forum aims to create an industry-wide understanding as to what the challenges are while ensuring that there are common tools for operators that will also increase the total available market.
Clarke stresses that the physical shape of operators' networks - such as local exchange numbers - will not change greatly with the uptake of NFV. “But the kind of equipment in those locations will change, and that equipment will be server-based," says Clarke.
"One of the things the software world has shown us is that if you sit on your hands, a player comes out of nowhere and takes your business"
One issue for operators is their telecom-specific requirements. Equipment is typically hardened and has strict reliability requirements. In turn, operators' central offices are not as well air conditioned as data centres. This may require innovation around reliability and resilience in software such that should a server fail, the system adapts and the server workload is moved elsewhere. The faulty server can then be replaced by an engineer on a scheduled service visit rather than an emergency one.
"Once you get into the software world, all kinds of interesting things that enhance resilience and reliability become possible," says Clarke.
Industry disruption
The NFV initiative could prove disruptive for many telecom vendors.
"This is potentially massively disruptive," says Clarke. "But what is so positive about this is that it is new." Moreover, this is a development that operators are flagging to vendors as something that they want.
Clarke admits that many vendors have existing product lines that they will want to protect. But these vendors have unique telecom networking expertise which no IT start-up entering the field can match.
"It is all about timing," says Clarke. "When do they [telecom vendors] decisively move their product portfolio to a software version is an internal battle that is happening right now. Yes, it is disruptive, but only if they sit on their hands and do nothing and their competitors move first."
Clarke is optimistic about to the vendors' response to the initiative. "One of the things the software world has shown us is that if you sit on your hands, a player comes out of nowhere and takes your business," he says.
Once operators deploy software-based network elements, they will be able to do new things with regard services. "Different kinds of service profiles, different kinds of capabilities and different billing arrangements become possible because it is software- not hardware-based."
Work status
The NFV initiative was unveiled late last year with the first meeting being held in January. The initiative includes operators such as AT&T, BT, Deutsche Telekom, Orange, Telecom Italia, Telefonica and Verizon as well as telecoms equipment vendors, IT vendors and technology providers.
One of the meeting's first tasks was to identify the issues to be addressed to enable the use of servers for telecom functions. Around 60 companies attended the meeting - including 20-odd operators - to create the organisational structure to address these issues.
Two experts groups - on security, and on performance and portability - were set up. “We see these issues as key for the four working groups,” says Clarke. These four working groups cover software architecture, infrastructure, reliability and resilience, and orchestration and management.
Work has started on the requirement specifications, with calls between the members taking place each day, says Clarke. The NFV work is expected to be completed by the end of 2014.
Further information:
White Paper: Network Functions Virtualisation: An Introduction, Benefits, Enablers, Challenges & Call for Action, click here