Cisco's P-OTS: Denser and distributed

Cisco Systems’ carrier packet transport (CPT) product family adds metro packet optical transport to its existing switch and router offerings.

Cisco claims the CPT is its second-generation packet optical transport system (P-OTS), complementing the ONS 15454. But some analysts view the CPT as the vendor’s first true packet optical transport product.

"This announcement is an acknowledgement that P-OTS equipment is important and that operators are insisting on it"

Sterling Perrin, Heavy Reading

The CPT family comprises the CPT 200 and CPT 600 platforms, while the CPT 50 port extension shelf enables the CPT products to be implemented as a distributed switch architecture.

Gazettabyte spoke to Stephen Liu, manager, service provider marketing at Cisco Systems about the announcement and asked three analysts on the significance of Cisco’s CPT, how the product family advances packet optical transport and how the platforms will benefit operators.

 Carrier packet transport family

The CPT platforms are aimed at operators transitioning their metro networks from traditional SONET/SDH to packet-based transport.

Cisco says the CPT is its second-generation P-OTS. A first generation P-OTS supports dense wavelength division multiplexing (DWDM) with some Ethernet capability. “The truly integrated P-OTS that unites the simplicity of optical delivery with packet routing is in the second generation,” says Cisco’s Liu.

Market research firm, Heavy Reading, defines P-OTS as a platform that combines SONET/SDH, connection-oriented Ethernet, DWDM and, depending on where the platform is used within the network, also optical transport network (OTN) switching and reconfigurable optical add-drop multiplexers (ROADMs). The global P-OTS market will total $870 million in 2010, says Heavy Reading.

The CPT combines DWDM, OTN, Ethernet, multi-protocol label switching – transport profile (MPLS-TP) and ROADMs. MPLS-TP is a stripped down version of the multi-protocol label switching (MPLS) protocol and is used for point-to-point communication. MPLS-TP’s ability to interoperate with IP-MPLS allows operators to combine packet-based technology with transport control in the access and aggregation part of the network, says Cisco.

So what is new with the introduction of the CPT platforms? “The ability to do high-density packet optical transport with MPLS-TP,” says Liu.  

Cisco has fitted 160 Gigabit-per-second (Gbps) switching capacity into the two-rack-sized CPT 200 platform and 480Gbps in the six-rack CPT 600. The respective platform port counts are 176 Gigabit Ethernet (GbE) and 352 GbE ports, says Liu.

Cisco also stresses the functionality integrated into the dense platforms. “We have ROADMs coming together with transponders that do the electrical-to-optical conversion, and the TDM/Ethernet switching functions,” says Liu. “It takes about 30 inches of ROADM/transponder and TDM/Ethernet switching functions on separate platforms; with the CPT it is condensed into 10.5 inches of rack space.”

The result, says Liu, is a 60% operational expense (OpEx) saving in power consumption, cooling and space.  Cisco also claims that unifying the management of the optical and packet transport domains will result in a 20% OpEx saving.

The CPT 50 satellite shelf complements the CPT platforms. The CPT 50 has 44 GbE ports and four 10GbE uplink ports. “The shelf can be deployed locally next to a CPT platform or up to 80km away, but from a management point-of-view it all looks like a single box,” says Liu.

The platforms do not support 40 or 100Gbps interfaces but that is part of the product roadmap, says Liu. Earlier this year, Cisco acquired 40 and 100 Gigabit transport specialist, CoreOptics. Nor will the platform family be limited to the metro. “Long-haul opportunities are certainly open to us,” says Liu.

Cisco says that the CPT platforms are being trialled and will be available from 1Q of 2011.  Several large operators including Verizon, XO Communications and BT are in various stages of platform evaluation.

Analysts’ comments

Sterling Perrin, senior analyst at Heavy Reading 

We believe the CPT is Cisco’s most significant optical announcement since its acquisition spree at the beginning of the decade.

Cisco has always positioned its legacy product, the ONS 15454, as packet transport but really it is a multi-service provision platform (MSPP) – or as Cisco calls it, a multi-service transport platform (MSTP) ­– with SONET/SDH and DWDM. We have not counted that as a P-OTS. What it is doing now is entering the [P-OTS] market.

Cisco is an IP router and Ethernet switch company and is strong on IP-over-DWDM.  It has pushed that story to operators for years and while that has been happening, there has been the packet optical transport trend which has been gaining steam. Vendors have either used P-OTS for next-generation networks or have had a dual strategy of switches and routers and P-OTS. Cisco have always been in the switch-router space. This announcement is an acknowledgement that P-OTS equipment is important and that operators are insisting on it.

Cisco will be competitive with the CPT based on its newness. The density looks impressive – 480Gbps for the six-rack and 160Gbps for the two-rack platform. But this is a generational thing; in time as everyone else releases their next product, they will also have a dense platform. But for now it is a differentiator. The remote shelf is also interesting but it is unclear to what degree that will be telling with operators.

As for the operators mentioned in the Cisco press release, Verizon has already picked Fujitsu and Tellabs as the P-OTS suppliers for its metro and regional networks. The big opportunity with Verizon is in the core, and the first two CPT platforms are not for core.

Mention of BT is also interesting as the operator is in favour of the opposite approach, based on switches and routers from Alcatel-Lucent and Juniper, and has moved away from P-OTS. XO is probably the most likely operator [of the three mentioned] to adopt the platform and already uses Cisco’s ONS 15454. 

The opportunity for Cisco is protecting the ONS 15454 customer base that is looking to move from MSPPs to packet optical transport.

Heavy Reading believes the standalone DWDM and MSPP markets are declining, but will remain large markets for the next two years. Accordingly, it makes sense for Cisco to continue supporting the legacy product line.

Eve Griliches, managing partner, ACG Research

The CPT is more along the lines of a purpose built P-OTS than some variations that have came to market.  It has all the requirements a P-OTS should have including a hybrid switch fabric that supports packet and OTN.  I suspect the packet functionality is very good, and possibly better than other transport carriers have delivered, but the operators are still testing and they will speak soon.  I do know that operators I've spoken with are already very impressed with what they’ve seen.

"Operators I've spoken with are already very impressed with what they’ve seen"

Eve Griliches, ACG Research

In terms of how the CPT will benefit operators, the CPT is a metro aggregation P-OTS box, and it will have to compete with Tellabs and Fujitsu who have been shipping equipment for the metro for two years.  But Cisco will likely bring better packet functionality, which is what operators have been waiting for.

Rick Talbot, senior analyst, transport and routing infrastructure, Current Analysis

Cisco is introducing a product into a space recently defined by other vendors – packet-based access/ aggregation devices for backhaul, currently mobile backhaul.  Example devices are the Alcatel-Lucent 1850 TSS-100, ECI Telecom’s BG-64 and the Ericsson OMS 1410.

"The CPT will likely blur the line between metro P-OTS and packet-based access/ aggregation devices"

Rick Talbot, Current Analysis

CPT brings quite a significant advantage in port density and packet-switching capacity. The CPT 200’s 160Gbps capacity is twice that of the OMS 1410, the current leader in that category.  The CPT 600 boasts the capacity of a full metro P-OTS in a chassis the size of a small MSPP. From Cisco’s perspective, the CPT product line is not about introducing a new access/ aggregation device but extending the metro architecture closer to cell towers and end-users.

The CPT will likely blur the line between metro P-OTS and packet-based access/ aggregation devices.  It has a modest size and power consumption. It also extends MPLS, in the form of MPLS-TP, to the very edge of the operator’s network, enabling a single end-to-end packet-forwarding method.

The high capacity and low-power consumption of the CPT will, of course, save operators OpEx and CapEx.  In addition, the platform extends a single connection-oriented management view to the end-user site, minimising management expense.

The flexibility of the platform will further benefit the operator if and when the operator deploys cache content storage at the network edge. But such deployment of servers beyond the central office remains to be seen.

Related links:

See also Intune Networks' packet optical transport platform