Part 2: Open networking
Edgecore Networks is expanding its open networking portfolio with cell-site gateways and passive optical networking (PON) platforms.
The company is backing two cell-site gateway designs that aggregate traffic from baseband units for 4G and 5G mobile networks. One design is from the Open Compute Project (OCP) that is available now and the second is from the Telecom Infra Project (TIP) that is planned for 2019 (see table).
Edgecore has also announced PON optical line terminal (OLT) platforms addressing 10-gigabit XGS-PON and GPON.
Source: ADVA, Edgecore Networks
Edgecore is a wholly-ownedsubsidiary of Accton Technology, a Taiwanese original design manufacturer (ODM) employing over 700 networking engineers that reported revenues exceeding $1.2 billion in 2017.
Open networking
Edgecore is a leading proponent of open networking that first data centre operators and now telecom operators are adopting.
Open networking refers to disaggregated designs where the hardware and software comes from separate companies. The hardware is a standardised white box developed in an open framework, while the accompanying software can be commercial code from a company or open-sourced.
Our focus is on all those attributes of open networking: disaggregation, the hardware and software design of standard platforms, and making those designs open
Telecom networks have traditionally been built using proprietary equipment from systems vendors that includes the complete software stack. But the leading telcos have moved away from this approach to avoid being locked into a systems vendor's roadmap. Instead, they are active in open frameworks and are embracing disaggregated open designs, having seen the benefits achieved by the internet content providers that pioneered the approach.
“The IT industry for years have been buying servers and purposing them for whatever application they are designated for, adding an operating system and application software on top,” says Mark Basham, vice president business development and marketing, EMEA at Edgecore. “Now we are seeing the telecom industry shift to that model; they see where the value should be.”
White-box platforms built using merchant silicon promise to reduce the number of specialised platforms in an operator’s network, reducing costs by simplifying platform qualification and support.
“Our focus is on all those attributes of open networking: disaggregation, the hardware and software design of standard platforms, and making those designs open,” says Bill Burger, vice president, business development and marketing for North America at Edgecore.
OCP, TIP and ONF
Edgecore is active in three leading open framework initiatives whose memberships include large-scale data centre operators, telcos, equipment makers, systems integrators, software partners and chip players.
Edgecore is a member of OCP that was founded to address the data centre but now plays an important role in telecoms. The company is also part of TIP that was established in 2016 and includes internet giants Facebook and Microsoft as well as leading telecom operators, systems vendors, components players and others. Edgecore is also a key white-box partner as part of the Open Networking Foundation’s (ONF) reference-design initiative.
Edgecore Networks' involvement in the ONF's reference design projects. Diagram first published in July 2018. Source: ONF.
Cell-site gateways
Edgecore has announced the availability of its AS7316-26XB, the industry’s first open cell-site gateway white-box design from the OCP that originated as an AT&T specification.
The company is also active in TIP’s cell-site gateway initiative. Edgecore will make and market the Odyssey Disaggregated Cell Site Gateway (Odyssey-DCSG) design that is backed by TIP’s operator members Telefonica, Orange, TIM Brazil and Vodafone. BT is also believed to be backing the TIP gateway.
The gateway aggregates the radio baseband unit (BBU) at a cell site back into the transport network.
The OCP cell-site gateway has a more advanced specification compared to the Odyssey. The AS7316-26XB uses a more powerful Intel processor and employs a 300-gigabit Broadcom Qumran-AX switch chip that aggregates the baseband traffic for transmission into the network.
The platform’s client-side interfaces include 16 SFP+ ports that supports either 1 Gigabit Ethernet (GbE) SFP or 10GbE SFP+ pluggable modules, eight 25GbE ports that accommodate either 10GbE SFP+ or 25GbE SFP28 modules, and two 100GbE QSFP28 uplinks. Some of the 25GbE ports could be used to expand the uplink capacity, if needed.
In contrast, the TIP Odyssey-DCSG platform uses a 120-gigabit Qumran switch chip while its interfaces include provide four 1GbE RJ45 ports and eight 10GbE or 25GbE SFP28 ports. Accordingly, the platform’s uplinks are at 25GbE.
“They [the OCP and TIP gateways] are very different boxes in terms of their performance,” says Basham.
Current deployed mobile platforms don't have sufficient capacity to support LTE Advanced Pro, never mind 5G, says Basham: “All the operators are looking at what is the right time to insert these boxes in the network.”
Telcos need to decide how much they are willing to spend up front. They could deploy a larger capacity but costlier cell-site gateway to future-proof their mobile backhaul for up to a decade. Or they could install the smaller-capacity Odyssey-DCSG that will suffice for five years before requiring an upgrade.
Given that the largest operators will deploy the gateways in units of hundreds of thousands, the capital expenditure outlay will be significant.
Basham says there will be a family of cell-site gateways and points out that the TIP specification originally had three ‘service configurations’. The latest TIP specification document now has a fourth service configuration that differs significantly from the other three in its port count and capabilities. “It shows that there is no one-size-fits-all,” says Basham.
The company also has announced two open disaggregated PON products, part of the OCP.
The ASXvOLT16 is a 10-gigabit OLT platform that supports XGS-PON and NG-PON2. The open OLT platform uses Broadcom’s 800-gigabit Qumran-MX switch chip and its BCM68620 Maple OLT device.
The platform’s interfaces includes 16 XFP ports supporting 10-gigabit optics while for the uplink traffic, four 100GbE ports are used. Each 10-gigabit interface will support 32 or 64 PON optical network units (ONU) typically.
“To support NG-PON2 will require the virtual OLT hardware abstraction layer to be adapted slightly, and also firmware to be put on the Broadcom chips,” says Basham. “The big difference between XGS-PON and NG-PON2 is in the plug-in optics.” More costly tunable optics will be required for NG-PON2. The 1 rack unit (1RU) PON OLT design is available now.
Edgecore has also contributed GPON OLT designs that conform with Deutsche Telecom’s Open GPON OLT design. The Edgecore ASGvOLT32 and ASGvOLT64 GPON OLTs support 32- and 64-GPON ports, respectively, while there are two 100GbE and eight 25GbE uplink ports.
The two GPON OLTs will sample in the first quarter of 2019, moving to volume production one quarter later.
We are at the cusp of bringing together all the parts to make Cassini a deployable solution
Cassini
Edgecore is also bringing its Cassini packet-optical transport white-box platform to market.
Like TIP’s Voyager box, Cassini uses the Broadcom StrataXGS Tomahawk 3.2-terabit switch chip. But while the Voyager comes with built-in coherent interfaces based on Acacia’s AC-400 module, Cassini is a modular design that has eight card slots. Each slot can accommodate one of three module options: a coherent CFP2-ACO, a coherent CFP2-DCO or two QSFP28 100-gigabit pluggables. The Cassini platform also has 16 fixed QSFP28 ports.
Accordingly, the 1.5RU Cassini box can be configured using only the coherent interfaces required. The box could be set up as a 3.2-terabit switch using QSFP28 modules only or as a transport box with up to 1.6 terabits of client-side interfaces and 1.6 terabits of line-side coherent interfaces. This contrasts with the 1RU Voyager that offers 2 terabits of switch capacity with its dozen 100-gigabit client-side interfaces and 800 gigabits of coherent line-side capacity.
“We are at the cusp of bringing together all the parts to make Cassini a deployable solution,” says Basham. “The focus is to get it deployed in the market.”
Edgecore sees Cassini as a baseline for future products. One obvious direction is to increase the platform’s capacity using Broadcom’s 12.8-terabit Tomahawk 3 switch chip. Edgecore already offers a Tomahawk 3-based switch for the data centre.
Such a higher-capacity Cassini platform would support 400GbE client-side interfaces and 400- or 800-gigabit coherent line-side interfaces. “We think that there is a future need for such a platform but we are not actively developing it right now,” says Burger.
A second direction for Cassini’s development is as a platform suited to routeing using larger look-up tables and deep buffering. Such a platform would use merchant silicon such as Broadcom’s Jericho chip. “We think there is a need for that as service providers deploy packet transport platforms in their networks,” says Burger.
Business model
The Cassini platform arose as part of Edgecore’s detailed technology planning discussions with its leading internet content provider customers.
“We recognised a need for more modularity in an open-packet transponder, the ability to mix-and-match the number of packet switching interfaces with the coherent optical interfaces,” says Burger.
Edgecore then approached TIP before contributing the Cassini platform to the organisation’s Open Optical and Packet Transport group.
When Edgecore contributes a design to an open framework such as the OCP or TIP, the design undergoes a review resulting in valuable feedback from member companies.
“We end up making modifications to improve the design in some cases and it then goes through an approval process,” says Burger. “After that, we contribute the design package and its available to anyone without any royalty obligation.”
At first glance, it is not obvious how contributing a platform design that other firms can build benefits Edgecore. But Burger says Edgecore benefits is several ways.
The organisation members’ feedback improves the product’s design. Edgecore also raises industry awareness of its platforms including among the OCP’s and TIP’s large service provider members.
Making the design available to members also offers the operators a potential second source for Edcore’s white box designs, strengthening confidence and their appeal.
And once a design is open sourced, software partners including start-ups will investigate the design as a platform for their code which can result in partnerships. “This benefits us and benefits the software companies,” says Burger.
Edgecore stresses that open-networking platforms are going to take time before they become widely adopted across service providers’ networks.
“It is going to be an evolution, starting with high-volume, more standardised use cases,” concludes Burger.
Part 1: TIP white-box designs, click here